Chapter 18 Infectious Diseases infecting the Skin and Eyes

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Acne Propionibacterium acnes Endogenous

Lipase inflammatory

mediator other enzymes

Based on clinical picture na Antibiotics(topical

or oral) isotretinoin na

Impetigo

Staphylococcus aureus

Direct Contact indirect contact

Exfoliative toxin A coagulase

other enzymes

Routinely based on clinical signs when necessary

culture and Gram stain

coagulase and catalase tests

multitest systems PCR

Hygiene practices

Topical Mupirocin oral cephalexin

Seen more often in older children

adults

Streptococcus pyrogenes ldquo

Streptokinase plasminogen-

binding ability hyaluronidase M

protein

ldquo ldquo ldquo

Seen more often in newborns may

have some involvement in all

impetigo (preceding S aureus in

staphylococcal impetigo)

Cellulitis

S aureus

Parenteral implantation

ldquoldquo

Same with impetigo S

aureus

Based on clinical signs na

Oral or IV antibiotic (caphalexin)

surgery sometimes necessary

na

Streptococcus pyrogenes

Same with impetigo S pyrogenes

ldquona ldquo na

Other bacteria or fungi na ldquo na

Aggressive treatment with (see

Cellulitis trs)

More common in immunocompressed

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Scalded Skin Syndrome S aureus Direct contact

droplet contactExfoliative toxins

A and B

Histological sections culture performed but

false (-) common because toxins

alone are sufficient for

disease

Eliminate carriers in contact with

neonates

Immediate systemic

antibiotics (cloxacillin or cephalexin)

Split in skin occurs within

epidermis

Gas gangreneClostridium

perfringens other species

Vehicle (soil) endogenous

transfer from skin GI tract

reproductive tract

Alpha toxin other exotoxins

enzymes gas formation

Gram stain CT scans (abdominal infections) X ray

clinical picture

Clean wounds debride dead

tissue

Penicillin amp Clindamycin

surcgical removal oxygen therapy

na

Chickenpox

Human herpesvirus 3

(varicella- zoster virus)

Droplet contact inhalation of

aerosolized lesion fluid

Ability to fuse cells ability to

remain latent in ganglia

Based largely on clinical

appearance

Live attenuated vaccine vaccine

to prevent reactivation of

latent virus (shingles)

None in uncomplicated cases acyclovir

for high risk

No fever prodrome lesions are superficial in

centripetal distribution (more

in center of the body)

Smallpox Variola virus Droplet contact indirect contact

Ability to dampen avoid immune

responseldquo Live virus vaccine

(vaccinia virus) na

Fever precedes rash lesions are

deep and in centrifugal distribution

Measles (Rubeola) Measles virus Droplet contactSyncytium

formationability to suppress CMI

ELISA for IgM acute

convalescent IgG

Live attenuated vaccine (MMR)

No antivirals Vit A antibiotics for

secondary bacterial infections

Starts on head spreads to whole body lasts over a

week

Rubella Rubella virus ldquo

In fetuses inhibition of

mitosisapoptosis and damage to

vascular endothelium

Acute IgM acute convalescent IgG ldquo na

Milder red rash lasts

approximately 3 days

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Fifth Disease Parvovirus B19 Droplet contact direct contact na Usually diagnosed

clinically na na

ldquoSlapped- facerdquo rash first spreads

to limbs and trunk tends to be confluent rather

than distinct bumps

Roseola Human herpesvirus 6 or 7 Ability to remain

latent ldquo na na

High fever precedes rash

stagemdashrash not always present

ldquoStreptococcus

pyrogenes (lysogenized)

Droplet contact direct contact Erythrogenic toxin

Examination of skin lesions

throat culture (beta- hemolytic on blood agar

sensitive to bacitracin rapid antigen tests)

Hygiene practicesPenicillin

cephalexin in penicillin- allergic

Sandpaper feel to affected ski

severe sore throat

Warts Human papillomaviruses

Direct contact autoinoculation indirect contact

naClinical diagnosis

also histology microscopy PCR

Avoid contactHome treatment cryosurgery (virus

not eliminated)na

Molluscum contagiosum

Molluscum contagiosum

viruses

Direct contact including sexual

contact autoinoculation

na ldquo ldquo

Usually none but mechanical

removal can be performed

na

Leishmaniasis Leishmania spp Biological vector Multiplication with macrophages

Culture of protozoa

microscopic visualization

Avoiding sand fly Sodium stibogluconate

Mucocutaneous and systemic

forms

Cutaneous Anthrax Bacillus anthracis Direct contact

with endospores

Endospore formation

capsule lethal amp edema factor

Culture on blood agar serology

PCR performed by CDC

Avoid contact vaccine available

but not widely used

Ciprofloxacin doxycycline levofloxacin

Can be fatal

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Cutaneous Infections

Trichophyton Microsporum

Epidermophyton

Direct and indirect contact

vehicle (soil)

Ability to degrade keratin invoke hypersensitivity

Microscopic examination KOH staining

culture

Avoid contact

Topical tolnaftate

itraconazole terbinafine miconazole

thiabendazine

na

Superficial Infections (Tinea

versicolor)Malassezia furfur Endogenous

ldquonormal biotardquo na Usually clinical KOH can be used na Topical

antifungals na

Neonatal conjunctivitis

Chlamydia trachomatis or

Neisseria gonorrhoea

Vertical na Gram stain and culture

Screen mothers apply antibiotic or silver nitrate

to newborn eyes

Topical and oral antibiotics

In babies lt 28 days old

Bacterial conjunctivitis

S pyrogenes S pneumonia

Staphylococcus aureus

Haemophilus

Direct indirect contact

na Clinical diagnosis Hygiene Broad- spectrum topical antibiotic

often ciprofloxacin

Mucopurulent discharge

influenza Moraxella and

also N gonorrhea C trachomatis

Viral conjunctivitis

Adenoviruses and others ldquo na ldquo ldquo

None although antibiotics often given because

type of infection not distinguished

Serous (clear) discharge

Trachoma C trachomatis serovars A- C

Indirect contact mechanical

vector

Intracellular growth

Detection of inclusion bodies

in stained preparations

Hygiene vector control prompt

treatment of initial infection

Azithromycin or topical

erythromycinna

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Keratitis Herpes simplex virus

Reactivation of latent virus

although primary infections can

occur in the eye

Latency

Usually clinical diagnosis viral culture or PCR if

needed

naTopical

trifluridine andor oral acyclovir

na

Miscellaneous microorganisms

Often traumatic introduction (parenteral)

Various Various na Specific antimicrobials na

River blindnessWolbachia plus

Onchocerca volvulus

Biological vectorInduction of

inflammatory response

ldquoSkin snipsrdquo small piece of

skin in NaCl solrsquon examined under microscope and

microfilariae counted

Avoiding black fly Ivermectin Worms often visible in eye

Summing Up

Microorganism DiseaseGram positive bacteria Acne

Impetigo cellulitis scalded skin syndromeImpetigo cellulitisGas gangreneCutaneous anthrax

Gram negative bacteria Neonatal conjunctivitisNeonatal conjunctivitis trachomaRiver blindness

DNA Viruses Chickenpox smallpox fifth disease roseola warts molluscum contagiosum keratitis

RNA Viruses Measles rubellaFungi Ringworm superficial mycosisProtozoa LeishmaniasisHelminths River blindness

Chapter 19 Infectious Diseases Affecting the Nervous System

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

FeaturesMeningitis

Neisseria meningitidis Droplet contact

Capsule endotoxin IgA

protease

Gram stain culture of CSF

blood rapid antigenic tests

Conjugated vaccine

rifampin or tetracycline

used to protect contacts

Penicillin G orCefotaxime

Petechiae meningo- coccemia

Streptococcus pneumoniae Droplet contact

Capsule induction of apoptosis

hemolysin and hydrogen peroxide

production

Gram stain culture of CSF

Two vaccines Prevnar

(children) and Pneumovax

(adults)

Cefotaxime check for

resistance (add vancomycin in

that case)

Serious acute most common meningitis in

adults

Haemophilus influenzae Droplet contact Capsule

Culture on chocolate agar Hib vaccine Cefotaxime

Serious acute less common since

vaccine became available

Listeria monocytogenes Vehicle (food) Intracellular

growth

Cold enrichment

rapid methods

Cooking food avoiding

unpasteurized dairy products

Ampicillin trimethoprim- sulfamethox-

azole

Asymptomatic in healthy adults

meningitisin neonates elderly

and immuno- compromised

Cryptococcus neoformans

Vehicle (air dust soil)

Capsule melanin

production

Negative staining

biochemical tests DNA

probes

naAmphotericin B and fluconazole

Acute or chronic most common in AIDS

patients

Coccidioides immitis

Vehicle (air dust soil)

Granuloma (spherule) formation

Identification of spherules

cultivation on Sabouraudrsquos

agar

Avoiding airborne spores

Amphotericin B or oral or IV itraconazole

Almost exlusively in endemic regions

Viruses Droplet contact Lytic infection Initially absence na Usually none Generally milder than

of host cells

of bacteriafungi

protozoa followed by viral

culture or antigen tests

unless specific virus identified

and specific antiviral exists)

bacterial or fungal

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Neonatal Meningitis

Streptococcus agalactiae Vertical (during

birth) Capsule

Culture motherrsquos genital tract on blood agar CSF

culture of neonate

Culture and treatment of

mother

Penicillin G plus aminoglycosides

Most common positive culture of mother confirms

diagnosis

Escherichia coli strain K1 Vertical (during

birth) ndash CSF Gram stainculture ndash Cefotaxime plus

aminoglycosideSuspected if infant is

premature

Listeria monocytogenes Vertical Intracellular

growth

Cold enrichment

rapid methods

Cooking food avoiding

unpasteurized dairy products

Ampicillin trimethoprim-

sulfamethoxazole

Suspected if infant is premature

Meningo-encephalitis

Primary Amoebic Meningoencephaliti

sNaegleria fowleri

Vehicle (exposure while

swimming in water)

InvasivenessExamination of

CSF brain imaging

Avoid warm fresh water

Amphotericin B mostly

ineffective

Granulomatous Amoebic

Meningoencephalitis

Acanthamoeba

Direct contact InvasivenessExamination of

CSF brain imaging

ndash

Surgical excision of granulomas Ketoconazole

may help

Meningitis Arboviruses (viruses causing WEE EEE

California encephalitis SLE

West Nile encephalitis)

Vector (arthropod

bites)

Attachment fusion invasion

capabilities

History rapid serological tests

Insect control vaccines for WEE and EEE

available

None History of exposure to insect important

Herpes simplex 1 or 2

Vertical or reactivation of latent infection

ndash

Clinical presentation PCR Ab tests growth of virus in cell culture

Maternal screening for

HSVAcyclovir

In infants disseminated disease present rare between

30 and 50 years

JC virus Ubiquitous ndashPCR of

cerebrospinal fluid

None Zidovudine or other antivirals

In severely immunocompromised

especially AIDSImmunologic

reaction to other viral infections

Sequelae of measles other viral infections

and occasionally

ndash History of viral infection or vaccination

ndash Steroids anti-inflammatory

agents

History of virusvaccine

exposure critical

vaccination

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing Features

Subacute Encephalitis

Toxoplasma gondii Vehicle (meat) or fecal-oral

Intracellular growth

Serological detection of IgM

Personal hygiene food

hygiene

Pyrimethamine andor

sulfadiazine

Subacute slower development of disease

Subacute sclerosing panencephalitis

Persistence of measles virus

Cell fusion evasion of immune system

EEGs None None History of measles

Prions

CJD= directparenteral

contact with infected tissue

or inherited vCJD= vehicle

(meat parenteral)

Avoidance of host immune

responseBiopsy Avoiding tissue None Long incubation period fast

progression once it begins

Rabies Rabies virusParenteral (bite trauma) droplet

contact

Envelope glycoprotein

RT-PCR of saliva Ab detection of serum or CSF

skin biopsy

HDCVmdashinactivated

vaccine

Postexposure passive and

active immunization

na

Poliomyelitis Poliovirus Fecal-oral vehicle

Attachment mechanisms

Viral culture serology

Live attenuated (developing

world) or inactivated

vaccine (developed

world)

None palliative supportive

Tetanus Clostridium tetani Parenteral direct contact

Tetanospasm exotoxin Symptomatic Tetanus toxoid

immunization

Combination of passive antitoxin

and tetanus toxoid active

immunization supportive

na

Botulism Clostridium botulinum

Vehicle (food-borne toxin

airborne organism) direct contact (wound)

parenteral (injection)

Botulinum exotoxin

Culture of organism

demonstration of toxin

Food hygiene toxoid

immunization available for laboratory

professionals

Antitoxin supportive care na

African Sleeping Sickness

Trypanosoma brucei subspecies

gambiense or rhodesiense

Vector verticalImmune

evasion by antigen shifting

Microscopic examination of

blood CSFVector control

Suramin or pentamidine

(early) melarsoprol

(late)

Chapter 20 Infectious Diseases Affecting the Cardiovascular and lymphatic systems

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Acute Endocarditis

Staphylococcus aureus Parenteral Attachment Blood culture Aseptic surgery

injections

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Acute onset high fatality rate

Subacute Endocarditis

Alpha-hemolytic streptococci

Endogenous transfer of

normal biota to bloodstream

Attachment Blood culture

Prophylactic antibiotics before

invasive procedures

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Slower onset

Septicemia Bacteria or fungiParenteral

endogenous transfer

Cell wall or membrane

componentsBlood culture -

Broad-spectrum antibiotic until

identification and susceptibilities

tested

Plague Yersinia pestis

Vector biological also droplet contact

(pneumonic) and direct contact

with body fluids

Capsule Yop system

plasminogen activator

Culture or Gram stain of blood or bubo aspirate

Flea and or animal control

vaccine available for high-risk individuals

Streptomycin or gentamicin

Tularemia Francisella tularensis

Vector biological also direct contact

with body fluids from infected

animal airborne

Intracellular growth

Culture dangerous to lab workers and not reliable serology most often used

Live attenuated vaccine for high-risk individuals

Gentamicin or streptomycin

Lyme Disease Borrelia burgdorferi Vector biological Antigenic shifting adhesins

ELISA for Ab PCR Tick avoidance

Doxycycline andor amoxicillin (3ndash4

weeks) also cephalosporins and

penicillin

Infectious Mononucleosis

Epstein-Barr virus (EBV)

Direct indirect contact

parenteral

Latency ability to incorporate into

host DNA

Differential blood count Monospot

test for heterophile antibody

specific ELISA

ndash Supportive Most common in teens

Cytomegalovirus (CMV)

Direct indirect contact

parenteral vertical

Latency ability to fuse cells

Virus isolation and growth ELISA or PCR

tests

Vaccine in trials

Only for immunosuppressed

patients not usually for

mononucleosis

More common in adults dangerous to

fetus

Hemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Yellow fever Yellow fever virus Biological vector Disruption of clotting factors ELISA PCR Live attenuated

vaccine available Supportive Accompanied by jaundice

Dengue Fever Dengue fever virus Biological vector Disruption of clotting factors Rise in IgM titers

Live attenuated vaccine being

testedSupportive

ldquoBreakbone feverrdquomdashso named due to

severe pain

Ebola andor Marburg

Ebola virus Marburg virus

Direct contact body fluids

Disruption of clotting factors

PCR viral culture (conducted at

CDC)ndash Supportive

Massive hemorrhage rash

sometimes present

Lassa Fever Lassa fever virus

Droplet contact (aerosolized

rodent excretions)

direct contact with infected

fluids

Disruption of clotting factors ELISA Avoiding rats

safe food storage RibavirinChest pain

deafness as long-term sequelae

Nonhemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Brucellosis Brucella abortus or B suis

Direct contact airborne

parenteral (needlesticks)

Intracellular growth

avoidance of destruction by

phagocytes

Gram stain of biopsy material

Animal control pasteurization of

milk

Doxycycline plus (gentamicin or streptomycin)

Undulating fever muscle aches

Q fever Coxiella burnetii Airborne direct contact

Endosporelike structure

Serological tests for antibody

Vaccine for high-risk population Doxycycline

Airborne route of transmission

variable disease presentation

Cat-Scratch Disease Bartonella henselae food-borne Endotoxin

Biopsy of lymph nodes plus Gram staining ELISA (performed by

CDC)

Clean wound sites Azithromycin

History of cat bite or scratch fever not

always present

Trench Fever Bartonella quintana Parenteral (cat scratch or bite) Endotoxin

ELISA (performed by

CDC)Avoid lice Doxycycline or

erythromycin

Endocarditis common 5-day

fever

Ehrlichioses Ehrlichia species Biological vector (lice) - PCR indirect

antibody test Avoid lice Doxycycline Seasonal occurrence (AprilndashOct)

Rocky Mountain

Spotted FeverRickettsia rickettsii Biological vector

(tick)

Induces apoptosis in cells

lining blood vessels

Fluorescent antibody PCR Avoid lice Doxycycline

Most common in east and southeast

United States

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

MalariaPlasmodium

falciparum P vivax P ovale P malariae

Biological vector (mosquito)

vertical

Multiple life stages multiple antigenic types

ability to scavenge

glucose GPI cytoadherence

Blood smear serological methods

Mosquito control use of bed nets no vaccine yet

available prophylactic antiprotozoal

agents

Chloroquine mefloquine artemisinin

Fansidar quinine or proguanil

Anthrax Bacillus anthracis

Vehicle (air soil) indirect contact (animal hides) vehicle (food)

Triple exotoxin capsule

Culture direct fluorescent

antibody tests

Vaccine for high-risk population postexposure

antibiotic prophylaxis

Doxycycline ciprofloxacin

penicillin

HIV Infection and AIDS

Human immunodeficiency

virus 1 or 2

Direct contact (sexual)

parenteral (blood-borne)

vertical (perinatal and via breast

milk)

Attachment syncytia

formation reverse

transcriptase high mutation

rate

Initial screening for antibody followed by

Western blot confirmation of

antibody

Avoidance of contact with infected sex

partner contaminated blood breast

milk

HAART (reverse transcriptase inhibitors plus

protease inhibitors) Fuzeon nonnucleoside RT

inhibitors

Adult T-Cell Leukemia HTLV-I

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Hairy-Cell Leukemia (Possibly) HTLV-II

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Chapter 21 Infectious disease affecting the respiratory system

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Rhinitis Approximately 200 viruses

Indirect contact droplet contact

Attachment proteins most

symptoms induced by host

response

Not necessary Hygiene practices For symptoms only

Sinusitis Various bacteria often mixed

infection

Endogenous (opportunism)

Culture not usually

performed diagnosis based

Broad-spectrum antibiotics

Much more common than fungal

on clinical presentation occasionally X rays or other

imaging technique used

Various fungi

Introduction by trauma or

opportunisticOvergrowrth

Same

Physical removal of fungus in severe cases antifungals

used

Suspect in immunocompromised

patients

Otitis Media

Streptococcus pneumoniae

Endogenous (may follow

upper respiratory tract infection by S pneumoniae or

other microorganisms)

Capsule hemolysin

Usually relies on clinical

symptoms and failure to resolve within 72 hours

Pneumococcal conjugate vaccine

(heptavalent)

Wait for resolution if needed

amoxicillin (are high rates of resistance) or amoxicillin 1113106

clavalanate or cefuroxine

ndash

Haemophilus influenzae

Endogenous (follows upper

respiratory tract infection)

Capsule fimbriae Same Hib vaccine Same as for S pneumoniae ndash

Other bacteria Endogenous ndash Same None

Wait for resolution if needed a broad-spectrum antibiotic

(azithromycin) might be used in

absence of etiologic diagnosis

Suspect if fully vaccinated against

other two

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Pharyngitis

Streptococcus pyogenes

Droplet or direct contact

LTA M protein hyaluronic acid

capsule SLS and SLO

superantigens

Beta-hemolytic on blood agar sensitive to bacitracin rapid

antigen tests

Hygiene practices

Penicillin cephalexin in

penicillin-allergic

Generally more severe than viral

pharyngitis

Viruses All forms of contact ndash

Goal is to rule out S pyogenes further diagnosis usually

not performed

Hygiene practices

Symptom relief only

Hoarseness frequently

accompanies viral pharyngitis

Diphtheria Corynebacterium diphtheriae

Droplet contact direct contact or indirect contact

with contaminated

Exotoxin diphtheria toxin

Tellurite mediummdashgrayblack colonies

club-shaped morphology on

Gram stain

Diphtheria toxoid vaccine (part of

DTaP)

Antitoxin plus penicillin or

erythromycin

fomitestreatment begun before definitive

identification

Pertussis (Whooping

Cough)

Bordetella pertussis Droplet contact

FHA (adhesion) pertussis toxin and tracheal

cytotoxin endotoxin

Grown on B-G charcoal or potato-

glycerol agar diagnosis can be

made on symptoms

Acellular vaccine (DTaP)

erythromycin or trimethoprim-

sulfamethoxazole for contacts

Mainly supportive erythromycin to

decrease communicability

RSV DiseaseRespiratory

syncytial virus (RSV)

Droplet and indirect contact

Syncytia formation

Direct antigen testing

Passive antibody in high-risk

children

Ribavirin in severe cases

Influenza Influenza A B and C viruses

Droplet contact direct contact some indirect

contact

Glycoprotein spikes overall

ability to change genetically

Viral culture (3ndash10 days) or rapid

antigen-based or PCR tests

Killed injected vaccine or inhaled live attenuated

vaccinemdashtaken annually

Amantadine rimantadine zanamivir or oseltamivir

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Tuberculosis

Mycobacterium tuberculosis

Vehicle (airborne)

Lipids in wall ability to

stimulate strong cell-mediated

immunity (CMI)

Rapid methods plus culture initial tests are skin testing and

chest X ray

Avoiding airborne M

tuberculosis BCG vaccine in other countries

Isoniazid rifampin and pyrazinamide 1113106 ethambutol or streptomycin for

varying lengths of time (always lengthy) if

resistant two other drugs added

to regimen

Responsible for nearly all TB except

for HIV

Mycobacterium avium complex

Vehicle (airborne) ndash Positive blood

culture

Rifabutin or azithromycin given to AIDS

patients at risk

Azithromycin or clarithromycin plus

one additional antibiotic

Suspect this in HIV-positive patients

PneumoniaStreptococcus pneumoniae

Droplet contact or endogenous

transferCapsule

Gram stain often diagnostic alpha-

hemolytic on blood agar

Pneumococcal polysaccharide

vaccine (23-valent)

Cefotaxime ceftriaxone ketek much resistance

Patient usually severely ill

Legionella species Vehicle (water droplets) ndash

Requires selective charcoal yeast extract agar

serology unreliable

ndashFluoroquinolone

azithromycin clarithromycin

Mild pneumonias in healthy people can be severe in elderly

or immunocompromised

Mycoplasma pneumoniae

Droplet contact Adhesins Rule out other etiologic agents

No vaccine no permanent immunity

Recommended not to treat in most

cases doxycycline or macrolides may

be used if

Usually mild ldquowalking pneumoniardquo

necessary

Hantavirus

Vehiclemdashairborne virus emitted from

rodents

Ability to induce inflammatory

response

Serology (IgM) PCR identification of antigen in tissue

Avoid mouse habitats and

droppingsSupportive Rapid onset high

mortality rate

SARS-associated coronavirus

Droplet direct contact

Rule out other agents serology

PCRndash Supportive Rapid onset

Histoplasma capsulatum

Vehiclemdashinhalation of

contaminated soil

Survival in phagocytes

Usually serological (rising Ab titers)

Avoid contaminated soil bat bird

droppings

Amphotericin B andor itraconazole

Many infections asymptomatic

Pneumocystis jiroveci Droplet contact ndash Immunofluorescence

Antibiotics given to AIDS patients to prevent this

Trimethoprim- sulfamethoxazole

Vast majority occur in AIDS patients

Nosocomial Pneumonia

Gram-negative and gram-positive

bacteria from upper respiratory tract or stomach

Endogenous (aspiration) Culture of lung fluids

Elevating patientrsquos head preoperative

education care of respiratory

equipment

Broad-spectrum antibiotics

Chapter 22 Infectious diseases affecting the GIT

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Dental CariesStreptococcus mutans Streptococcus sobrinus

othersDirect contact Adhesion acid

production -Oral hygiene

fluoride supplementation

Removal of diseased tooth

material

Periodontitis

Polymicrobial community including

some or all of Tannerella forsythus

Actinobacillus actinomycetemcomitans

Porphyromonas gingivalis others

Induction of inflammation Oral hygiene

Removal of plaque and calculus gum

reconstruction tetracycline

Necrotizing Ulcerative

Gingivitis and Periodontitis

Polymicrobial community (Treponema

vincentii Prevotella intermedia

Fusobacterium species)

Inflammation Oral hygiene

Debridement of damaged tissue metronidazole

clindamycin

Mumps Mumps virus (genus Paramyxovirus) Droplet contact

Spike-induced syncytium formation

Clinical fluorescent Ag tests ELISA for

Ab

MMR live attenuated

vaccineSupportive

Gastritis and Helicobacter pylori Adhesions ELISA None Antibiotics plus

Gastric Ulcers urease endoscopy

acid suppressors (clarithromycin or

metronidazole plus omeprazole

or bismuth subsalicylate)

DiseaseAcute

Diarrhea

Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

Features

Bacterial Causes

SalmonellaVehicle (food

beverage) fecal-oral

Adhesins endotoxin

Stool culture not

usually necessary

Food hygiene and

personal hygiene

Rehydration no antibiotic

for uncomplicated

disease

Usually Sometimes

Often associated

with chickens reptiles

Shigella Fecal-oral

Endotoxin enterotoxin

shiga toxins in some strains

Stool culture antigen

testing for shiga toxin

Food hygiene and

personal hygiene

TMP-SMZ rehydration Often Often Very low

ID50

Shiga-toxin- producing E coli O157H7 (EHEC)

Vehicle (food beverage) fecal-

oral

Shiga toxins proteins for attachment secretion

effacement

Stool culture antigen

testing for shiga toxin

Avoid live E coli (cook meat and

clean vegetables)

Antibiotics contraindicated supportive

measures

Often UsuallyHemolytic

uremic syndrome

Other E coli (non-shiga-toxin- producing)

Vehicle fecal-oral

Various proteins for attachment secretion

effacement heat-labile

andor heat- stable

exotoxins invasiveness

Stool culture not usually

necessary in absence of blood fever

Food and personal hygiene

Rehydration Sometimes SometimesEIEC ETEC EPEC

Campylobacter Vehicle (food water) fecal-oral

Adhesins exotoxin

induction of autoimmunity

Stool culture not usually necessary dark-field

microscopy

Food and personal hygiene

Rehydration erythromycin

in severe cases

(antibiotic resistance

rising)

Usually NoGuillain-

Barreacute syndrome

Yersinia Vehicle (food Intracellular Cold- Food and None in most Usually Occasionall Severe

water) fecal-oral indirect contact growth enrichment

stool culturepersonal hygiene

cases doxycycline or TMP-SMZ for bacteremia

y abdominal pain

Clostridium difficile

Endogenous (normal biota)

Enterotoxins A and B

Stool culture PCR

ELISA demonstration of toxins

in stool

ndash

Withdrawal of antibiotic in severe cases

metronidazole or vancomycin

SometimesNot

usually mucus

Antibiotic- associated diarrhea

Vibrio choleraeVehicle (water

and some foods) fecal-oral

Cholera toxin (CT)

Clinical diagnosis

microscopic techniques serological detection of

antitoxin

Water hygiene

Rehydration in severe

cases tetracycline

TMP-SMZ

No prominent Rice-water stools

Non-bacterial causes

Cryptosporidium Vehicle (water food) fecal-oral

Intracellular growth

Acid-fast staining ruling out bacteria

Water treatment proper food

handling

None paromomycin

used sometimes

Often Not usually

Resistant to chlorine disinfectio

n

Rotavirus Fecal-oral vehicle fomite ndash Usually not

performedOral live

virus vaccine Rehydration Often No Severe in babies

Other Viruses Fecal-oral vehicle - Usually not performed Hygiene Rehydration Sometimes No

Acute Diarrhea

with Vomiting

(Food Poisoning)

Staphylococcus aureus exotoxin

Vehicle (food)

Heat-stable exotoxin

Usually based on

epidemiological evidence

Proper food handling None Not Usually No

Suspect in foods with high salt or

sugar content

Bacillus cereusHeat-stable toxin heat-labile toxin

Microscopic analysis of

food or stool

Two forms emetic and diarrheal

Clostridium perfringens

Heat-labile toxin

Detection of toxin in stool

Acute abdominal

pain

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

FeaturesChronic Diarrhea Enteroaggregativ

e E coli (EAEC)Vehicle (food

water) fecal-oral

Difficult to distinguish

from other E coli

None or ciprofloxacin No

Sometimes mucus

also

Chronic in the

malnourished

Cyclospora cayetanensis

Fecal-oral vehicle Invasiveness Stool examination

PCR

Washing cooking

food personal hygiene

TMP-SMZ Usually No ndash

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

Gas gangreneClostridium

perfringens other species

Vehicle (soil) endogenous

transfer from skin GI tract

reproductive tract

Alpha toxin other exotoxins

enzymes gas formation

Gram stain CT scans (abdominal infections) X ray

clinical picture

Clean wounds debride dead

tissue

Penicillin amp Clindamycin

surcgical removal oxygen therapy

na

Chickenpox

Human herpesvirus 3

(varicella- zoster virus)

Droplet contact inhalation of

aerosolized lesion fluid

Ability to fuse cells ability to

remain latent in ganglia

Based largely on clinical

appearance

Live attenuated vaccine vaccine

to prevent reactivation of

latent virus (shingles)

None in uncomplicated cases acyclovir

for high risk

No fever prodrome lesions are superficial in

centripetal distribution (more

in center of the body)

Smallpox Variola virus Droplet contact indirect contact

Ability to dampen avoid immune

responseldquo Live virus vaccine

(vaccinia virus) na

Fever precedes rash lesions are

deep and in centrifugal distribution

Measles (Rubeola) Measles virus Droplet contactSyncytium

formationability to suppress CMI

ELISA for IgM acute

convalescent IgG

Live attenuated vaccine (MMR)

No antivirals Vit A antibiotics for

secondary bacterial infections

Starts on head spreads to whole body lasts over a

week

Rubella Rubella virus ldquo

In fetuses inhibition of

mitosisapoptosis and damage to

vascular endothelium

Acute IgM acute convalescent IgG ldquo na

Milder red rash lasts

approximately 3 days

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Fifth Disease Parvovirus B19 Droplet contact direct contact na Usually diagnosed

clinically na na

ldquoSlapped- facerdquo rash first spreads

to limbs and trunk tends to be confluent rather

than distinct bumps

Roseola Human herpesvirus 6 or 7 Ability to remain

latent ldquo na na

High fever precedes rash

stagemdashrash not always present

ldquoStreptococcus

pyrogenes (lysogenized)

Droplet contact direct contact Erythrogenic toxin

Examination of skin lesions

throat culture (beta- hemolytic on blood agar

sensitive to bacitracin rapid antigen tests)

Hygiene practicesPenicillin

cephalexin in penicillin- allergic

Sandpaper feel to affected ski

severe sore throat

Warts Human papillomaviruses

Direct contact autoinoculation indirect contact

naClinical diagnosis

also histology microscopy PCR

Avoid contactHome treatment cryosurgery (virus

not eliminated)na

Molluscum contagiosum

Molluscum contagiosum

viruses

Direct contact including sexual

contact autoinoculation

na ldquo ldquo

Usually none but mechanical

removal can be performed

na

Leishmaniasis Leishmania spp Biological vector Multiplication with macrophages

Culture of protozoa

microscopic visualization

Avoiding sand fly Sodium stibogluconate

Mucocutaneous and systemic

forms

Cutaneous Anthrax Bacillus anthracis Direct contact

with endospores

Endospore formation

capsule lethal amp edema factor

Culture on blood agar serology

PCR performed by CDC

Avoid contact vaccine available

but not widely used

Ciprofloxacin doxycycline levofloxacin

Can be fatal

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Cutaneous Infections

Trichophyton Microsporum

Epidermophyton

Direct and indirect contact

vehicle (soil)

Ability to degrade keratin invoke hypersensitivity

Microscopic examination KOH staining

culture

Avoid contact

Topical tolnaftate

itraconazole terbinafine miconazole

thiabendazine

na

Superficial Infections (Tinea

versicolor)Malassezia furfur Endogenous

ldquonormal biotardquo na Usually clinical KOH can be used na Topical

antifungals na

Neonatal conjunctivitis

Chlamydia trachomatis or

Neisseria gonorrhoea

Vertical na Gram stain and culture

Screen mothers apply antibiotic or silver nitrate

to newborn eyes

Topical and oral antibiotics

In babies lt 28 days old

Bacterial conjunctivitis

S pyrogenes S pneumonia

Staphylococcus aureus

Haemophilus

Direct indirect contact

na Clinical diagnosis Hygiene Broad- spectrum topical antibiotic

often ciprofloxacin

Mucopurulent discharge

influenza Moraxella and

also N gonorrhea C trachomatis

Viral conjunctivitis

Adenoviruses and others ldquo na ldquo ldquo

None although antibiotics often given because

type of infection not distinguished

Serous (clear) discharge

Trachoma C trachomatis serovars A- C

Indirect contact mechanical

vector

Intracellular growth

Detection of inclusion bodies

in stained preparations

Hygiene vector control prompt

treatment of initial infection

Azithromycin or topical

erythromycinna

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Keratitis Herpes simplex virus

Reactivation of latent virus

although primary infections can

occur in the eye

Latency

Usually clinical diagnosis viral culture or PCR if

needed

naTopical

trifluridine andor oral acyclovir

na

Miscellaneous microorganisms

Often traumatic introduction (parenteral)

Various Various na Specific antimicrobials na

River blindnessWolbachia plus

Onchocerca volvulus

Biological vectorInduction of

inflammatory response

ldquoSkin snipsrdquo small piece of

skin in NaCl solrsquon examined under microscope and

microfilariae counted

Avoiding black fly Ivermectin Worms often visible in eye

Summing Up

Microorganism DiseaseGram positive bacteria Acne

Impetigo cellulitis scalded skin syndromeImpetigo cellulitisGas gangreneCutaneous anthrax

Gram negative bacteria Neonatal conjunctivitisNeonatal conjunctivitis trachomaRiver blindness

DNA Viruses Chickenpox smallpox fifth disease roseola warts molluscum contagiosum keratitis

RNA Viruses Measles rubellaFungi Ringworm superficial mycosisProtozoa LeishmaniasisHelminths River blindness

Chapter 19 Infectious Diseases Affecting the Nervous System

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

FeaturesMeningitis

Neisseria meningitidis Droplet contact

Capsule endotoxin IgA

protease

Gram stain culture of CSF

blood rapid antigenic tests

Conjugated vaccine

rifampin or tetracycline

used to protect contacts

Penicillin G orCefotaxime

Petechiae meningo- coccemia

Streptococcus pneumoniae Droplet contact

Capsule induction of apoptosis

hemolysin and hydrogen peroxide

production

Gram stain culture of CSF

Two vaccines Prevnar

(children) and Pneumovax

(adults)

Cefotaxime check for

resistance (add vancomycin in

that case)

Serious acute most common meningitis in

adults

Haemophilus influenzae Droplet contact Capsule

Culture on chocolate agar Hib vaccine Cefotaxime

Serious acute less common since

vaccine became available

Listeria monocytogenes Vehicle (food) Intracellular

growth

Cold enrichment

rapid methods

Cooking food avoiding

unpasteurized dairy products

Ampicillin trimethoprim- sulfamethox-

azole

Asymptomatic in healthy adults

meningitisin neonates elderly

and immuno- compromised

Cryptococcus neoformans

Vehicle (air dust soil)

Capsule melanin

production

Negative staining

biochemical tests DNA

probes

naAmphotericin B and fluconazole

Acute or chronic most common in AIDS

patients

Coccidioides immitis

Vehicle (air dust soil)

Granuloma (spherule) formation

Identification of spherules

cultivation on Sabouraudrsquos

agar

Avoiding airborne spores

Amphotericin B or oral or IV itraconazole

Almost exlusively in endemic regions

Viruses Droplet contact Lytic infection Initially absence na Usually none Generally milder than

of host cells

of bacteriafungi

protozoa followed by viral

culture or antigen tests

unless specific virus identified

and specific antiviral exists)

bacterial or fungal

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Neonatal Meningitis

Streptococcus agalactiae Vertical (during

birth) Capsule

Culture motherrsquos genital tract on blood agar CSF

culture of neonate

Culture and treatment of

mother

Penicillin G plus aminoglycosides

Most common positive culture of mother confirms

diagnosis

Escherichia coli strain K1 Vertical (during

birth) ndash CSF Gram stainculture ndash Cefotaxime plus

aminoglycosideSuspected if infant is

premature

Listeria monocytogenes Vertical Intracellular

growth

Cold enrichment

rapid methods

Cooking food avoiding

unpasteurized dairy products

Ampicillin trimethoprim-

sulfamethoxazole

Suspected if infant is premature

Meningo-encephalitis

Primary Amoebic Meningoencephaliti

sNaegleria fowleri

Vehicle (exposure while

swimming in water)

InvasivenessExamination of

CSF brain imaging

Avoid warm fresh water

Amphotericin B mostly

ineffective

Granulomatous Amoebic

Meningoencephalitis

Acanthamoeba

Direct contact InvasivenessExamination of

CSF brain imaging

ndash

Surgical excision of granulomas Ketoconazole

may help

Meningitis Arboviruses (viruses causing WEE EEE

California encephalitis SLE

West Nile encephalitis)

Vector (arthropod

bites)

Attachment fusion invasion

capabilities

History rapid serological tests

Insect control vaccines for WEE and EEE

available

None History of exposure to insect important

Herpes simplex 1 or 2

Vertical or reactivation of latent infection

ndash

Clinical presentation PCR Ab tests growth of virus in cell culture

Maternal screening for

HSVAcyclovir

In infants disseminated disease present rare between

30 and 50 years

JC virus Ubiquitous ndashPCR of

cerebrospinal fluid

None Zidovudine or other antivirals

In severely immunocompromised

especially AIDSImmunologic

reaction to other viral infections

Sequelae of measles other viral infections

and occasionally

ndash History of viral infection or vaccination

ndash Steroids anti-inflammatory

agents

History of virusvaccine

exposure critical

vaccination

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing Features

Subacute Encephalitis

Toxoplasma gondii Vehicle (meat) or fecal-oral

Intracellular growth

Serological detection of IgM

Personal hygiene food

hygiene

Pyrimethamine andor

sulfadiazine

Subacute slower development of disease

Subacute sclerosing panencephalitis

Persistence of measles virus

Cell fusion evasion of immune system

EEGs None None History of measles

Prions

CJD= directparenteral

contact with infected tissue

or inherited vCJD= vehicle

(meat parenteral)

Avoidance of host immune

responseBiopsy Avoiding tissue None Long incubation period fast

progression once it begins

Rabies Rabies virusParenteral (bite trauma) droplet

contact

Envelope glycoprotein

RT-PCR of saliva Ab detection of serum or CSF

skin biopsy

HDCVmdashinactivated

vaccine

Postexposure passive and

active immunization

na

Poliomyelitis Poliovirus Fecal-oral vehicle

Attachment mechanisms

Viral culture serology

Live attenuated (developing

world) or inactivated

vaccine (developed

world)

None palliative supportive

Tetanus Clostridium tetani Parenteral direct contact

Tetanospasm exotoxin Symptomatic Tetanus toxoid

immunization

Combination of passive antitoxin

and tetanus toxoid active

immunization supportive

na

Botulism Clostridium botulinum

Vehicle (food-borne toxin

airborne organism) direct contact (wound)

parenteral (injection)

Botulinum exotoxin

Culture of organism

demonstration of toxin

Food hygiene toxoid

immunization available for laboratory

professionals

Antitoxin supportive care na

African Sleeping Sickness

Trypanosoma brucei subspecies

gambiense or rhodesiense

Vector verticalImmune

evasion by antigen shifting

Microscopic examination of

blood CSFVector control

Suramin or pentamidine

(early) melarsoprol

(late)

Chapter 20 Infectious Diseases Affecting the Cardiovascular and lymphatic systems

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Acute Endocarditis

Staphylococcus aureus Parenteral Attachment Blood culture Aseptic surgery

injections

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Acute onset high fatality rate

Subacute Endocarditis

Alpha-hemolytic streptococci

Endogenous transfer of

normal biota to bloodstream

Attachment Blood culture

Prophylactic antibiotics before

invasive procedures

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Slower onset

Septicemia Bacteria or fungiParenteral

endogenous transfer

Cell wall or membrane

componentsBlood culture -

Broad-spectrum antibiotic until

identification and susceptibilities

tested

Plague Yersinia pestis

Vector biological also droplet contact

(pneumonic) and direct contact

with body fluids

Capsule Yop system

plasminogen activator

Culture or Gram stain of blood or bubo aspirate

Flea and or animal control

vaccine available for high-risk individuals

Streptomycin or gentamicin

Tularemia Francisella tularensis

Vector biological also direct contact

with body fluids from infected

animal airborne

Intracellular growth

Culture dangerous to lab workers and not reliable serology most often used

Live attenuated vaccine for high-risk individuals

Gentamicin or streptomycin

Lyme Disease Borrelia burgdorferi Vector biological Antigenic shifting adhesins

ELISA for Ab PCR Tick avoidance

Doxycycline andor amoxicillin (3ndash4

weeks) also cephalosporins and

penicillin

Infectious Mononucleosis

Epstein-Barr virus (EBV)

Direct indirect contact

parenteral

Latency ability to incorporate into

host DNA

Differential blood count Monospot

test for heterophile antibody

specific ELISA

ndash Supportive Most common in teens

Cytomegalovirus (CMV)

Direct indirect contact

parenteral vertical

Latency ability to fuse cells

Virus isolation and growth ELISA or PCR

tests

Vaccine in trials

Only for immunosuppressed

patients not usually for

mononucleosis

More common in adults dangerous to

fetus

Hemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Yellow fever Yellow fever virus Biological vector Disruption of clotting factors ELISA PCR Live attenuated

vaccine available Supportive Accompanied by jaundice

Dengue Fever Dengue fever virus Biological vector Disruption of clotting factors Rise in IgM titers

Live attenuated vaccine being

testedSupportive

ldquoBreakbone feverrdquomdashso named due to

severe pain

Ebola andor Marburg

Ebola virus Marburg virus

Direct contact body fluids

Disruption of clotting factors

PCR viral culture (conducted at

CDC)ndash Supportive

Massive hemorrhage rash

sometimes present

Lassa Fever Lassa fever virus

Droplet contact (aerosolized

rodent excretions)

direct contact with infected

fluids

Disruption of clotting factors ELISA Avoiding rats

safe food storage RibavirinChest pain

deafness as long-term sequelae

Nonhemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Brucellosis Brucella abortus or B suis

Direct contact airborne

parenteral (needlesticks)

Intracellular growth

avoidance of destruction by

phagocytes

Gram stain of biopsy material

Animal control pasteurization of

milk

Doxycycline plus (gentamicin or streptomycin)

Undulating fever muscle aches

Q fever Coxiella burnetii Airborne direct contact

Endosporelike structure

Serological tests for antibody

Vaccine for high-risk population Doxycycline

Airborne route of transmission

variable disease presentation

Cat-Scratch Disease Bartonella henselae food-borne Endotoxin

Biopsy of lymph nodes plus Gram staining ELISA (performed by

CDC)

Clean wound sites Azithromycin

History of cat bite or scratch fever not

always present

Trench Fever Bartonella quintana Parenteral (cat scratch or bite) Endotoxin

ELISA (performed by

CDC)Avoid lice Doxycycline or

erythromycin

Endocarditis common 5-day

fever

Ehrlichioses Ehrlichia species Biological vector (lice) - PCR indirect

antibody test Avoid lice Doxycycline Seasonal occurrence (AprilndashOct)

Rocky Mountain

Spotted FeverRickettsia rickettsii Biological vector

(tick)

Induces apoptosis in cells

lining blood vessels

Fluorescent antibody PCR Avoid lice Doxycycline

Most common in east and southeast

United States

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

MalariaPlasmodium

falciparum P vivax P ovale P malariae

Biological vector (mosquito)

vertical

Multiple life stages multiple antigenic types

ability to scavenge

glucose GPI cytoadherence

Blood smear serological methods

Mosquito control use of bed nets no vaccine yet

available prophylactic antiprotozoal

agents

Chloroquine mefloquine artemisinin

Fansidar quinine or proguanil

Anthrax Bacillus anthracis

Vehicle (air soil) indirect contact (animal hides) vehicle (food)

Triple exotoxin capsule

Culture direct fluorescent

antibody tests

Vaccine for high-risk population postexposure

antibiotic prophylaxis

Doxycycline ciprofloxacin

penicillin

HIV Infection and AIDS

Human immunodeficiency

virus 1 or 2

Direct contact (sexual)

parenteral (blood-borne)

vertical (perinatal and via breast

milk)

Attachment syncytia

formation reverse

transcriptase high mutation

rate

Initial screening for antibody followed by

Western blot confirmation of

antibody

Avoidance of contact with infected sex

partner contaminated blood breast

milk

HAART (reverse transcriptase inhibitors plus

protease inhibitors) Fuzeon nonnucleoside RT

inhibitors

Adult T-Cell Leukemia HTLV-I

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Hairy-Cell Leukemia (Possibly) HTLV-II

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Chapter 21 Infectious disease affecting the respiratory system

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Rhinitis Approximately 200 viruses

Indirect contact droplet contact

Attachment proteins most

symptoms induced by host

response

Not necessary Hygiene practices For symptoms only

Sinusitis Various bacteria often mixed

infection

Endogenous (opportunism)

Culture not usually

performed diagnosis based

Broad-spectrum antibiotics

Much more common than fungal

on clinical presentation occasionally X rays or other

imaging technique used

Various fungi

Introduction by trauma or

opportunisticOvergrowrth

Same

Physical removal of fungus in severe cases antifungals

used

Suspect in immunocompromised

patients

Otitis Media

Streptococcus pneumoniae

Endogenous (may follow

upper respiratory tract infection by S pneumoniae or

other microorganisms)

Capsule hemolysin

Usually relies on clinical

symptoms and failure to resolve within 72 hours

Pneumococcal conjugate vaccine

(heptavalent)

Wait for resolution if needed

amoxicillin (are high rates of resistance) or amoxicillin 1113106

clavalanate or cefuroxine

ndash

Haemophilus influenzae

Endogenous (follows upper

respiratory tract infection)

Capsule fimbriae Same Hib vaccine Same as for S pneumoniae ndash

Other bacteria Endogenous ndash Same None

Wait for resolution if needed a broad-spectrum antibiotic

(azithromycin) might be used in

absence of etiologic diagnosis

Suspect if fully vaccinated against

other two

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Pharyngitis

Streptococcus pyogenes

Droplet or direct contact

LTA M protein hyaluronic acid

capsule SLS and SLO

superantigens

Beta-hemolytic on blood agar sensitive to bacitracin rapid

antigen tests

Hygiene practices

Penicillin cephalexin in

penicillin-allergic

Generally more severe than viral

pharyngitis

Viruses All forms of contact ndash

Goal is to rule out S pyogenes further diagnosis usually

not performed

Hygiene practices

Symptom relief only

Hoarseness frequently

accompanies viral pharyngitis

Diphtheria Corynebacterium diphtheriae

Droplet contact direct contact or indirect contact

with contaminated

Exotoxin diphtheria toxin

Tellurite mediummdashgrayblack colonies

club-shaped morphology on

Gram stain

Diphtheria toxoid vaccine (part of

DTaP)

Antitoxin plus penicillin or

erythromycin

fomitestreatment begun before definitive

identification

Pertussis (Whooping

Cough)

Bordetella pertussis Droplet contact

FHA (adhesion) pertussis toxin and tracheal

cytotoxin endotoxin

Grown on B-G charcoal or potato-

glycerol agar diagnosis can be

made on symptoms

Acellular vaccine (DTaP)

erythromycin or trimethoprim-

sulfamethoxazole for contacts

Mainly supportive erythromycin to

decrease communicability

RSV DiseaseRespiratory

syncytial virus (RSV)

Droplet and indirect contact

Syncytia formation

Direct antigen testing

Passive antibody in high-risk

children

Ribavirin in severe cases

Influenza Influenza A B and C viruses

Droplet contact direct contact some indirect

contact

Glycoprotein spikes overall

ability to change genetically

Viral culture (3ndash10 days) or rapid

antigen-based or PCR tests

Killed injected vaccine or inhaled live attenuated

vaccinemdashtaken annually

Amantadine rimantadine zanamivir or oseltamivir

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Tuberculosis

Mycobacterium tuberculosis

Vehicle (airborne)

Lipids in wall ability to

stimulate strong cell-mediated

immunity (CMI)

Rapid methods plus culture initial tests are skin testing and

chest X ray

Avoiding airborne M

tuberculosis BCG vaccine in other countries

Isoniazid rifampin and pyrazinamide 1113106 ethambutol or streptomycin for

varying lengths of time (always lengthy) if

resistant two other drugs added

to regimen

Responsible for nearly all TB except

for HIV

Mycobacterium avium complex

Vehicle (airborne) ndash Positive blood

culture

Rifabutin or azithromycin given to AIDS

patients at risk

Azithromycin or clarithromycin plus

one additional antibiotic

Suspect this in HIV-positive patients

PneumoniaStreptococcus pneumoniae

Droplet contact or endogenous

transferCapsule

Gram stain often diagnostic alpha-

hemolytic on blood agar

Pneumococcal polysaccharide

vaccine (23-valent)

Cefotaxime ceftriaxone ketek much resistance

Patient usually severely ill

Legionella species Vehicle (water droplets) ndash

Requires selective charcoal yeast extract agar

serology unreliable

ndashFluoroquinolone

azithromycin clarithromycin

Mild pneumonias in healthy people can be severe in elderly

or immunocompromised

Mycoplasma pneumoniae

Droplet contact Adhesins Rule out other etiologic agents

No vaccine no permanent immunity

Recommended not to treat in most

cases doxycycline or macrolides may

be used if

Usually mild ldquowalking pneumoniardquo

necessary

Hantavirus

Vehiclemdashairborne virus emitted from

rodents

Ability to induce inflammatory

response

Serology (IgM) PCR identification of antigen in tissue

Avoid mouse habitats and

droppingsSupportive Rapid onset high

mortality rate

SARS-associated coronavirus

Droplet direct contact

Rule out other agents serology

PCRndash Supportive Rapid onset

Histoplasma capsulatum

Vehiclemdashinhalation of

contaminated soil

Survival in phagocytes

Usually serological (rising Ab titers)

Avoid contaminated soil bat bird

droppings

Amphotericin B andor itraconazole

Many infections asymptomatic

Pneumocystis jiroveci Droplet contact ndash Immunofluorescence

Antibiotics given to AIDS patients to prevent this

Trimethoprim- sulfamethoxazole

Vast majority occur in AIDS patients

Nosocomial Pneumonia

Gram-negative and gram-positive

bacteria from upper respiratory tract or stomach

Endogenous (aspiration) Culture of lung fluids

Elevating patientrsquos head preoperative

education care of respiratory

equipment

Broad-spectrum antibiotics

Chapter 22 Infectious diseases affecting the GIT

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Dental CariesStreptococcus mutans Streptococcus sobrinus

othersDirect contact Adhesion acid

production -Oral hygiene

fluoride supplementation

Removal of diseased tooth

material

Periodontitis

Polymicrobial community including

some or all of Tannerella forsythus

Actinobacillus actinomycetemcomitans

Porphyromonas gingivalis others

Induction of inflammation Oral hygiene

Removal of plaque and calculus gum

reconstruction tetracycline

Necrotizing Ulcerative

Gingivitis and Periodontitis

Polymicrobial community (Treponema

vincentii Prevotella intermedia

Fusobacterium species)

Inflammation Oral hygiene

Debridement of damaged tissue metronidazole

clindamycin

Mumps Mumps virus (genus Paramyxovirus) Droplet contact

Spike-induced syncytium formation

Clinical fluorescent Ag tests ELISA for

Ab

MMR live attenuated

vaccineSupportive

Gastritis and Helicobacter pylori Adhesions ELISA None Antibiotics plus

Gastric Ulcers urease endoscopy

acid suppressors (clarithromycin or

metronidazole plus omeprazole

or bismuth subsalicylate)

DiseaseAcute

Diarrhea

Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

Features

Bacterial Causes

SalmonellaVehicle (food

beverage) fecal-oral

Adhesins endotoxin

Stool culture not

usually necessary

Food hygiene and

personal hygiene

Rehydration no antibiotic

for uncomplicated

disease

Usually Sometimes

Often associated

with chickens reptiles

Shigella Fecal-oral

Endotoxin enterotoxin

shiga toxins in some strains

Stool culture antigen

testing for shiga toxin

Food hygiene and

personal hygiene

TMP-SMZ rehydration Often Often Very low

ID50

Shiga-toxin- producing E coli O157H7 (EHEC)

Vehicle (food beverage) fecal-

oral

Shiga toxins proteins for attachment secretion

effacement

Stool culture antigen

testing for shiga toxin

Avoid live E coli (cook meat and

clean vegetables)

Antibiotics contraindicated supportive

measures

Often UsuallyHemolytic

uremic syndrome

Other E coli (non-shiga-toxin- producing)

Vehicle fecal-oral

Various proteins for attachment secretion

effacement heat-labile

andor heat- stable

exotoxins invasiveness

Stool culture not usually

necessary in absence of blood fever

Food and personal hygiene

Rehydration Sometimes SometimesEIEC ETEC EPEC

Campylobacter Vehicle (food water) fecal-oral

Adhesins exotoxin

induction of autoimmunity

Stool culture not usually necessary dark-field

microscopy

Food and personal hygiene

Rehydration erythromycin

in severe cases

(antibiotic resistance

rising)

Usually NoGuillain-

Barreacute syndrome

Yersinia Vehicle (food Intracellular Cold- Food and None in most Usually Occasionall Severe

water) fecal-oral indirect contact growth enrichment

stool culturepersonal hygiene

cases doxycycline or TMP-SMZ for bacteremia

y abdominal pain

Clostridium difficile

Endogenous (normal biota)

Enterotoxins A and B

Stool culture PCR

ELISA demonstration of toxins

in stool

ndash

Withdrawal of antibiotic in severe cases

metronidazole or vancomycin

SometimesNot

usually mucus

Antibiotic- associated diarrhea

Vibrio choleraeVehicle (water

and some foods) fecal-oral

Cholera toxin (CT)

Clinical diagnosis

microscopic techniques serological detection of

antitoxin

Water hygiene

Rehydration in severe

cases tetracycline

TMP-SMZ

No prominent Rice-water stools

Non-bacterial causes

Cryptosporidium Vehicle (water food) fecal-oral

Intracellular growth

Acid-fast staining ruling out bacteria

Water treatment proper food

handling

None paromomycin

used sometimes

Often Not usually

Resistant to chlorine disinfectio

n

Rotavirus Fecal-oral vehicle fomite ndash Usually not

performedOral live

virus vaccine Rehydration Often No Severe in babies

Other Viruses Fecal-oral vehicle - Usually not performed Hygiene Rehydration Sometimes No

Acute Diarrhea

with Vomiting

(Food Poisoning)

Staphylococcus aureus exotoxin

Vehicle (food)

Heat-stable exotoxin

Usually based on

epidemiological evidence

Proper food handling None Not Usually No

Suspect in foods with high salt or

sugar content

Bacillus cereusHeat-stable toxin heat-labile toxin

Microscopic analysis of

food or stool

Two forms emetic and diarrheal

Clostridium perfringens

Heat-labile toxin

Detection of toxin in stool

Acute abdominal

pain

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

FeaturesChronic Diarrhea Enteroaggregativ

e E coli (EAEC)Vehicle (food

water) fecal-oral

Difficult to distinguish

from other E coli

None or ciprofloxacin No

Sometimes mucus

also

Chronic in the

malnourished

Cyclospora cayetanensis

Fecal-oral vehicle Invasiveness Stool examination

PCR

Washing cooking

food personal hygiene

TMP-SMZ Usually No ndash

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

ldquoStreptococcus

pyrogenes (lysogenized)

Droplet contact direct contact Erythrogenic toxin

Examination of skin lesions

throat culture (beta- hemolytic on blood agar

sensitive to bacitracin rapid antigen tests)

Hygiene practicesPenicillin

cephalexin in penicillin- allergic

Sandpaper feel to affected ski

severe sore throat

Warts Human papillomaviruses

Direct contact autoinoculation indirect contact

naClinical diagnosis

also histology microscopy PCR

Avoid contactHome treatment cryosurgery (virus

not eliminated)na

Molluscum contagiosum

Molluscum contagiosum

viruses

Direct contact including sexual

contact autoinoculation

na ldquo ldquo

Usually none but mechanical

removal can be performed

na

Leishmaniasis Leishmania spp Biological vector Multiplication with macrophages

Culture of protozoa

microscopic visualization

Avoiding sand fly Sodium stibogluconate

Mucocutaneous and systemic

forms

Cutaneous Anthrax Bacillus anthracis Direct contact

with endospores

Endospore formation

capsule lethal amp edema factor

Culture on blood agar serology

PCR performed by CDC

Avoid contact vaccine available

but not widely used

Ciprofloxacin doxycycline levofloxacin

Can be fatal

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Cutaneous Infections

Trichophyton Microsporum

Epidermophyton

Direct and indirect contact

vehicle (soil)

Ability to degrade keratin invoke hypersensitivity

Microscopic examination KOH staining

culture

Avoid contact

Topical tolnaftate

itraconazole terbinafine miconazole

thiabendazine

na

Superficial Infections (Tinea

versicolor)Malassezia furfur Endogenous

ldquonormal biotardquo na Usually clinical KOH can be used na Topical

antifungals na

Neonatal conjunctivitis

Chlamydia trachomatis or

Neisseria gonorrhoea

Vertical na Gram stain and culture

Screen mothers apply antibiotic or silver nitrate

to newborn eyes

Topical and oral antibiotics

In babies lt 28 days old

Bacterial conjunctivitis

S pyrogenes S pneumonia

Staphylococcus aureus

Haemophilus

Direct indirect contact

na Clinical diagnosis Hygiene Broad- spectrum topical antibiotic

often ciprofloxacin

Mucopurulent discharge

influenza Moraxella and

also N gonorrhea C trachomatis

Viral conjunctivitis

Adenoviruses and others ldquo na ldquo ldquo

None although antibiotics often given because

type of infection not distinguished

Serous (clear) discharge

Trachoma C trachomatis serovars A- C

Indirect contact mechanical

vector

Intracellular growth

Detection of inclusion bodies

in stained preparations

Hygiene vector control prompt

treatment of initial infection

Azithromycin or topical

erythromycinna

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Keratitis Herpes simplex virus

Reactivation of latent virus

although primary infections can

occur in the eye

Latency

Usually clinical diagnosis viral culture or PCR if

needed

naTopical

trifluridine andor oral acyclovir

na

Miscellaneous microorganisms

Often traumatic introduction (parenteral)

Various Various na Specific antimicrobials na

River blindnessWolbachia plus

Onchocerca volvulus

Biological vectorInduction of

inflammatory response

ldquoSkin snipsrdquo small piece of

skin in NaCl solrsquon examined under microscope and

microfilariae counted

Avoiding black fly Ivermectin Worms often visible in eye

Summing Up

Microorganism DiseaseGram positive bacteria Acne

Impetigo cellulitis scalded skin syndromeImpetigo cellulitisGas gangreneCutaneous anthrax

Gram negative bacteria Neonatal conjunctivitisNeonatal conjunctivitis trachomaRiver blindness

DNA Viruses Chickenpox smallpox fifth disease roseola warts molluscum contagiosum keratitis

RNA Viruses Measles rubellaFungi Ringworm superficial mycosisProtozoa LeishmaniasisHelminths River blindness

Chapter 19 Infectious Diseases Affecting the Nervous System

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

FeaturesMeningitis

Neisseria meningitidis Droplet contact

Capsule endotoxin IgA

protease

Gram stain culture of CSF

blood rapid antigenic tests

Conjugated vaccine

rifampin or tetracycline

used to protect contacts

Penicillin G orCefotaxime

Petechiae meningo- coccemia

Streptococcus pneumoniae Droplet contact

Capsule induction of apoptosis

hemolysin and hydrogen peroxide

production

Gram stain culture of CSF

Two vaccines Prevnar

(children) and Pneumovax

(adults)

Cefotaxime check for

resistance (add vancomycin in

that case)

Serious acute most common meningitis in

adults

Haemophilus influenzae Droplet contact Capsule

Culture on chocolate agar Hib vaccine Cefotaxime

Serious acute less common since

vaccine became available

Listeria monocytogenes Vehicle (food) Intracellular

growth

Cold enrichment

rapid methods

Cooking food avoiding

unpasteurized dairy products

Ampicillin trimethoprim- sulfamethox-

azole

Asymptomatic in healthy adults

meningitisin neonates elderly

and immuno- compromised

Cryptococcus neoformans

Vehicle (air dust soil)

Capsule melanin

production

Negative staining

biochemical tests DNA

probes

naAmphotericin B and fluconazole

Acute or chronic most common in AIDS

patients

Coccidioides immitis

Vehicle (air dust soil)

Granuloma (spherule) formation

Identification of spherules

cultivation on Sabouraudrsquos

agar

Avoiding airborne spores

Amphotericin B or oral or IV itraconazole

Almost exlusively in endemic regions

Viruses Droplet contact Lytic infection Initially absence na Usually none Generally milder than

of host cells

of bacteriafungi

protozoa followed by viral

culture or antigen tests

unless specific virus identified

and specific antiviral exists)

bacterial or fungal

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Neonatal Meningitis

Streptococcus agalactiae Vertical (during

birth) Capsule

Culture motherrsquos genital tract on blood agar CSF

culture of neonate

Culture and treatment of

mother

Penicillin G plus aminoglycosides

Most common positive culture of mother confirms

diagnosis

Escherichia coli strain K1 Vertical (during

birth) ndash CSF Gram stainculture ndash Cefotaxime plus

aminoglycosideSuspected if infant is

premature

Listeria monocytogenes Vertical Intracellular

growth

Cold enrichment

rapid methods

Cooking food avoiding

unpasteurized dairy products

Ampicillin trimethoprim-

sulfamethoxazole

Suspected if infant is premature

Meningo-encephalitis

Primary Amoebic Meningoencephaliti

sNaegleria fowleri

Vehicle (exposure while

swimming in water)

InvasivenessExamination of

CSF brain imaging

Avoid warm fresh water

Amphotericin B mostly

ineffective

Granulomatous Amoebic

Meningoencephalitis

Acanthamoeba

Direct contact InvasivenessExamination of

CSF brain imaging

ndash

Surgical excision of granulomas Ketoconazole

may help

Meningitis Arboviruses (viruses causing WEE EEE

California encephalitis SLE

West Nile encephalitis)

Vector (arthropod

bites)

Attachment fusion invasion

capabilities

History rapid serological tests

Insect control vaccines for WEE and EEE

available

None History of exposure to insect important

Herpes simplex 1 or 2

Vertical or reactivation of latent infection

ndash

Clinical presentation PCR Ab tests growth of virus in cell culture

Maternal screening for

HSVAcyclovir

In infants disseminated disease present rare between

30 and 50 years

JC virus Ubiquitous ndashPCR of

cerebrospinal fluid

None Zidovudine or other antivirals

In severely immunocompromised

especially AIDSImmunologic

reaction to other viral infections

Sequelae of measles other viral infections

and occasionally

ndash History of viral infection or vaccination

ndash Steroids anti-inflammatory

agents

History of virusvaccine

exposure critical

vaccination

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing Features

Subacute Encephalitis

Toxoplasma gondii Vehicle (meat) or fecal-oral

Intracellular growth

Serological detection of IgM

Personal hygiene food

hygiene

Pyrimethamine andor

sulfadiazine

Subacute slower development of disease

Subacute sclerosing panencephalitis

Persistence of measles virus

Cell fusion evasion of immune system

EEGs None None History of measles

Prions

CJD= directparenteral

contact with infected tissue

or inherited vCJD= vehicle

(meat parenteral)

Avoidance of host immune

responseBiopsy Avoiding tissue None Long incubation period fast

progression once it begins

Rabies Rabies virusParenteral (bite trauma) droplet

contact

Envelope glycoprotein

RT-PCR of saliva Ab detection of serum or CSF

skin biopsy

HDCVmdashinactivated

vaccine

Postexposure passive and

active immunization

na

Poliomyelitis Poliovirus Fecal-oral vehicle

Attachment mechanisms

Viral culture serology

Live attenuated (developing

world) or inactivated

vaccine (developed

world)

None palliative supportive

Tetanus Clostridium tetani Parenteral direct contact

Tetanospasm exotoxin Symptomatic Tetanus toxoid

immunization

Combination of passive antitoxin

and tetanus toxoid active

immunization supportive

na

Botulism Clostridium botulinum

Vehicle (food-borne toxin

airborne organism) direct contact (wound)

parenteral (injection)

Botulinum exotoxin

Culture of organism

demonstration of toxin

Food hygiene toxoid

immunization available for laboratory

professionals

Antitoxin supportive care na

African Sleeping Sickness

Trypanosoma brucei subspecies

gambiense or rhodesiense

Vector verticalImmune

evasion by antigen shifting

Microscopic examination of

blood CSFVector control

Suramin or pentamidine

(early) melarsoprol

(late)

Chapter 20 Infectious Diseases Affecting the Cardiovascular and lymphatic systems

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Acute Endocarditis

Staphylococcus aureus Parenteral Attachment Blood culture Aseptic surgery

injections

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Acute onset high fatality rate

Subacute Endocarditis

Alpha-hemolytic streptococci

Endogenous transfer of

normal biota to bloodstream

Attachment Blood culture

Prophylactic antibiotics before

invasive procedures

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Slower onset

Septicemia Bacteria or fungiParenteral

endogenous transfer

Cell wall or membrane

componentsBlood culture -

Broad-spectrum antibiotic until

identification and susceptibilities

tested

Plague Yersinia pestis

Vector biological also droplet contact

(pneumonic) and direct contact

with body fluids

Capsule Yop system

plasminogen activator

Culture or Gram stain of blood or bubo aspirate

Flea and or animal control

vaccine available for high-risk individuals

Streptomycin or gentamicin

Tularemia Francisella tularensis

Vector biological also direct contact

with body fluids from infected

animal airborne

Intracellular growth

Culture dangerous to lab workers and not reliable serology most often used

Live attenuated vaccine for high-risk individuals

Gentamicin or streptomycin

Lyme Disease Borrelia burgdorferi Vector biological Antigenic shifting adhesins

ELISA for Ab PCR Tick avoidance

Doxycycline andor amoxicillin (3ndash4

weeks) also cephalosporins and

penicillin

Infectious Mononucleosis

Epstein-Barr virus (EBV)

Direct indirect contact

parenteral

Latency ability to incorporate into

host DNA

Differential blood count Monospot

test for heterophile antibody

specific ELISA

ndash Supportive Most common in teens

Cytomegalovirus (CMV)

Direct indirect contact

parenteral vertical

Latency ability to fuse cells

Virus isolation and growth ELISA or PCR

tests

Vaccine in trials

Only for immunosuppressed

patients not usually for

mononucleosis

More common in adults dangerous to

fetus

Hemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Yellow fever Yellow fever virus Biological vector Disruption of clotting factors ELISA PCR Live attenuated

vaccine available Supportive Accompanied by jaundice

Dengue Fever Dengue fever virus Biological vector Disruption of clotting factors Rise in IgM titers

Live attenuated vaccine being

testedSupportive

ldquoBreakbone feverrdquomdashso named due to

severe pain

Ebola andor Marburg

Ebola virus Marburg virus

Direct contact body fluids

Disruption of clotting factors

PCR viral culture (conducted at

CDC)ndash Supportive

Massive hemorrhage rash

sometimes present

Lassa Fever Lassa fever virus

Droplet contact (aerosolized

rodent excretions)

direct contact with infected

fluids

Disruption of clotting factors ELISA Avoiding rats

safe food storage RibavirinChest pain

deafness as long-term sequelae

Nonhemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Brucellosis Brucella abortus or B suis

Direct contact airborne

parenteral (needlesticks)

Intracellular growth

avoidance of destruction by

phagocytes

Gram stain of biopsy material

Animal control pasteurization of

milk

Doxycycline plus (gentamicin or streptomycin)

Undulating fever muscle aches

Q fever Coxiella burnetii Airborne direct contact

Endosporelike structure

Serological tests for antibody

Vaccine for high-risk population Doxycycline

Airborne route of transmission

variable disease presentation

Cat-Scratch Disease Bartonella henselae food-borne Endotoxin

Biopsy of lymph nodes plus Gram staining ELISA (performed by

CDC)

Clean wound sites Azithromycin

History of cat bite or scratch fever not

always present

Trench Fever Bartonella quintana Parenteral (cat scratch or bite) Endotoxin

ELISA (performed by

CDC)Avoid lice Doxycycline or

erythromycin

Endocarditis common 5-day

fever

Ehrlichioses Ehrlichia species Biological vector (lice) - PCR indirect

antibody test Avoid lice Doxycycline Seasonal occurrence (AprilndashOct)

Rocky Mountain

Spotted FeverRickettsia rickettsii Biological vector

(tick)

Induces apoptosis in cells

lining blood vessels

Fluorescent antibody PCR Avoid lice Doxycycline

Most common in east and southeast

United States

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

MalariaPlasmodium

falciparum P vivax P ovale P malariae

Biological vector (mosquito)

vertical

Multiple life stages multiple antigenic types

ability to scavenge

glucose GPI cytoadherence

Blood smear serological methods

Mosquito control use of bed nets no vaccine yet

available prophylactic antiprotozoal

agents

Chloroquine mefloquine artemisinin

Fansidar quinine or proguanil

Anthrax Bacillus anthracis

Vehicle (air soil) indirect contact (animal hides) vehicle (food)

Triple exotoxin capsule

Culture direct fluorescent

antibody tests

Vaccine for high-risk population postexposure

antibiotic prophylaxis

Doxycycline ciprofloxacin

penicillin

HIV Infection and AIDS

Human immunodeficiency

virus 1 or 2

Direct contact (sexual)

parenteral (blood-borne)

vertical (perinatal and via breast

milk)

Attachment syncytia

formation reverse

transcriptase high mutation

rate

Initial screening for antibody followed by

Western blot confirmation of

antibody

Avoidance of contact with infected sex

partner contaminated blood breast

milk

HAART (reverse transcriptase inhibitors plus

protease inhibitors) Fuzeon nonnucleoside RT

inhibitors

Adult T-Cell Leukemia HTLV-I

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Hairy-Cell Leukemia (Possibly) HTLV-II

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Chapter 21 Infectious disease affecting the respiratory system

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Rhinitis Approximately 200 viruses

Indirect contact droplet contact

Attachment proteins most

symptoms induced by host

response

Not necessary Hygiene practices For symptoms only

Sinusitis Various bacteria often mixed

infection

Endogenous (opportunism)

Culture not usually

performed diagnosis based

Broad-spectrum antibiotics

Much more common than fungal

on clinical presentation occasionally X rays or other

imaging technique used

Various fungi

Introduction by trauma or

opportunisticOvergrowrth

Same

Physical removal of fungus in severe cases antifungals

used

Suspect in immunocompromised

patients

Otitis Media

Streptococcus pneumoniae

Endogenous (may follow

upper respiratory tract infection by S pneumoniae or

other microorganisms)

Capsule hemolysin

Usually relies on clinical

symptoms and failure to resolve within 72 hours

Pneumococcal conjugate vaccine

(heptavalent)

Wait for resolution if needed

amoxicillin (are high rates of resistance) or amoxicillin 1113106

clavalanate or cefuroxine

ndash

Haemophilus influenzae

Endogenous (follows upper

respiratory tract infection)

Capsule fimbriae Same Hib vaccine Same as for S pneumoniae ndash

Other bacteria Endogenous ndash Same None

Wait for resolution if needed a broad-spectrum antibiotic

(azithromycin) might be used in

absence of etiologic diagnosis

Suspect if fully vaccinated against

other two

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Pharyngitis

Streptococcus pyogenes

Droplet or direct contact

LTA M protein hyaluronic acid

capsule SLS and SLO

superantigens

Beta-hemolytic on blood agar sensitive to bacitracin rapid

antigen tests

Hygiene practices

Penicillin cephalexin in

penicillin-allergic

Generally more severe than viral

pharyngitis

Viruses All forms of contact ndash

Goal is to rule out S pyogenes further diagnosis usually

not performed

Hygiene practices

Symptom relief only

Hoarseness frequently

accompanies viral pharyngitis

Diphtheria Corynebacterium diphtheriae

Droplet contact direct contact or indirect contact

with contaminated

Exotoxin diphtheria toxin

Tellurite mediummdashgrayblack colonies

club-shaped morphology on

Gram stain

Diphtheria toxoid vaccine (part of

DTaP)

Antitoxin plus penicillin or

erythromycin

fomitestreatment begun before definitive

identification

Pertussis (Whooping

Cough)

Bordetella pertussis Droplet contact

FHA (adhesion) pertussis toxin and tracheal

cytotoxin endotoxin

Grown on B-G charcoal or potato-

glycerol agar diagnosis can be

made on symptoms

Acellular vaccine (DTaP)

erythromycin or trimethoprim-

sulfamethoxazole for contacts

Mainly supportive erythromycin to

decrease communicability

RSV DiseaseRespiratory

syncytial virus (RSV)

Droplet and indirect contact

Syncytia formation

Direct antigen testing

Passive antibody in high-risk

children

Ribavirin in severe cases

Influenza Influenza A B and C viruses

Droplet contact direct contact some indirect

contact

Glycoprotein spikes overall

ability to change genetically

Viral culture (3ndash10 days) or rapid

antigen-based or PCR tests

Killed injected vaccine or inhaled live attenuated

vaccinemdashtaken annually

Amantadine rimantadine zanamivir or oseltamivir

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Tuberculosis

Mycobacterium tuberculosis

Vehicle (airborne)

Lipids in wall ability to

stimulate strong cell-mediated

immunity (CMI)

Rapid methods plus culture initial tests are skin testing and

chest X ray

Avoiding airborne M

tuberculosis BCG vaccine in other countries

Isoniazid rifampin and pyrazinamide 1113106 ethambutol or streptomycin for

varying lengths of time (always lengthy) if

resistant two other drugs added

to regimen

Responsible for nearly all TB except

for HIV

Mycobacterium avium complex

Vehicle (airborne) ndash Positive blood

culture

Rifabutin or azithromycin given to AIDS

patients at risk

Azithromycin or clarithromycin plus

one additional antibiotic

Suspect this in HIV-positive patients

PneumoniaStreptococcus pneumoniae

Droplet contact or endogenous

transferCapsule

Gram stain often diagnostic alpha-

hemolytic on blood agar

Pneumococcal polysaccharide

vaccine (23-valent)

Cefotaxime ceftriaxone ketek much resistance

Patient usually severely ill

Legionella species Vehicle (water droplets) ndash

Requires selective charcoal yeast extract agar

serology unreliable

ndashFluoroquinolone

azithromycin clarithromycin

Mild pneumonias in healthy people can be severe in elderly

or immunocompromised

Mycoplasma pneumoniae

Droplet contact Adhesins Rule out other etiologic agents

No vaccine no permanent immunity

Recommended not to treat in most

cases doxycycline or macrolides may

be used if

Usually mild ldquowalking pneumoniardquo

necessary

Hantavirus

Vehiclemdashairborne virus emitted from

rodents

Ability to induce inflammatory

response

Serology (IgM) PCR identification of antigen in tissue

Avoid mouse habitats and

droppingsSupportive Rapid onset high

mortality rate

SARS-associated coronavirus

Droplet direct contact

Rule out other agents serology

PCRndash Supportive Rapid onset

Histoplasma capsulatum

Vehiclemdashinhalation of

contaminated soil

Survival in phagocytes

Usually serological (rising Ab titers)

Avoid contaminated soil bat bird

droppings

Amphotericin B andor itraconazole

Many infections asymptomatic

Pneumocystis jiroveci Droplet contact ndash Immunofluorescence

Antibiotics given to AIDS patients to prevent this

Trimethoprim- sulfamethoxazole

Vast majority occur in AIDS patients

Nosocomial Pneumonia

Gram-negative and gram-positive

bacteria from upper respiratory tract or stomach

Endogenous (aspiration) Culture of lung fluids

Elevating patientrsquos head preoperative

education care of respiratory

equipment

Broad-spectrum antibiotics

Chapter 22 Infectious diseases affecting the GIT

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Dental CariesStreptococcus mutans Streptococcus sobrinus

othersDirect contact Adhesion acid

production -Oral hygiene

fluoride supplementation

Removal of diseased tooth

material

Periodontitis

Polymicrobial community including

some or all of Tannerella forsythus

Actinobacillus actinomycetemcomitans

Porphyromonas gingivalis others

Induction of inflammation Oral hygiene

Removal of plaque and calculus gum

reconstruction tetracycline

Necrotizing Ulcerative

Gingivitis and Periodontitis

Polymicrobial community (Treponema

vincentii Prevotella intermedia

Fusobacterium species)

Inflammation Oral hygiene

Debridement of damaged tissue metronidazole

clindamycin

Mumps Mumps virus (genus Paramyxovirus) Droplet contact

Spike-induced syncytium formation

Clinical fluorescent Ag tests ELISA for

Ab

MMR live attenuated

vaccineSupportive

Gastritis and Helicobacter pylori Adhesions ELISA None Antibiotics plus

Gastric Ulcers urease endoscopy

acid suppressors (clarithromycin or

metronidazole plus omeprazole

or bismuth subsalicylate)

DiseaseAcute

Diarrhea

Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

Features

Bacterial Causes

SalmonellaVehicle (food

beverage) fecal-oral

Adhesins endotoxin

Stool culture not

usually necessary

Food hygiene and

personal hygiene

Rehydration no antibiotic

for uncomplicated

disease

Usually Sometimes

Often associated

with chickens reptiles

Shigella Fecal-oral

Endotoxin enterotoxin

shiga toxins in some strains

Stool culture antigen

testing for shiga toxin

Food hygiene and

personal hygiene

TMP-SMZ rehydration Often Often Very low

ID50

Shiga-toxin- producing E coli O157H7 (EHEC)

Vehicle (food beverage) fecal-

oral

Shiga toxins proteins for attachment secretion

effacement

Stool culture antigen

testing for shiga toxin

Avoid live E coli (cook meat and

clean vegetables)

Antibiotics contraindicated supportive

measures

Often UsuallyHemolytic

uremic syndrome

Other E coli (non-shiga-toxin- producing)

Vehicle fecal-oral

Various proteins for attachment secretion

effacement heat-labile

andor heat- stable

exotoxins invasiveness

Stool culture not usually

necessary in absence of blood fever

Food and personal hygiene

Rehydration Sometimes SometimesEIEC ETEC EPEC

Campylobacter Vehicle (food water) fecal-oral

Adhesins exotoxin

induction of autoimmunity

Stool culture not usually necessary dark-field

microscopy

Food and personal hygiene

Rehydration erythromycin

in severe cases

(antibiotic resistance

rising)

Usually NoGuillain-

Barreacute syndrome

Yersinia Vehicle (food Intracellular Cold- Food and None in most Usually Occasionall Severe

water) fecal-oral indirect contact growth enrichment

stool culturepersonal hygiene

cases doxycycline or TMP-SMZ for bacteremia

y abdominal pain

Clostridium difficile

Endogenous (normal biota)

Enterotoxins A and B

Stool culture PCR

ELISA demonstration of toxins

in stool

ndash

Withdrawal of antibiotic in severe cases

metronidazole or vancomycin

SometimesNot

usually mucus

Antibiotic- associated diarrhea

Vibrio choleraeVehicle (water

and some foods) fecal-oral

Cholera toxin (CT)

Clinical diagnosis

microscopic techniques serological detection of

antitoxin

Water hygiene

Rehydration in severe

cases tetracycline

TMP-SMZ

No prominent Rice-water stools

Non-bacterial causes

Cryptosporidium Vehicle (water food) fecal-oral

Intracellular growth

Acid-fast staining ruling out bacteria

Water treatment proper food

handling

None paromomycin

used sometimes

Often Not usually

Resistant to chlorine disinfectio

n

Rotavirus Fecal-oral vehicle fomite ndash Usually not

performedOral live

virus vaccine Rehydration Often No Severe in babies

Other Viruses Fecal-oral vehicle - Usually not performed Hygiene Rehydration Sometimes No

Acute Diarrhea

with Vomiting

(Food Poisoning)

Staphylococcus aureus exotoxin

Vehicle (food)

Heat-stable exotoxin

Usually based on

epidemiological evidence

Proper food handling None Not Usually No

Suspect in foods with high salt or

sugar content

Bacillus cereusHeat-stable toxin heat-labile toxin

Microscopic analysis of

food or stool

Two forms emetic and diarrheal

Clostridium perfringens

Heat-labile toxin

Detection of toxin in stool

Acute abdominal

pain

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

FeaturesChronic Diarrhea Enteroaggregativ

e E coli (EAEC)Vehicle (food

water) fecal-oral

Difficult to distinguish

from other E coli

None or ciprofloxacin No

Sometimes mucus

also

Chronic in the

malnourished

Cyclospora cayetanensis

Fecal-oral vehicle Invasiveness Stool examination

PCR

Washing cooking

food personal hygiene

TMP-SMZ Usually No ndash

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

influenza Moraxella and

also N gonorrhea C trachomatis

Viral conjunctivitis

Adenoviruses and others ldquo na ldquo ldquo

None although antibiotics often given because

type of infection not distinguished

Serous (clear) discharge

Trachoma C trachomatis serovars A- C

Indirect contact mechanical

vector

Intracellular growth

Detection of inclusion bodies

in stained preparations

Hygiene vector control prompt

treatment of initial infection

Azithromycin or topical

erythromycinna

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Keratitis Herpes simplex virus

Reactivation of latent virus

although primary infections can

occur in the eye

Latency

Usually clinical diagnosis viral culture or PCR if

needed

naTopical

trifluridine andor oral acyclovir

na

Miscellaneous microorganisms

Often traumatic introduction (parenteral)

Various Various na Specific antimicrobials na

River blindnessWolbachia plus

Onchocerca volvulus

Biological vectorInduction of

inflammatory response

ldquoSkin snipsrdquo small piece of

skin in NaCl solrsquon examined under microscope and

microfilariae counted

Avoiding black fly Ivermectin Worms often visible in eye

Summing Up

Microorganism DiseaseGram positive bacteria Acne

Impetigo cellulitis scalded skin syndromeImpetigo cellulitisGas gangreneCutaneous anthrax

Gram negative bacteria Neonatal conjunctivitisNeonatal conjunctivitis trachomaRiver blindness

DNA Viruses Chickenpox smallpox fifth disease roseola warts molluscum contagiosum keratitis

RNA Viruses Measles rubellaFungi Ringworm superficial mycosisProtozoa LeishmaniasisHelminths River blindness

Chapter 19 Infectious Diseases Affecting the Nervous System

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

FeaturesMeningitis

Neisseria meningitidis Droplet contact

Capsule endotoxin IgA

protease

Gram stain culture of CSF

blood rapid antigenic tests

Conjugated vaccine

rifampin or tetracycline

used to protect contacts

Penicillin G orCefotaxime

Petechiae meningo- coccemia

Streptococcus pneumoniae Droplet contact

Capsule induction of apoptosis

hemolysin and hydrogen peroxide

production

Gram stain culture of CSF

Two vaccines Prevnar

(children) and Pneumovax

(adults)

Cefotaxime check for

resistance (add vancomycin in

that case)

Serious acute most common meningitis in

adults

Haemophilus influenzae Droplet contact Capsule

Culture on chocolate agar Hib vaccine Cefotaxime

Serious acute less common since

vaccine became available

Listeria monocytogenes Vehicle (food) Intracellular

growth

Cold enrichment

rapid methods

Cooking food avoiding

unpasteurized dairy products

Ampicillin trimethoprim- sulfamethox-

azole

Asymptomatic in healthy adults

meningitisin neonates elderly

and immuno- compromised

Cryptococcus neoformans

Vehicle (air dust soil)

Capsule melanin

production

Negative staining

biochemical tests DNA

probes

naAmphotericin B and fluconazole

Acute or chronic most common in AIDS

patients

Coccidioides immitis

Vehicle (air dust soil)

Granuloma (spherule) formation

Identification of spherules

cultivation on Sabouraudrsquos

agar

Avoiding airborne spores

Amphotericin B or oral or IV itraconazole

Almost exlusively in endemic regions

Viruses Droplet contact Lytic infection Initially absence na Usually none Generally milder than

of host cells

of bacteriafungi

protozoa followed by viral

culture or antigen tests

unless specific virus identified

and specific antiviral exists)

bacterial or fungal

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Neonatal Meningitis

Streptococcus agalactiae Vertical (during

birth) Capsule

Culture motherrsquos genital tract on blood agar CSF

culture of neonate

Culture and treatment of

mother

Penicillin G plus aminoglycosides

Most common positive culture of mother confirms

diagnosis

Escherichia coli strain K1 Vertical (during

birth) ndash CSF Gram stainculture ndash Cefotaxime plus

aminoglycosideSuspected if infant is

premature

Listeria monocytogenes Vertical Intracellular

growth

Cold enrichment

rapid methods

Cooking food avoiding

unpasteurized dairy products

Ampicillin trimethoprim-

sulfamethoxazole

Suspected if infant is premature

Meningo-encephalitis

Primary Amoebic Meningoencephaliti

sNaegleria fowleri

Vehicle (exposure while

swimming in water)

InvasivenessExamination of

CSF brain imaging

Avoid warm fresh water

Amphotericin B mostly

ineffective

Granulomatous Amoebic

Meningoencephalitis

Acanthamoeba

Direct contact InvasivenessExamination of

CSF brain imaging

ndash

Surgical excision of granulomas Ketoconazole

may help

Meningitis Arboviruses (viruses causing WEE EEE

California encephalitis SLE

West Nile encephalitis)

Vector (arthropod

bites)

Attachment fusion invasion

capabilities

History rapid serological tests

Insect control vaccines for WEE and EEE

available

None History of exposure to insect important

Herpes simplex 1 or 2

Vertical or reactivation of latent infection

ndash

Clinical presentation PCR Ab tests growth of virus in cell culture

Maternal screening for

HSVAcyclovir

In infants disseminated disease present rare between

30 and 50 years

JC virus Ubiquitous ndashPCR of

cerebrospinal fluid

None Zidovudine or other antivirals

In severely immunocompromised

especially AIDSImmunologic

reaction to other viral infections

Sequelae of measles other viral infections

and occasionally

ndash History of viral infection or vaccination

ndash Steroids anti-inflammatory

agents

History of virusvaccine

exposure critical

vaccination

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing Features

Subacute Encephalitis

Toxoplasma gondii Vehicle (meat) or fecal-oral

Intracellular growth

Serological detection of IgM

Personal hygiene food

hygiene

Pyrimethamine andor

sulfadiazine

Subacute slower development of disease

Subacute sclerosing panencephalitis

Persistence of measles virus

Cell fusion evasion of immune system

EEGs None None History of measles

Prions

CJD= directparenteral

contact with infected tissue

or inherited vCJD= vehicle

(meat parenteral)

Avoidance of host immune

responseBiopsy Avoiding tissue None Long incubation period fast

progression once it begins

Rabies Rabies virusParenteral (bite trauma) droplet

contact

Envelope glycoprotein

RT-PCR of saliva Ab detection of serum or CSF

skin biopsy

HDCVmdashinactivated

vaccine

Postexposure passive and

active immunization

na

Poliomyelitis Poliovirus Fecal-oral vehicle

Attachment mechanisms

Viral culture serology

Live attenuated (developing

world) or inactivated

vaccine (developed

world)

None palliative supportive

Tetanus Clostridium tetani Parenteral direct contact

Tetanospasm exotoxin Symptomatic Tetanus toxoid

immunization

Combination of passive antitoxin

and tetanus toxoid active

immunization supportive

na

Botulism Clostridium botulinum

Vehicle (food-borne toxin

airborne organism) direct contact (wound)

parenteral (injection)

Botulinum exotoxin

Culture of organism

demonstration of toxin

Food hygiene toxoid

immunization available for laboratory

professionals

Antitoxin supportive care na

African Sleeping Sickness

Trypanosoma brucei subspecies

gambiense or rhodesiense

Vector verticalImmune

evasion by antigen shifting

Microscopic examination of

blood CSFVector control

Suramin or pentamidine

(early) melarsoprol

(late)

Chapter 20 Infectious Diseases Affecting the Cardiovascular and lymphatic systems

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Acute Endocarditis

Staphylococcus aureus Parenteral Attachment Blood culture Aseptic surgery

injections

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Acute onset high fatality rate

Subacute Endocarditis

Alpha-hemolytic streptococci

Endogenous transfer of

normal biota to bloodstream

Attachment Blood culture

Prophylactic antibiotics before

invasive procedures

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Slower onset

Septicemia Bacteria or fungiParenteral

endogenous transfer

Cell wall or membrane

componentsBlood culture -

Broad-spectrum antibiotic until

identification and susceptibilities

tested

Plague Yersinia pestis

Vector biological also droplet contact

(pneumonic) and direct contact

with body fluids

Capsule Yop system

plasminogen activator

Culture or Gram stain of blood or bubo aspirate

Flea and or animal control

vaccine available for high-risk individuals

Streptomycin or gentamicin

Tularemia Francisella tularensis

Vector biological also direct contact

with body fluids from infected

animal airborne

Intracellular growth

Culture dangerous to lab workers and not reliable serology most often used

Live attenuated vaccine for high-risk individuals

Gentamicin or streptomycin

Lyme Disease Borrelia burgdorferi Vector biological Antigenic shifting adhesins

ELISA for Ab PCR Tick avoidance

Doxycycline andor amoxicillin (3ndash4

weeks) also cephalosporins and

penicillin

Infectious Mononucleosis

Epstein-Barr virus (EBV)

Direct indirect contact

parenteral

Latency ability to incorporate into

host DNA

Differential blood count Monospot

test for heterophile antibody

specific ELISA

ndash Supportive Most common in teens

Cytomegalovirus (CMV)

Direct indirect contact

parenteral vertical

Latency ability to fuse cells

Virus isolation and growth ELISA or PCR

tests

Vaccine in trials

Only for immunosuppressed

patients not usually for

mononucleosis

More common in adults dangerous to

fetus

Hemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Yellow fever Yellow fever virus Biological vector Disruption of clotting factors ELISA PCR Live attenuated

vaccine available Supportive Accompanied by jaundice

Dengue Fever Dengue fever virus Biological vector Disruption of clotting factors Rise in IgM titers

Live attenuated vaccine being

testedSupportive

ldquoBreakbone feverrdquomdashso named due to

severe pain

Ebola andor Marburg

Ebola virus Marburg virus

Direct contact body fluids

Disruption of clotting factors

PCR viral culture (conducted at

CDC)ndash Supportive

Massive hemorrhage rash

sometimes present

Lassa Fever Lassa fever virus

Droplet contact (aerosolized

rodent excretions)

direct contact with infected

fluids

Disruption of clotting factors ELISA Avoiding rats

safe food storage RibavirinChest pain

deafness as long-term sequelae

Nonhemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Brucellosis Brucella abortus or B suis

Direct contact airborne

parenteral (needlesticks)

Intracellular growth

avoidance of destruction by

phagocytes

Gram stain of biopsy material

Animal control pasteurization of

milk

Doxycycline plus (gentamicin or streptomycin)

Undulating fever muscle aches

Q fever Coxiella burnetii Airborne direct contact

Endosporelike structure

Serological tests for antibody

Vaccine for high-risk population Doxycycline

Airborne route of transmission

variable disease presentation

Cat-Scratch Disease Bartonella henselae food-borne Endotoxin

Biopsy of lymph nodes plus Gram staining ELISA (performed by

CDC)

Clean wound sites Azithromycin

History of cat bite or scratch fever not

always present

Trench Fever Bartonella quintana Parenteral (cat scratch or bite) Endotoxin

ELISA (performed by

CDC)Avoid lice Doxycycline or

erythromycin

Endocarditis common 5-day

fever

Ehrlichioses Ehrlichia species Biological vector (lice) - PCR indirect

antibody test Avoid lice Doxycycline Seasonal occurrence (AprilndashOct)

Rocky Mountain

Spotted FeverRickettsia rickettsii Biological vector

(tick)

Induces apoptosis in cells

lining blood vessels

Fluorescent antibody PCR Avoid lice Doxycycline

Most common in east and southeast

United States

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

MalariaPlasmodium

falciparum P vivax P ovale P malariae

Biological vector (mosquito)

vertical

Multiple life stages multiple antigenic types

ability to scavenge

glucose GPI cytoadherence

Blood smear serological methods

Mosquito control use of bed nets no vaccine yet

available prophylactic antiprotozoal

agents

Chloroquine mefloquine artemisinin

Fansidar quinine or proguanil

Anthrax Bacillus anthracis

Vehicle (air soil) indirect contact (animal hides) vehicle (food)

Triple exotoxin capsule

Culture direct fluorescent

antibody tests

Vaccine for high-risk population postexposure

antibiotic prophylaxis

Doxycycline ciprofloxacin

penicillin

HIV Infection and AIDS

Human immunodeficiency

virus 1 or 2

Direct contact (sexual)

parenteral (blood-borne)

vertical (perinatal and via breast

milk)

Attachment syncytia

formation reverse

transcriptase high mutation

rate

Initial screening for antibody followed by

Western blot confirmation of

antibody

Avoidance of contact with infected sex

partner contaminated blood breast

milk

HAART (reverse transcriptase inhibitors plus

protease inhibitors) Fuzeon nonnucleoside RT

inhibitors

Adult T-Cell Leukemia HTLV-I

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Hairy-Cell Leukemia (Possibly) HTLV-II

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Chapter 21 Infectious disease affecting the respiratory system

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Rhinitis Approximately 200 viruses

Indirect contact droplet contact

Attachment proteins most

symptoms induced by host

response

Not necessary Hygiene practices For symptoms only

Sinusitis Various bacteria often mixed

infection

Endogenous (opportunism)

Culture not usually

performed diagnosis based

Broad-spectrum antibiotics

Much more common than fungal

on clinical presentation occasionally X rays or other

imaging technique used

Various fungi

Introduction by trauma or

opportunisticOvergrowrth

Same

Physical removal of fungus in severe cases antifungals

used

Suspect in immunocompromised

patients

Otitis Media

Streptococcus pneumoniae

Endogenous (may follow

upper respiratory tract infection by S pneumoniae or

other microorganisms)

Capsule hemolysin

Usually relies on clinical

symptoms and failure to resolve within 72 hours

Pneumococcal conjugate vaccine

(heptavalent)

Wait for resolution if needed

amoxicillin (are high rates of resistance) or amoxicillin 1113106

clavalanate or cefuroxine

ndash

Haemophilus influenzae

Endogenous (follows upper

respiratory tract infection)

Capsule fimbriae Same Hib vaccine Same as for S pneumoniae ndash

Other bacteria Endogenous ndash Same None

Wait for resolution if needed a broad-spectrum antibiotic

(azithromycin) might be used in

absence of etiologic diagnosis

Suspect if fully vaccinated against

other two

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Pharyngitis

Streptococcus pyogenes

Droplet or direct contact

LTA M protein hyaluronic acid

capsule SLS and SLO

superantigens

Beta-hemolytic on blood agar sensitive to bacitracin rapid

antigen tests

Hygiene practices

Penicillin cephalexin in

penicillin-allergic

Generally more severe than viral

pharyngitis

Viruses All forms of contact ndash

Goal is to rule out S pyogenes further diagnosis usually

not performed

Hygiene practices

Symptom relief only

Hoarseness frequently

accompanies viral pharyngitis

Diphtheria Corynebacterium diphtheriae

Droplet contact direct contact or indirect contact

with contaminated

Exotoxin diphtheria toxin

Tellurite mediummdashgrayblack colonies

club-shaped morphology on

Gram stain

Diphtheria toxoid vaccine (part of

DTaP)

Antitoxin plus penicillin or

erythromycin

fomitestreatment begun before definitive

identification

Pertussis (Whooping

Cough)

Bordetella pertussis Droplet contact

FHA (adhesion) pertussis toxin and tracheal

cytotoxin endotoxin

Grown on B-G charcoal or potato-

glycerol agar diagnosis can be

made on symptoms

Acellular vaccine (DTaP)

erythromycin or trimethoprim-

sulfamethoxazole for contacts

Mainly supportive erythromycin to

decrease communicability

RSV DiseaseRespiratory

syncytial virus (RSV)

Droplet and indirect contact

Syncytia formation

Direct antigen testing

Passive antibody in high-risk

children

Ribavirin in severe cases

Influenza Influenza A B and C viruses

Droplet contact direct contact some indirect

contact

Glycoprotein spikes overall

ability to change genetically

Viral culture (3ndash10 days) or rapid

antigen-based or PCR tests

Killed injected vaccine or inhaled live attenuated

vaccinemdashtaken annually

Amantadine rimantadine zanamivir or oseltamivir

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Tuberculosis

Mycobacterium tuberculosis

Vehicle (airborne)

Lipids in wall ability to

stimulate strong cell-mediated

immunity (CMI)

Rapid methods plus culture initial tests are skin testing and

chest X ray

Avoiding airborne M

tuberculosis BCG vaccine in other countries

Isoniazid rifampin and pyrazinamide 1113106 ethambutol or streptomycin for

varying lengths of time (always lengthy) if

resistant two other drugs added

to regimen

Responsible for nearly all TB except

for HIV

Mycobacterium avium complex

Vehicle (airborne) ndash Positive blood

culture

Rifabutin or azithromycin given to AIDS

patients at risk

Azithromycin or clarithromycin plus

one additional antibiotic

Suspect this in HIV-positive patients

PneumoniaStreptococcus pneumoniae

Droplet contact or endogenous

transferCapsule

Gram stain often diagnostic alpha-

hemolytic on blood agar

Pneumococcal polysaccharide

vaccine (23-valent)

Cefotaxime ceftriaxone ketek much resistance

Patient usually severely ill

Legionella species Vehicle (water droplets) ndash

Requires selective charcoal yeast extract agar

serology unreliable

ndashFluoroquinolone

azithromycin clarithromycin

Mild pneumonias in healthy people can be severe in elderly

or immunocompromised

Mycoplasma pneumoniae

Droplet contact Adhesins Rule out other etiologic agents

No vaccine no permanent immunity

Recommended not to treat in most

cases doxycycline or macrolides may

be used if

Usually mild ldquowalking pneumoniardquo

necessary

Hantavirus

Vehiclemdashairborne virus emitted from

rodents

Ability to induce inflammatory

response

Serology (IgM) PCR identification of antigen in tissue

Avoid mouse habitats and

droppingsSupportive Rapid onset high

mortality rate

SARS-associated coronavirus

Droplet direct contact

Rule out other agents serology

PCRndash Supportive Rapid onset

Histoplasma capsulatum

Vehiclemdashinhalation of

contaminated soil

Survival in phagocytes

Usually serological (rising Ab titers)

Avoid contaminated soil bat bird

droppings

Amphotericin B andor itraconazole

Many infections asymptomatic

Pneumocystis jiroveci Droplet contact ndash Immunofluorescence

Antibiotics given to AIDS patients to prevent this

Trimethoprim- sulfamethoxazole

Vast majority occur in AIDS patients

Nosocomial Pneumonia

Gram-negative and gram-positive

bacteria from upper respiratory tract or stomach

Endogenous (aspiration) Culture of lung fluids

Elevating patientrsquos head preoperative

education care of respiratory

equipment

Broad-spectrum antibiotics

Chapter 22 Infectious diseases affecting the GIT

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Dental CariesStreptococcus mutans Streptococcus sobrinus

othersDirect contact Adhesion acid

production -Oral hygiene

fluoride supplementation

Removal of diseased tooth

material

Periodontitis

Polymicrobial community including

some or all of Tannerella forsythus

Actinobacillus actinomycetemcomitans

Porphyromonas gingivalis others

Induction of inflammation Oral hygiene

Removal of plaque and calculus gum

reconstruction tetracycline

Necrotizing Ulcerative

Gingivitis and Periodontitis

Polymicrobial community (Treponema

vincentii Prevotella intermedia

Fusobacterium species)

Inflammation Oral hygiene

Debridement of damaged tissue metronidazole

clindamycin

Mumps Mumps virus (genus Paramyxovirus) Droplet contact

Spike-induced syncytium formation

Clinical fluorescent Ag tests ELISA for

Ab

MMR live attenuated

vaccineSupportive

Gastritis and Helicobacter pylori Adhesions ELISA None Antibiotics plus

Gastric Ulcers urease endoscopy

acid suppressors (clarithromycin or

metronidazole plus omeprazole

or bismuth subsalicylate)

DiseaseAcute

Diarrhea

Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

Features

Bacterial Causes

SalmonellaVehicle (food

beverage) fecal-oral

Adhesins endotoxin

Stool culture not

usually necessary

Food hygiene and

personal hygiene

Rehydration no antibiotic

for uncomplicated

disease

Usually Sometimes

Often associated

with chickens reptiles

Shigella Fecal-oral

Endotoxin enterotoxin

shiga toxins in some strains

Stool culture antigen

testing for shiga toxin

Food hygiene and

personal hygiene

TMP-SMZ rehydration Often Often Very low

ID50

Shiga-toxin- producing E coli O157H7 (EHEC)

Vehicle (food beverage) fecal-

oral

Shiga toxins proteins for attachment secretion

effacement

Stool culture antigen

testing for shiga toxin

Avoid live E coli (cook meat and

clean vegetables)

Antibiotics contraindicated supportive

measures

Often UsuallyHemolytic

uremic syndrome

Other E coli (non-shiga-toxin- producing)

Vehicle fecal-oral

Various proteins for attachment secretion

effacement heat-labile

andor heat- stable

exotoxins invasiveness

Stool culture not usually

necessary in absence of blood fever

Food and personal hygiene

Rehydration Sometimes SometimesEIEC ETEC EPEC

Campylobacter Vehicle (food water) fecal-oral

Adhesins exotoxin

induction of autoimmunity

Stool culture not usually necessary dark-field

microscopy

Food and personal hygiene

Rehydration erythromycin

in severe cases

(antibiotic resistance

rising)

Usually NoGuillain-

Barreacute syndrome

Yersinia Vehicle (food Intracellular Cold- Food and None in most Usually Occasionall Severe

water) fecal-oral indirect contact growth enrichment

stool culturepersonal hygiene

cases doxycycline or TMP-SMZ for bacteremia

y abdominal pain

Clostridium difficile

Endogenous (normal biota)

Enterotoxins A and B

Stool culture PCR

ELISA demonstration of toxins

in stool

ndash

Withdrawal of antibiotic in severe cases

metronidazole or vancomycin

SometimesNot

usually mucus

Antibiotic- associated diarrhea

Vibrio choleraeVehicle (water

and some foods) fecal-oral

Cholera toxin (CT)

Clinical diagnosis

microscopic techniques serological detection of

antitoxin

Water hygiene

Rehydration in severe

cases tetracycline

TMP-SMZ

No prominent Rice-water stools

Non-bacterial causes

Cryptosporidium Vehicle (water food) fecal-oral

Intracellular growth

Acid-fast staining ruling out bacteria

Water treatment proper food

handling

None paromomycin

used sometimes

Often Not usually

Resistant to chlorine disinfectio

n

Rotavirus Fecal-oral vehicle fomite ndash Usually not

performedOral live

virus vaccine Rehydration Often No Severe in babies

Other Viruses Fecal-oral vehicle - Usually not performed Hygiene Rehydration Sometimes No

Acute Diarrhea

with Vomiting

(Food Poisoning)

Staphylococcus aureus exotoxin

Vehicle (food)

Heat-stable exotoxin

Usually based on

epidemiological evidence

Proper food handling None Not Usually No

Suspect in foods with high salt or

sugar content

Bacillus cereusHeat-stable toxin heat-labile toxin

Microscopic analysis of

food or stool

Two forms emetic and diarrheal

Clostridium perfringens

Heat-labile toxin

Detection of toxin in stool

Acute abdominal

pain

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

FeaturesChronic Diarrhea Enteroaggregativ

e E coli (EAEC)Vehicle (food

water) fecal-oral

Difficult to distinguish

from other E coli

None or ciprofloxacin No

Sometimes mucus

also

Chronic in the

malnourished

Cyclospora cayetanensis

Fecal-oral vehicle Invasiveness Stool examination

PCR

Washing cooking

food personal hygiene

TMP-SMZ Usually No ndash

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

DNA Viruses Chickenpox smallpox fifth disease roseola warts molluscum contagiosum keratitis

RNA Viruses Measles rubellaFungi Ringworm superficial mycosisProtozoa LeishmaniasisHelminths River blindness

Chapter 19 Infectious Diseases Affecting the Nervous System

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

FeaturesMeningitis

Neisseria meningitidis Droplet contact

Capsule endotoxin IgA

protease

Gram stain culture of CSF

blood rapid antigenic tests

Conjugated vaccine

rifampin or tetracycline

used to protect contacts

Penicillin G orCefotaxime

Petechiae meningo- coccemia

Streptococcus pneumoniae Droplet contact

Capsule induction of apoptosis

hemolysin and hydrogen peroxide

production

Gram stain culture of CSF

Two vaccines Prevnar

(children) and Pneumovax

(adults)

Cefotaxime check for

resistance (add vancomycin in

that case)

Serious acute most common meningitis in

adults

Haemophilus influenzae Droplet contact Capsule

Culture on chocolate agar Hib vaccine Cefotaxime

Serious acute less common since

vaccine became available

Listeria monocytogenes Vehicle (food) Intracellular

growth

Cold enrichment

rapid methods

Cooking food avoiding

unpasteurized dairy products

Ampicillin trimethoprim- sulfamethox-

azole

Asymptomatic in healthy adults

meningitisin neonates elderly

and immuno- compromised

Cryptococcus neoformans

Vehicle (air dust soil)

Capsule melanin

production

Negative staining

biochemical tests DNA

probes

naAmphotericin B and fluconazole

Acute or chronic most common in AIDS

patients

Coccidioides immitis

Vehicle (air dust soil)

Granuloma (spherule) formation

Identification of spherules

cultivation on Sabouraudrsquos

agar

Avoiding airborne spores

Amphotericin B or oral or IV itraconazole

Almost exlusively in endemic regions

Viruses Droplet contact Lytic infection Initially absence na Usually none Generally milder than

of host cells

of bacteriafungi

protozoa followed by viral

culture or antigen tests

unless specific virus identified

and specific antiviral exists)

bacterial or fungal

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Neonatal Meningitis

Streptococcus agalactiae Vertical (during

birth) Capsule

Culture motherrsquos genital tract on blood agar CSF

culture of neonate

Culture and treatment of

mother

Penicillin G plus aminoglycosides

Most common positive culture of mother confirms

diagnosis

Escherichia coli strain K1 Vertical (during

birth) ndash CSF Gram stainculture ndash Cefotaxime plus

aminoglycosideSuspected if infant is

premature

Listeria monocytogenes Vertical Intracellular

growth

Cold enrichment

rapid methods

Cooking food avoiding

unpasteurized dairy products

Ampicillin trimethoprim-

sulfamethoxazole

Suspected if infant is premature

Meningo-encephalitis

Primary Amoebic Meningoencephaliti

sNaegleria fowleri

Vehicle (exposure while

swimming in water)

InvasivenessExamination of

CSF brain imaging

Avoid warm fresh water

Amphotericin B mostly

ineffective

Granulomatous Amoebic

Meningoencephalitis

Acanthamoeba

Direct contact InvasivenessExamination of

CSF brain imaging

ndash

Surgical excision of granulomas Ketoconazole

may help

Meningitis Arboviruses (viruses causing WEE EEE

California encephalitis SLE

West Nile encephalitis)

Vector (arthropod

bites)

Attachment fusion invasion

capabilities

History rapid serological tests

Insect control vaccines for WEE and EEE

available

None History of exposure to insect important

Herpes simplex 1 or 2

Vertical or reactivation of latent infection

ndash

Clinical presentation PCR Ab tests growth of virus in cell culture

Maternal screening for

HSVAcyclovir

In infants disseminated disease present rare between

30 and 50 years

JC virus Ubiquitous ndashPCR of

cerebrospinal fluid

None Zidovudine or other antivirals

In severely immunocompromised

especially AIDSImmunologic

reaction to other viral infections

Sequelae of measles other viral infections

and occasionally

ndash History of viral infection or vaccination

ndash Steroids anti-inflammatory

agents

History of virusvaccine

exposure critical

vaccination

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing Features

Subacute Encephalitis

Toxoplasma gondii Vehicle (meat) or fecal-oral

Intracellular growth

Serological detection of IgM

Personal hygiene food

hygiene

Pyrimethamine andor

sulfadiazine

Subacute slower development of disease

Subacute sclerosing panencephalitis

Persistence of measles virus

Cell fusion evasion of immune system

EEGs None None History of measles

Prions

CJD= directparenteral

contact with infected tissue

or inherited vCJD= vehicle

(meat parenteral)

Avoidance of host immune

responseBiopsy Avoiding tissue None Long incubation period fast

progression once it begins

Rabies Rabies virusParenteral (bite trauma) droplet

contact

Envelope glycoprotein

RT-PCR of saliva Ab detection of serum or CSF

skin biopsy

HDCVmdashinactivated

vaccine

Postexposure passive and

active immunization

na

Poliomyelitis Poliovirus Fecal-oral vehicle

Attachment mechanisms

Viral culture serology

Live attenuated (developing

world) or inactivated

vaccine (developed

world)

None palliative supportive

Tetanus Clostridium tetani Parenteral direct contact

Tetanospasm exotoxin Symptomatic Tetanus toxoid

immunization

Combination of passive antitoxin

and tetanus toxoid active

immunization supportive

na

Botulism Clostridium botulinum

Vehicle (food-borne toxin

airborne organism) direct contact (wound)

parenteral (injection)

Botulinum exotoxin

Culture of organism

demonstration of toxin

Food hygiene toxoid

immunization available for laboratory

professionals

Antitoxin supportive care na

African Sleeping Sickness

Trypanosoma brucei subspecies

gambiense or rhodesiense

Vector verticalImmune

evasion by antigen shifting

Microscopic examination of

blood CSFVector control

Suramin or pentamidine

(early) melarsoprol

(late)

Chapter 20 Infectious Diseases Affecting the Cardiovascular and lymphatic systems

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Acute Endocarditis

Staphylococcus aureus Parenteral Attachment Blood culture Aseptic surgery

injections

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Acute onset high fatality rate

Subacute Endocarditis

Alpha-hemolytic streptococci

Endogenous transfer of

normal biota to bloodstream

Attachment Blood culture

Prophylactic antibiotics before

invasive procedures

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Slower onset

Septicemia Bacteria or fungiParenteral

endogenous transfer

Cell wall or membrane

componentsBlood culture -

Broad-spectrum antibiotic until

identification and susceptibilities

tested

Plague Yersinia pestis

Vector biological also droplet contact

(pneumonic) and direct contact

with body fluids

Capsule Yop system

plasminogen activator

Culture or Gram stain of blood or bubo aspirate

Flea and or animal control

vaccine available for high-risk individuals

Streptomycin or gentamicin

Tularemia Francisella tularensis

Vector biological also direct contact

with body fluids from infected

animal airborne

Intracellular growth

Culture dangerous to lab workers and not reliable serology most often used

Live attenuated vaccine for high-risk individuals

Gentamicin or streptomycin

Lyme Disease Borrelia burgdorferi Vector biological Antigenic shifting adhesins

ELISA for Ab PCR Tick avoidance

Doxycycline andor amoxicillin (3ndash4

weeks) also cephalosporins and

penicillin

Infectious Mononucleosis

Epstein-Barr virus (EBV)

Direct indirect contact

parenteral

Latency ability to incorporate into

host DNA

Differential blood count Monospot

test for heterophile antibody

specific ELISA

ndash Supportive Most common in teens

Cytomegalovirus (CMV)

Direct indirect contact

parenteral vertical

Latency ability to fuse cells

Virus isolation and growth ELISA or PCR

tests

Vaccine in trials

Only for immunosuppressed

patients not usually for

mononucleosis

More common in adults dangerous to

fetus

Hemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Yellow fever Yellow fever virus Biological vector Disruption of clotting factors ELISA PCR Live attenuated

vaccine available Supportive Accompanied by jaundice

Dengue Fever Dengue fever virus Biological vector Disruption of clotting factors Rise in IgM titers

Live attenuated vaccine being

testedSupportive

ldquoBreakbone feverrdquomdashso named due to

severe pain

Ebola andor Marburg

Ebola virus Marburg virus

Direct contact body fluids

Disruption of clotting factors

PCR viral culture (conducted at

CDC)ndash Supportive

Massive hemorrhage rash

sometimes present

Lassa Fever Lassa fever virus

Droplet contact (aerosolized

rodent excretions)

direct contact with infected

fluids

Disruption of clotting factors ELISA Avoiding rats

safe food storage RibavirinChest pain

deafness as long-term sequelae

Nonhemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Brucellosis Brucella abortus or B suis

Direct contact airborne

parenteral (needlesticks)

Intracellular growth

avoidance of destruction by

phagocytes

Gram stain of biopsy material

Animal control pasteurization of

milk

Doxycycline plus (gentamicin or streptomycin)

Undulating fever muscle aches

Q fever Coxiella burnetii Airborne direct contact

Endosporelike structure

Serological tests for antibody

Vaccine for high-risk population Doxycycline

Airborne route of transmission

variable disease presentation

Cat-Scratch Disease Bartonella henselae food-borne Endotoxin

Biopsy of lymph nodes plus Gram staining ELISA (performed by

CDC)

Clean wound sites Azithromycin

History of cat bite or scratch fever not

always present

Trench Fever Bartonella quintana Parenteral (cat scratch or bite) Endotoxin

ELISA (performed by

CDC)Avoid lice Doxycycline or

erythromycin

Endocarditis common 5-day

fever

Ehrlichioses Ehrlichia species Biological vector (lice) - PCR indirect

antibody test Avoid lice Doxycycline Seasonal occurrence (AprilndashOct)

Rocky Mountain

Spotted FeverRickettsia rickettsii Biological vector

(tick)

Induces apoptosis in cells

lining blood vessels

Fluorescent antibody PCR Avoid lice Doxycycline

Most common in east and southeast

United States

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

MalariaPlasmodium

falciparum P vivax P ovale P malariae

Biological vector (mosquito)

vertical

Multiple life stages multiple antigenic types

ability to scavenge

glucose GPI cytoadherence

Blood smear serological methods

Mosquito control use of bed nets no vaccine yet

available prophylactic antiprotozoal

agents

Chloroquine mefloquine artemisinin

Fansidar quinine or proguanil

Anthrax Bacillus anthracis

Vehicle (air soil) indirect contact (animal hides) vehicle (food)

Triple exotoxin capsule

Culture direct fluorescent

antibody tests

Vaccine for high-risk population postexposure

antibiotic prophylaxis

Doxycycline ciprofloxacin

penicillin

HIV Infection and AIDS

Human immunodeficiency

virus 1 or 2

Direct contact (sexual)

parenteral (blood-borne)

vertical (perinatal and via breast

milk)

Attachment syncytia

formation reverse

transcriptase high mutation

rate

Initial screening for antibody followed by

Western blot confirmation of

antibody

Avoidance of contact with infected sex

partner contaminated blood breast

milk

HAART (reverse transcriptase inhibitors plus

protease inhibitors) Fuzeon nonnucleoside RT

inhibitors

Adult T-Cell Leukemia HTLV-I

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Hairy-Cell Leukemia (Possibly) HTLV-II

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Chapter 21 Infectious disease affecting the respiratory system

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Rhinitis Approximately 200 viruses

Indirect contact droplet contact

Attachment proteins most

symptoms induced by host

response

Not necessary Hygiene practices For symptoms only

Sinusitis Various bacteria often mixed

infection

Endogenous (opportunism)

Culture not usually

performed diagnosis based

Broad-spectrum antibiotics

Much more common than fungal

on clinical presentation occasionally X rays or other

imaging technique used

Various fungi

Introduction by trauma or

opportunisticOvergrowrth

Same

Physical removal of fungus in severe cases antifungals

used

Suspect in immunocompromised

patients

Otitis Media

Streptococcus pneumoniae

Endogenous (may follow

upper respiratory tract infection by S pneumoniae or

other microorganisms)

Capsule hemolysin

Usually relies on clinical

symptoms and failure to resolve within 72 hours

Pneumococcal conjugate vaccine

(heptavalent)

Wait for resolution if needed

amoxicillin (are high rates of resistance) or amoxicillin 1113106

clavalanate or cefuroxine

ndash

Haemophilus influenzae

Endogenous (follows upper

respiratory tract infection)

Capsule fimbriae Same Hib vaccine Same as for S pneumoniae ndash

Other bacteria Endogenous ndash Same None

Wait for resolution if needed a broad-spectrum antibiotic

(azithromycin) might be used in

absence of etiologic diagnosis

Suspect if fully vaccinated against

other two

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Pharyngitis

Streptococcus pyogenes

Droplet or direct contact

LTA M protein hyaluronic acid

capsule SLS and SLO

superantigens

Beta-hemolytic on blood agar sensitive to bacitracin rapid

antigen tests

Hygiene practices

Penicillin cephalexin in

penicillin-allergic

Generally more severe than viral

pharyngitis

Viruses All forms of contact ndash

Goal is to rule out S pyogenes further diagnosis usually

not performed

Hygiene practices

Symptom relief only

Hoarseness frequently

accompanies viral pharyngitis

Diphtheria Corynebacterium diphtheriae

Droplet contact direct contact or indirect contact

with contaminated

Exotoxin diphtheria toxin

Tellurite mediummdashgrayblack colonies

club-shaped morphology on

Gram stain

Diphtheria toxoid vaccine (part of

DTaP)

Antitoxin plus penicillin or

erythromycin

fomitestreatment begun before definitive

identification

Pertussis (Whooping

Cough)

Bordetella pertussis Droplet contact

FHA (adhesion) pertussis toxin and tracheal

cytotoxin endotoxin

Grown on B-G charcoal or potato-

glycerol agar diagnosis can be

made on symptoms

Acellular vaccine (DTaP)

erythromycin or trimethoprim-

sulfamethoxazole for contacts

Mainly supportive erythromycin to

decrease communicability

RSV DiseaseRespiratory

syncytial virus (RSV)

Droplet and indirect contact

Syncytia formation

Direct antigen testing

Passive antibody in high-risk

children

Ribavirin in severe cases

Influenza Influenza A B and C viruses

Droplet contact direct contact some indirect

contact

Glycoprotein spikes overall

ability to change genetically

Viral culture (3ndash10 days) or rapid

antigen-based or PCR tests

Killed injected vaccine or inhaled live attenuated

vaccinemdashtaken annually

Amantadine rimantadine zanamivir or oseltamivir

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Tuberculosis

Mycobacterium tuberculosis

Vehicle (airborne)

Lipids in wall ability to

stimulate strong cell-mediated

immunity (CMI)

Rapid methods plus culture initial tests are skin testing and

chest X ray

Avoiding airborne M

tuberculosis BCG vaccine in other countries

Isoniazid rifampin and pyrazinamide 1113106 ethambutol or streptomycin for

varying lengths of time (always lengthy) if

resistant two other drugs added

to regimen

Responsible for nearly all TB except

for HIV

Mycobacterium avium complex

Vehicle (airborne) ndash Positive blood

culture

Rifabutin or azithromycin given to AIDS

patients at risk

Azithromycin or clarithromycin plus

one additional antibiotic

Suspect this in HIV-positive patients

PneumoniaStreptococcus pneumoniae

Droplet contact or endogenous

transferCapsule

Gram stain often diagnostic alpha-

hemolytic on blood agar

Pneumococcal polysaccharide

vaccine (23-valent)

Cefotaxime ceftriaxone ketek much resistance

Patient usually severely ill

Legionella species Vehicle (water droplets) ndash

Requires selective charcoal yeast extract agar

serology unreliable

ndashFluoroquinolone

azithromycin clarithromycin

Mild pneumonias in healthy people can be severe in elderly

or immunocompromised

Mycoplasma pneumoniae

Droplet contact Adhesins Rule out other etiologic agents

No vaccine no permanent immunity

Recommended not to treat in most

cases doxycycline or macrolides may

be used if

Usually mild ldquowalking pneumoniardquo

necessary

Hantavirus

Vehiclemdashairborne virus emitted from

rodents

Ability to induce inflammatory

response

Serology (IgM) PCR identification of antigen in tissue

Avoid mouse habitats and

droppingsSupportive Rapid onset high

mortality rate

SARS-associated coronavirus

Droplet direct contact

Rule out other agents serology

PCRndash Supportive Rapid onset

Histoplasma capsulatum

Vehiclemdashinhalation of

contaminated soil

Survival in phagocytes

Usually serological (rising Ab titers)

Avoid contaminated soil bat bird

droppings

Amphotericin B andor itraconazole

Many infections asymptomatic

Pneumocystis jiroveci Droplet contact ndash Immunofluorescence

Antibiotics given to AIDS patients to prevent this

Trimethoprim- sulfamethoxazole

Vast majority occur in AIDS patients

Nosocomial Pneumonia

Gram-negative and gram-positive

bacteria from upper respiratory tract or stomach

Endogenous (aspiration) Culture of lung fluids

Elevating patientrsquos head preoperative

education care of respiratory

equipment

Broad-spectrum antibiotics

Chapter 22 Infectious diseases affecting the GIT

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Dental CariesStreptococcus mutans Streptococcus sobrinus

othersDirect contact Adhesion acid

production -Oral hygiene

fluoride supplementation

Removal of diseased tooth

material

Periodontitis

Polymicrobial community including

some or all of Tannerella forsythus

Actinobacillus actinomycetemcomitans

Porphyromonas gingivalis others

Induction of inflammation Oral hygiene

Removal of plaque and calculus gum

reconstruction tetracycline

Necrotizing Ulcerative

Gingivitis and Periodontitis

Polymicrobial community (Treponema

vincentii Prevotella intermedia

Fusobacterium species)

Inflammation Oral hygiene

Debridement of damaged tissue metronidazole

clindamycin

Mumps Mumps virus (genus Paramyxovirus) Droplet contact

Spike-induced syncytium formation

Clinical fluorescent Ag tests ELISA for

Ab

MMR live attenuated

vaccineSupportive

Gastritis and Helicobacter pylori Adhesions ELISA None Antibiotics plus

Gastric Ulcers urease endoscopy

acid suppressors (clarithromycin or

metronidazole plus omeprazole

or bismuth subsalicylate)

DiseaseAcute

Diarrhea

Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

Features

Bacterial Causes

SalmonellaVehicle (food

beverage) fecal-oral

Adhesins endotoxin

Stool culture not

usually necessary

Food hygiene and

personal hygiene

Rehydration no antibiotic

for uncomplicated

disease

Usually Sometimes

Often associated

with chickens reptiles

Shigella Fecal-oral

Endotoxin enterotoxin

shiga toxins in some strains

Stool culture antigen

testing for shiga toxin

Food hygiene and

personal hygiene

TMP-SMZ rehydration Often Often Very low

ID50

Shiga-toxin- producing E coli O157H7 (EHEC)

Vehicle (food beverage) fecal-

oral

Shiga toxins proteins for attachment secretion

effacement

Stool culture antigen

testing for shiga toxin

Avoid live E coli (cook meat and

clean vegetables)

Antibiotics contraindicated supportive

measures

Often UsuallyHemolytic

uremic syndrome

Other E coli (non-shiga-toxin- producing)

Vehicle fecal-oral

Various proteins for attachment secretion

effacement heat-labile

andor heat- stable

exotoxins invasiveness

Stool culture not usually

necessary in absence of blood fever

Food and personal hygiene

Rehydration Sometimes SometimesEIEC ETEC EPEC

Campylobacter Vehicle (food water) fecal-oral

Adhesins exotoxin

induction of autoimmunity

Stool culture not usually necessary dark-field

microscopy

Food and personal hygiene

Rehydration erythromycin

in severe cases

(antibiotic resistance

rising)

Usually NoGuillain-

Barreacute syndrome

Yersinia Vehicle (food Intracellular Cold- Food and None in most Usually Occasionall Severe

water) fecal-oral indirect contact growth enrichment

stool culturepersonal hygiene

cases doxycycline or TMP-SMZ for bacteremia

y abdominal pain

Clostridium difficile

Endogenous (normal biota)

Enterotoxins A and B

Stool culture PCR

ELISA demonstration of toxins

in stool

ndash

Withdrawal of antibiotic in severe cases

metronidazole or vancomycin

SometimesNot

usually mucus

Antibiotic- associated diarrhea

Vibrio choleraeVehicle (water

and some foods) fecal-oral

Cholera toxin (CT)

Clinical diagnosis

microscopic techniques serological detection of

antitoxin

Water hygiene

Rehydration in severe

cases tetracycline

TMP-SMZ

No prominent Rice-water stools

Non-bacterial causes

Cryptosporidium Vehicle (water food) fecal-oral

Intracellular growth

Acid-fast staining ruling out bacteria

Water treatment proper food

handling

None paromomycin

used sometimes

Often Not usually

Resistant to chlorine disinfectio

n

Rotavirus Fecal-oral vehicle fomite ndash Usually not

performedOral live

virus vaccine Rehydration Often No Severe in babies

Other Viruses Fecal-oral vehicle - Usually not performed Hygiene Rehydration Sometimes No

Acute Diarrhea

with Vomiting

(Food Poisoning)

Staphylococcus aureus exotoxin

Vehicle (food)

Heat-stable exotoxin

Usually based on

epidemiological evidence

Proper food handling None Not Usually No

Suspect in foods with high salt or

sugar content

Bacillus cereusHeat-stable toxin heat-labile toxin

Microscopic analysis of

food or stool

Two forms emetic and diarrheal

Clostridium perfringens

Heat-labile toxin

Detection of toxin in stool

Acute abdominal

pain

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

FeaturesChronic Diarrhea Enteroaggregativ

e E coli (EAEC)Vehicle (food

water) fecal-oral

Difficult to distinguish

from other E coli

None or ciprofloxacin No

Sometimes mucus

also

Chronic in the

malnourished

Cyclospora cayetanensis

Fecal-oral vehicle Invasiveness Stool examination

PCR

Washing cooking

food personal hygiene

TMP-SMZ Usually No ndash

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

of host cells

of bacteriafungi

protozoa followed by viral

culture or antigen tests

unless specific virus identified

and specific antiviral exists)

bacterial or fungal

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Neonatal Meningitis

Streptococcus agalactiae Vertical (during

birth) Capsule

Culture motherrsquos genital tract on blood agar CSF

culture of neonate

Culture and treatment of

mother

Penicillin G plus aminoglycosides

Most common positive culture of mother confirms

diagnosis

Escherichia coli strain K1 Vertical (during

birth) ndash CSF Gram stainculture ndash Cefotaxime plus

aminoglycosideSuspected if infant is

premature

Listeria monocytogenes Vertical Intracellular

growth

Cold enrichment

rapid methods

Cooking food avoiding

unpasteurized dairy products

Ampicillin trimethoprim-

sulfamethoxazole

Suspected if infant is premature

Meningo-encephalitis

Primary Amoebic Meningoencephaliti

sNaegleria fowleri

Vehicle (exposure while

swimming in water)

InvasivenessExamination of

CSF brain imaging

Avoid warm fresh water

Amphotericin B mostly

ineffective

Granulomatous Amoebic

Meningoencephalitis

Acanthamoeba

Direct contact InvasivenessExamination of

CSF brain imaging

ndash

Surgical excision of granulomas Ketoconazole

may help

Meningitis Arboviruses (viruses causing WEE EEE

California encephalitis SLE

West Nile encephalitis)

Vector (arthropod

bites)

Attachment fusion invasion

capabilities

History rapid serological tests

Insect control vaccines for WEE and EEE

available

None History of exposure to insect important

Herpes simplex 1 or 2

Vertical or reactivation of latent infection

ndash

Clinical presentation PCR Ab tests growth of virus in cell culture

Maternal screening for

HSVAcyclovir

In infants disseminated disease present rare between

30 and 50 years

JC virus Ubiquitous ndashPCR of

cerebrospinal fluid

None Zidovudine or other antivirals

In severely immunocompromised

especially AIDSImmunologic

reaction to other viral infections

Sequelae of measles other viral infections

and occasionally

ndash History of viral infection or vaccination

ndash Steroids anti-inflammatory

agents

History of virusvaccine

exposure critical

vaccination

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing Features

Subacute Encephalitis

Toxoplasma gondii Vehicle (meat) or fecal-oral

Intracellular growth

Serological detection of IgM

Personal hygiene food

hygiene

Pyrimethamine andor

sulfadiazine

Subacute slower development of disease

Subacute sclerosing panencephalitis

Persistence of measles virus

Cell fusion evasion of immune system

EEGs None None History of measles

Prions

CJD= directparenteral

contact with infected tissue

or inherited vCJD= vehicle

(meat parenteral)

Avoidance of host immune

responseBiopsy Avoiding tissue None Long incubation period fast

progression once it begins

Rabies Rabies virusParenteral (bite trauma) droplet

contact

Envelope glycoprotein

RT-PCR of saliva Ab detection of serum or CSF

skin biopsy

HDCVmdashinactivated

vaccine

Postexposure passive and

active immunization

na

Poliomyelitis Poliovirus Fecal-oral vehicle

Attachment mechanisms

Viral culture serology

Live attenuated (developing

world) or inactivated

vaccine (developed

world)

None palliative supportive

Tetanus Clostridium tetani Parenteral direct contact

Tetanospasm exotoxin Symptomatic Tetanus toxoid

immunization

Combination of passive antitoxin

and tetanus toxoid active

immunization supportive

na

Botulism Clostridium botulinum

Vehicle (food-borne toxin

airborne organism) direct contact (wound)

parenteral (injection)

Botulinum exotoxin

Culture of organism

demonstration of toxin

Food hygiene toxoid

immunization available for laboratory

professionals

Antitoxin supportive care na

African Sleeping Sickness

Trypanosoma brucei subspecies

gambiense or rhodesiense

Vector verticalImmune

evasion by antigen shifting

Microscopic examination of

blood CSFVector control

Suramin or pentamidine

(early) melarsoprol

(late)

Chapter 20 Infectious Diseases Affecting the Cardiovascular and lymphatic systems

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Acute Endocarditis

Staphylococcus aureus Parenteral Attachment Blood culture Aseptic surgery

injections

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Acute onset high fatality rate

Subacute Endocarditis

Alpha-hemolytic streptococci

Endogenous transfer of

normal biota to bloodstream

Attachment Blood culture

Prophylactic antibiotics before

invasive procedures

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Slower onset

Septicemia Bacteria or fungiParenteral

endogenous transfer

Cell wall or membrane

componentsBlood culture -

Broad-spectrum antibiotic until

identification and susceptibilities

tested

Plague Yersinia pestis

Vector biological also droplet contact

(pneumonic) and direct contact

with body fluids

Capsule Yop system

plasminogen activator

Culture or Gram stain of blood or bubo aspirate

Flea and or animal control

vaccine available for high-risk individuals

Streptomycin or gentamicin

Tularemia Francisella tularensis

Vector biological also direct contact

with body fluids from infected

animal airborne

Intracellular growth

Culture dangerous to lab workers and not reliable serology most often used

Live attenuated vaccine for high-risk individuals

Gentamicin or streptomycin

Lyme Disease Borrelia burgdorferi Vector biological Antigenic shifting adhesins

ELISA for Ab PCR Tick avoidance

Doxycycline andor amoxicillin (3ndash4

weeks) also cephalosporins and

penicillin

Infectious Mononucleosis

Epstein-Barr virus (EBV)

Direct indirect contact

parenteral

Latency ability to incorporate into

host DNA

Differential blood count Monospot

test for heterophile antibody

specific ELISA

ndash Supportive Most common in teens

Cytomegalovirus (CMV)

Direct indirect contact

parenteral vertical

Latency ability to fuse cells

Virus isolation and growth ELISA or PCR

tests

Vaccine in trials

Only for immunosuppressed

patients not usually for

mononucleosis

More common in adults dangerous to

fetus

Hemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Yellow fever Yellow fever virus Biological vector Disruption of clotting factors ELISA PCR Live attenuated

vaccine available Supportive Accompanied by jaundice

Dengue Fever Dengue fever virus Biological vector Disruption of clotting factors Rise in IgM titers

Live attenuated vaccine being

testedSupportive

ldquoBreakbone feverrdquomdashso named due to

severe pain

Ebola andor Marburg

Ebola virus Marburg virus

Direct contact body fluids

Disruption of clotting factors

PCR viral culture (conducted at

CDC)ndash Supportive

Massive hemorrhage rash

sometimes present

Lassa Fever Lassa fever virus

Droplet contact (aerosolized

rodent excretions)

direct contact with infected

fluids

Disruption of clotting factors ELISA Avoiding rats

safe food storage RibavirinChest pain

deafness as long-term sequelae

Nonhemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Brucellosis Brucella abortus or B suis

Direct contact airborne

parenteral (needlesticks)

Intracellular growth

avoidance of destruction by

phagocytes

Gram stain of biopsy material

Animal control pasteurization of

milk

Doxycycline plus (gentamicin or streptomycin)

Undulating fever muscle aches

Q fever Coxiella burnetii Airborne direct contact

Endosporelike structure

Serological tests for antibody

Vaccine for high-risk population Doxycycline

Airborne route of transmission

variable disease presentation

Cat-Scratch Disease Bartonella henselae food-borne Endotoxin

Biopsy of lymph nodes plus Gram staining ELISA (performed by

CDC)

Clean wound sites Azithromycin

History of cat bite or scratch fever not

always present

Trench Fever Bartonella quintana Parenteral (cat scratch or bite) Endotoxin

ELISA (performed by

CDC)Avoid lice Doxycycline or

erythromycin

Endocarditis common 5-day

fever

Ehrlichioses Ehrlichia species Biological vector (lice) - PCR indirect

antibody test Avoid lice Doxycycline Seasonal occurrence (AprilndashOct)

Rocky Mountain

Spotted FeverRickettsia rickettsii Biological vector

(tick)

Induces apoptosis in cells

lining blood vessels

Fluorescent antibody PCR Avoid lice Doxycycline

Most common in east and southeast

United States

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

MalariaPlasmodium

falciparum P vivax P ovale P malariae

Biological vector (mosquito)

vertical

Multiple life stages multiple antigenic types

ability to scavenge

glucose GPI cytoadherence

Blood smear serological methods

Mosquito control use of bed nets no vaccine yet

available prophylactic antiprotozoal

agents

Chloroquine mefloquine artemisinin

Fansidar quinine or proguanil

Anthrax Bacillus anthracis

Vehicle (air soil) indirect contact (animal hides) vehicle (food)

Triple exotoxin capsule

Culture direct fluorescent

antibody tests

Vaccine for high-risk population postexposure

antibiotic prophylaxis

Doxycycline ciprofloxacin

penicillin

HIV Infection and AIDS

Human immunodeficiency

virus 1 or 2

Direct contact (sexual)

parenteral (blood-borne)

vertical (perinatal and via breast

milk)

Attachment syncytia

formation reverse

transcriptase high mutation

rate

Initial screening for antibody followed by

Western blot confirmation of

antibody

Avoidance of contact with infected sex

partner contaminated blood breast

milk

HAART (reverse transcriptase inhibitors plus

protease inhibitors) Fuzeon nonnucleoside RT

inhibitors

Adult T-Cell Leukemia HTLV-I

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Hairy-Cell Leukemia (Possibly) HTLV-II

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Chapter 21 Infectious disease affecting the respiratory system

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Rhinitis Approximately 200 viruses

Indirect contact droplet contact

Attachment proteins most

symptoms induced by host

response

Not necessary Hygiene practices For symptoms only

Sinusitis Various bacteria often mixed

infection

Endogenous (opportunism)

Culture not usually

performed diagnosis based

Broad-spectrum antibiotics

Much more common than fungal

on clinical presentation occasionally X rays or other

imaging technique used

Various fungi

Introduction by trauma or

opportunisticOvergrowrth

Same

Physical removal of fungus in severe cases antifungals

used

Suspect in immunocompromised

patients

Otitis Media

Streptococcus pneumoniae

Endogenous (may follow

upper respiratory tract infection by S pneumoniae or

other microorganisms)

Capsule hemolysin

Usually relies on clinical

symptoms and failure to resolve within 72 hours

Pneumococcal conjugate vaccine

(heptavalent)

Wait for resolution if needed

amoxicillin (are high rates of resistance) or amoxicillin 1113106

clavalanate or cefuroxine

ndash

Haemophilus influenzae

Endogenous (follows upper

respiratory tract infection)

Capsule fimbriae Same Hib vaccine Same as for S pneumoniae ndash

Other bacteria Endogenous ndash Same None

Wait for resolution if needed a broad-spectrum antibiotic

(azithromycin) might be used in

absence of etiologic diagnosis

Suspect if fully vaccinated against

other two

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Pharyngitis

Streptococcus pyogenes

Droplet or direct contact

LTA M protein hyaluronic acid

capsule SLS and SLO

superantigens

Beta-hemolytic on blood agar sensitive to bacitracin rapid

antigen tests

Hygiene practices

Penicillin cephalexin in

penicillin-allergic

Generally more severe than viral

pharyngitis

Viruses All forms of contact ndash

Goal is to rule out S pyogenes further diagnosis usually

not performed

Hygiene practices

Symptom relief only

Hoarseness frequently

accompanies viral pharyngitis

Diphtheria Corynebacterium diphtheriae

Droplet contact direct contact or indirect contact

with contaminated

Exotoxin diphtheria toxin

Tellurite mediummdashgrayblack colonies

club-shaped morphology on

Gram stain

Diphtheria toxoid vaccine (part of

DTaP)

Antitoxin plus penicillin or

erythromycin

fomitestreatment begun before definitive

identification

Pertussis (Whooping

Cough)

Bordetella pertussis Droplet contact

FHA (adhesion) pertussis toxin and tracheal

cytotoxin endotoxin

Grown on B-G charcoal or potato-

glycerol agar diagnosis can be

made on symptoms

Acellular vaccine (DTaP)

erythromycin or trimethoprim-

sulfamethoxazole for contacts

Mainly supportive erythromycin to

decrease communicability

RSV DiseaseRespiratory

syncytial virus (RSV)

Droplet and indirect contact

Syncytia formation

Direct antigen testing

Passive antibody in high-risk

children

Ribavirin in severe cases

Influenza Influenza A B and C viruses

Droplet contact direct contact some indirect

contact

Glycoprotein spikes overall

ability to change genetically

Viral culture (3ndash10 days) or rapid

antigen-based or PCR tests

Killed injected vaccine or inhaled live attenuated

vaccinemdashtaken annually

Amantadine rimantadine zanamivir or oseltamivir

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Tuberculosis

Mycobacterium tuberculosis

Vehicle (airborne)

Lipids in wall ability to

stimulate strong cell-mediated

immunity (CMI)

Rapid methods plus culture initial tests are skin testing and

chest X ray

Avoiding airborne M

tuberculosis BCG vaccine in other countries

Isoniazid rifampin and pyrazinamide 1113106 ethambutol or streptomycin for

varying lengths of time (always lengthy) if

resistant two other drugs added

to regimen

Responsible for nearly all TB except

for HIV

Mycobacterium avium complex

Vehicle (airborne) ndash Positive blood

culture

Rifabutin or azithromycin given to AIDS

patients at risk

Azithromycin or clarithromycin plus

one additional antibiotic

Suspect this in HIV-positive patients

PneumoniaStreptococcus pneumoniae

Droplet contact or endogenous

transferCapsule

Gram stain often diagnostic alpha-

hemolytic on blood agar

Pneumococcal polysaccharide

vaccine (23-valent)

Cefotaxime ceftriaxone ketek much resistance

Patient usually severely ill

Legionella species Vehicle (water droplets) ndash

Requires selective charcoal yeast extract agar

serology unreliable

ndashFluoroquinolone

azithromycin clarithromycin

Mild pneumonias in healthy people can be severe in elderly

or immunocompromised

Mycoplasma pneumoniae

Droplet contact Adhesins Rule out other etiologic agents

No vaccine no permanent immunity

Recommended not to treat in most

cases doxycycline or macrolides may

be used if

Usually mild ldquowalking pneumoniardquo

necessary

Hantavirus

Vehiclemdashairborne virus emitted from

rodents

Ability to induce inflammatory

response

Serology (IgM) PCR identification of antigen in tissue

Avoid mouse habitats and

droppingsSupportive Rapid onset high

mortality rate

SARS-associated coronavirus

Droplet direct contact

Rule out other agents serology

PCRndash Supportive Rapid onset

Histoplasma capsulatum

Vehiclemdashinhalation of

contaminated soil

Survival in phagocytes

Usually serological (rising Ab titers)

Avoid contaminated soil bat bird

droppings

Amphotericin B andor itraconazole

Many infections asymptomatic

Pneumocystis jiroveci Droplet contact ndash Immunofluorescence

Antibiotics given to AIDS patients to prevent this

Trimethoprim- sulfamethoxazole

Vast majority occur in AIDS patients

Nosocomial Pneumonia

Gram-negative and gram-positive

bacteria from upper respiratory tract or stomach

Endogenous (aspiration) Culture of lung fluids

Elevating patientrsquos head preoperative

education care of respiratory

equipment

Broad-spectrum antibiotics

Chapter 22 Infectious diseases affecting the GIT

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Dental CariesStreptococcus mutans Streptococcus sobrinus

othersDirect contact Adhesion acid

production -Oral hygiene

fluoride supplementation

Removal of diseased tooth

material

Periodontitis

Polymicrobial community including

some or all of Tannerella forsythus

Actinobacillus actinomycetemcomitans

Porphyromonas gingivalis others

Induction of inflammation Oral hygiene

Removal of plaque and calculus gum

reconstruction tetracycline

Necrotizing Ulcerative

Gingivitis and Periodontitis

Polymicrobial community (Treponema

vincentii Prevotella intermedia

Fusobacterium species)

Inflammation Oral hygiene

Debridement of damaged tissue metronidazole

clindamycin

Mumps Mumps virus (genus Paramyxovirus) Droplet contact

Spike-induced syncytium formation

Clinical fluorescent Ag tests ELISA for

Ab

MMR live attenuated

vaccineSupportive

Gastritis and Helicobacter pylori Adhesions ELISA None Antibiotics plus

Gastric Ulcers urease endoscopy

acid suppressors (clarithromycin or

metronidazole plus omeprazole

or bismuth subsalicylate)

DiseaseAcute

Diarrhea

Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

Features

Bacterial Causes

SalmonellaVehicle (food

beverage) fecal-oral

Adhesins endotoxin

Stool culture not

usually necessary

Food hygiene and

personal hygiene

Rehydration no antibiotic

for uncomplicated

disease

Usually Sometimes

Often associated

with chickens reptiles

Shigella Fecal-oral

Endotoxin enterotoxin

shiga toxins in some strains

Stool culture antigen

testing for shiga toxin

Food hygiene and

personal hygiene

TMP-SMZ rehydration Often Often Very low

ID50

Shiga-toxin- producing E coli O157H7 (EHEC)

Vehicle (food beverage) fecal-

oral

Shiga toxins proteins for attachment secretion

effacement

Stool culture antigen

testing for shiga toxin

Avoid live E coli (cook meat and

clean vegetables)

Antibiotics contraindicated supportive

measures

Often UsuallyHemolytic

uremic syndrome

Other E coli (non-shiga-toxin- producing)

Vehicle fecal-oral

Various proteins for attachment secretion

effacement heat-labile

andor heat- stable

exotoxins invasiveness

Stool culture not usually

necessary in absence of blood fever

Food and personal hygiene

Rehydration Sometimes SometimesEIEC ETEC EPEC

Campylobacter Vehicle (food water) fecal-oral

Adhesins exotoxin

induction of autoimmunity

Stool culture not usually necessary dark-field

microscopy

Food and personal hygiene

Rehydration erythromycin

in severe cases

(antibiotic resistance

rising)

Usually NoGuillain-

Barreacute syndrome

Yersinia Vehicle (food Intracellular Cold- Food and None in most Usually Occasionall Severe

water) fecal-oral indirect contact growth enrichment

stool culturepersonal hygiene

cases doxycycline or TMP-SMZ for bacteremia

y abdominal pain

Clostridium difficile

Endogenous (normal biota)

Enterotoxins A and B

Stool culture PCR

ELISA demonstration of toxins

in stool

ndash

Withdrawal of antibiotic in severe cases

metronidazole or vancomycin

SometimesNot

usually mucus

Antibiotic- associated diarrhea

Vibrio choleraeVehicle (water

and some foods) fecal-oral

Cholera toxin (CT)

Clinical diagnosis

microscopic techniques serological detection of

antitoxin

Water hygiene

Rehydration in severe

cases tetracycline

TMP-SMZ

No prominent Rice-water stools

Non-bacterial causes

Cryptosporidium Vehicle (water food) fecal-oral

Intracellular growth

Acid-fast staining ruling out bacteria

Water treatment proper food

handling

None paromomycin

used sometimes

Often Not usually

Resistant to chlorine disinfectio

n

Rotavirus Fecal-oral vehicle fomite ndash Usually not

performedOral live

virus vaccine Rehydration Often No Severe in babies

Other Viruses Fecal-oral vehicle - Usually not performed Hygiene Rehydration Sometimes No

Acute Diarrhea

with Vomiting

(Food Poisoning)

Staphylococcus aureus exotoxin

Vehicle (food)

Heat-stable exotoxin

Usually based on

epidemiological evidence

Proper food handling None Not Usually No

Suspect in foods with high salt or

sugar content

Bacillus cereusHeat-stable toxin heat-labile toxin

Microscopic analysis of

food or stool

Two forms emetic and diarrheal

Clostridium perfringens

Heat-labile toxin

Detection of toxin in stool

Acute abdominal

pain

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

FeaturesChronic Diarrhea Enteroaggregativ

e E coli (EAEC)Vehicle (food

water) fecal-oral

Difficult to distinguish

from other E coli

None or ciprofloxacin No

Sometimes mucus

also

Chronic in the

malnourished

Cyclospora cayetanensis

Fecal-oral vehicle Invasiveness Stool examination

PCR

Washing cooking

food personal hygiene

TMP-SMZ Usually No ndash

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

vaccination

Disease Causative Organism(s)

Mode(s) of Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing Features

Subacute Encephalitis

Toxoplasma gondii Vehicle (meat) or fecal-oral

Intracellular growth

Serological detection of IgM

Personal hygiene food

hygiene

Pyrimethamine andor

sulfadiazine

Subacute slower development of disease

Subacute sclerosing panencephalitis

Persistence of measles virus

Cell fusion evasion of immune system

EEGs None None History of measles

Prions

CJD= directparenteral

contact with infected tissue

or inherited vCJD= vehicle

(meat parenteral)

Avoidance of host immune

responseBiopsy Avoiding tissue None Long incubation period fast

progression once it begins

Rabies Rabies virusParenteral (bite trauma) droplet

contact

Envelope glycoprotein

RT-PCR of saliva Ab detection of serum or CSF

skin biopsy

HDCVmdashinactivated

vaccine

Postexposure passive and

active immunization

na

Poliomyelitis Poliovirus Fecal-oral vehicle

Attachment mechanisms

Viral culture serology

Live attenuated (developing

world) or inactivated

vaccine (developed

world)

None palliative supportive

Tetanus Clostridium tetani Parenteral direct contact

Tetanospasm exotoxin Symptomatic Tetanus toxoid

immunization

Combination of passive antitoxin

and tetanus toxoid active

immunization supportive

na

Botulism Clostridium botulinum

Vehicle (food-borne toxin

airborne organism) direct contact (wound)

parenteral (injection)

Botulinum exotoxin

Culture of organism

demonstration of toxin

Food hygiene toxoid

immunization available for laboratory

professionals

Antitoxin supportive care na

African Sleeping Sickness

Trypanosoma brucei subspecies

gambiense or rhodesiense

Vector verticalImmune

evasion by antigen shifting

Microscopic examination of

blood CSFVector control

Suramin or pentamidine

(early) melarsoprol

(late)

Chapter 20 Infectious Diseases Affecting the Cardiovascular and lymphatic systems

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Acute Endocarditis

Staphylococcus aureus Parenteral Attachment Blood culture Aseptic surgery

injections

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Acute onset high fatality rate

Subacute Endocarditis

Alpha-hemolytic streptococci

Endogenous transfer of

normal biota to bloodstream

Attachment Blood culture

Prophylactic antibiotics before

invasive procedures

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Slower onset

Septicemia Bacteria or fungiParenteral

endogenous transfer

Cell wall or membrane

componentsBlood culture -

Broad-spectrum antibiotic until

identification and susceptibilities

tested

Plague Yersinia pestis

Vector biological also droplet contact

(pneumonic) and direct contact

with body fluids

Capsule Yop system

plasminogen activator

Culture or Gram stain of blood or bubo aspirate

Flea and or animal control

vaccine available for high-risk individuals

Streptomycin or gentamicin

Tularemia Francisella tularensis

Vector biological also direct contact

with body fluids from infected

animal airborne

Intracellular growth

Culture dangerous to lab workers and not reliable serology most often used

Live attenuated vaccine for high-risk individuals

Gentamicin or streptomycin

Lyme Disease Borrelia burgdorferi Vector biological Antigenic shifting adhesins

ELISA for Ab PCR Tick avoidance

Doxycycline andor amoxicillin (3ndash4

weeks) also cephalosporins and

penicillin

Infectious Mononucleosis

Epstein-Barr virus (EBV)

Direct indirect contact

parenteral

Latency ability to incorporate into

host DNA

Differential blood count Monospot

test for heterophile antibody

specific ELISA

ndash Supportive Most common in teens

Cytomegalovirus (CMV)

Direct indirect contact

parenteral vertical

Latency ability to fuse cells

Virus isolation and growth ELISA or PCR

tests

Vaccine in trials

Only for immunosuppressed

patients not usually for

mononucleosis

More common in adults dangerous to

fetus

Hemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Yellow fever Yellow fever virus Biological vector Disruption of clotting factors ELISA PCR Live attenuated

vaccine available Supportive Accompanied by jaundice

Dengue Fever Dengue fever virus Biological vector Disruption of clotting factors Rise in IgM titers

Live attenuated vaccine being

testedSupportive

ldquoBreakbone feverrdquomdashso named due to

severe pain

Ebola andor Marburg

Ebola virus Marburg virus

Direct contact body fluids

Disruption of clotting factors

PCR viral culture (conducted at

CDC)ndash Supportive

Massive hemorrhage rash

sometimes present

Lassa Fever Lassa fever virus

Droplet contact (aerosolized

rodent excretions)

direct contact with infected

fluids

Disruption of clotting factors ELISA Avoiding rats

safe food storage RibavirinChest pain

deafness as long-term sequelae

Nonhemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Brucellosis Brucella abortus or B suis

Direct contact airborne

parenteral (needlesticks)

Intracellular growth

avoidance of destruction by

phagocytes

Gram stain of biopsy material

Animal control pasteurization of

milk

Doxycycline plus (gentamicin or streptomycin)

Undulating fever muscle aches

Q fever Coxiella burnetii Airborne direct contact

Endosporelike structure

Serological tests for antibody

Vaccine for high-risk population Doxycycline

Airborne route of transmission

variable disease presentation

Cat-Scratch Disease Bartonella henselae food-borne Endotoxin

Biopsy of lymph nodes plus Gram staining ELISA (performed by

CDC)

Clean wound sites Azithromycin

History of cat bite or scratch fever not

always present

Trench Fever Bartonella quintana Parenteral (cat scratch or bite) Endotoxin

ELISA (performed by

CDC)Avoid lice Doxycycline or

erythromycin

Endocarditis common 5-day

fever

Ehrlichioses Ehrlichia species Biological vector (lice) - PCR indirect

antibody test Avoid lice Doxycycline Seasonal occurrence (AprilndashOct)

Rocky Mountain

Spotted FeverRickettsia rickettsii Biological vector

(tick)

Induces apoptosis in cells

lining blood vessels

Fluorescent antibody PCR Avoid lice Doxycycline

Most common in east and southeast

United States

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

MalariaPlasmodium

falciparum P vivax P ovale P malariae

Biological vector (mosquito)

vertical

Multiple life stages multiple antigenic types

ability to scavenge

glucose GPI cytoadherence

Blood smear serological methods

Mosquito control use of bed nets no vaccine yet

available prophylactic antiprotozoal

agents

Chloroquine mefloquine artemisinin

Fansidar quinine or proguanil

Anthrax Bacillus anthracis

Vehicle (air soil) indirect contact (animal hides) vehicle (food)

Triple exotoxin capsule

Culture direct fluorescent

antibody tests

Vaccine for high-risk population postexposure

antibiotic prophylaxis

Doxycycline ciprofloxacin

penicillin

HIV Infection and AIDS

Human immunodeficiency

virus 1 or 2

Direct contact (sexual)

parenteral (blood-borne)

vertical (perinatal and via breast

milk)

Attachment syncytia

formation reverse

transcriptase high mutation

rate

Initial screening for antibody followed by

Western blot confirmation of

antibody

Avoidance of contact with infected sex

partner contaminated blood breast

milk

HAART (reverse transcriptase inhibitors plus

protease inhibitors) Fuzeon nonnucleoside RT

inhibitors

Adult T-Cell Leukemia HTLV-I

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Hairy-Cell Leukemia (Possibly) HTLV-II

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Chapter 21 Infectious disease affecting the respiratory system

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Rhinitis Approximately 200 viruses

Indirect contact droplet contact

Attachment proteins most

symptoms induced by host

response

Not necessary Hygiene practices For symptoms only

Sinusitis Various bacteria often mixed

infection

Endogenous (opportunism)

Culture not usually

performed diagnosis based

Broad-spectrum antibiotics

Much more common than fungal

on clinical presentation occasionally X rays or other

imaging technique used

Various fungi

Introduction by trauma or

opportunisticOvergrowrth

Same

Physical removal of fungus in severe cases antifungals

used

Suspect in immunocompromised

patients

Otitis Media

Streptococcus pneumoniae

Endogenous (may follow

upper respiratory tract infection by S pneumoniae or

other microorganisms)

Capsule hemolysin

Usually relies on clinical

symptoms and failure to resolve within 72 hours

Pneumococcal conjugate vaccine

(heptavalent)

Wait for resolution if needed

amoxicillin (are high rates of resistance) or amoxicillin 1113106

clavalanate or cefuroxine

ndash

Haemophilus influenzae

Endogenous (follows upper

respiratory tract infection)

Capsule fimbriae Same Hib vaccine Same as for S pneumoniae ndash

Other bacteria Endogenous ndash Same None

Wait for resolution if needed a broad-spectrum antibiotic

(azithromycin) might be used in

absence of etiologic diagnosis

Suspect if fully vaccinated against

other two

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Pharyngitis

Streptococcus pyogenes

Droplet or direct contact

LTA M protein hyaluronic acid

capsule SLS and SLO

superantigens

Beta-hemolytic on blood agar sensitive to bacitracin rapid

antigen tests

Hygiene practices

Penicillin cephalexin in

penicillin-allergic

Generally more severe than viral

pharyngitis

Viruses All forms of contact ndash

Goal is to rule out S pyogenes further diagnosis usually

not performed

Hygiene practices

Symptom relief only

Hoarseness frequently

accompanies viral pharyngitis

Diphtheria Corynebacterium diphtheriae

Droplet contact direct contact or indirect contact

with contaminated

Exotoxin diphtheria toxin

Tellurite mediummdashgrayblack colonies

club-shaped morphology on

Gram stain

Diphtheria toxoid vaccine (part of

DTaP)

Antitoxin plus penicillin or

erythromycin

fomitestreatment begun before definitive

identification

Pertussis (Whooping

Cough)

Bordetella pertussis Droplet contact

FHA (adhesion) pertussis toxin and tracheal

cytotoxin endotoxin

Grown on B-G charcoal or potato-

glycerol agar diagnosis can be

made on symptoms

Acellular vaccine (DTaP)

erythromycin or trimethoprim-

sulfamethoxazole for contacts

Mainly supportive erythromycin to

decrease communicability

RSV DiseaseRespiratory

syncytial virus (RSV)

Droplet and indirect contact

Syncytia formation

Direct antigen testing

Passive antibody in high-risk

children

Ribavirin in severe cases

Influenza Influenza A B and C viruses

Droplet contact direct contact some indirect

contact

Glycoprotein spikes overall

ability to change genetically

Viral culture (3ndash10 days) or rapid

antigen-based or PCR tests

Killed injected vaccine or inhaled live attenuated

vaccinemdashtaken annually

Amantadine rimantadine zanamivir or oseltamivir

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Tuberculosis

Mycobacterium tuberculosis

Vehicle (airborne)

Lipids in wall ability to

stimulate strong cell-mediated

immunity (CMI)

Rapid methods plus culture initial tests are skin testing and

chest X ray

Avoiding airborne M

tuberculosis BCG vaccine in other countries

Isoniazid rifampin and pyrazinamide 1113106 ethambutol or streptomycin for

varying lengths of time (always lengthy) if

resistant two other drugs added

to regimen

Responsible for nearly all TB except

for HIV

Mycobacterium avium complex

Vehicle (airborne) ndash Positive blood

culture

Rifabutin or azithromycin given to AIDS

patients at risk

Azithromycin or clarithromycin plus

one additional antibiotic

Suspect this in HIV-positive patients

PneumoniaStreptococcus pneumoniae

Droplet contact or endogenous

transferCapsule

Gram stain often diagnostic alpha-

hemolytic on blood agar

Pneumococcal polysaccharide

vaccine (23-valent)

Cefotaxime ceftriaxone ketek much resistance

Patient usually severely ill

Legionella species Vehicle (water droplets) ndash

Requires selective charcoal yeast extract agar

serology unreliable

ndashFluoroquinolone

azithromycin clarithromycin

Mild pneumonias in healthy people can be severe in elderly

or immunocompromised

Mycoplasma pneumoniae

Droplet contact Adhesins Rule out other etiologic agents

No vaccine no permanent immunity

Recommended not to treat in most

cases doxycycline or macrolides may

be used if

Usually mild ldquowalking pneumoniardquo

necessary

Hantavirus

Vehiclemdashairborne virus emitted from

rodents

Ability to induce inflammatory

response

Serology (IgM) PCR identification of antigen in tissue

Avoid mouse habitats and

droppingsSupportive Rapid onset high

mortality rate

SARS-associated coronavirus

Droplet direct contact

Rule out other agents serology

PCRndash Supportive Rapid onset

Histoplasma capsulatum

Vehiclemdashinhalation of

contaminated soil

Survival in phagocytes

Usually serological (rising Ab titers)

Avoid contaminated soil bat bird

droppings

Amphotericin B andor itraconazole

Many infections asymptomatic

Pneumocystis jiroveci Droplet contact ndash Immunofluorescence

Antibiotics given to AIDS patients to prevent this

Trimethoprim- sulfamethoxazole

Vast majority occur in AIDS patients

Nosocomial Pneumonia

Gram-negative and gram-positive

bacteria from upper respiratory tract or stomach

Endogenous (aspiration) Culture of lung fluids

Elevating patientrsquos head preoperative

education care of respiratory

equipment

Broad-spectrum antibiotics

Chapter 22 Infectious diseases affecting the GIT

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Dental CariesStreptococcus mutans Streptococcus sobrinus

othersDirect contact Adhesion acid

production -Oral hygiene

fluoride supplementation

Removal of diseased tooth

material

Periodontitis

Polymicrobial community including

some or all of Tannerella forsythus

Actinobacillus actinomycetemcomitans

Porphyromonas gingivalis others

Induction of inflammation Oral hygiene

Removal of plaque and calculus gum

reconstruction tetracycline

Necrotizing Ulcerative

Gingivitis and Periodontitis

Polymicrobial community (Treponema

vincentii Prevotella intermedia

Fusobacterium species)

Inflammation Oral hygiene

Debridement of damaged tissue metronidazole

clindamycin

Mumps Mumps virus (genus Paramyxovirus) Droplet contact

Spike-induced syncytium formation

Clinical fluorescent Ag tests ELISA for

Ab

MMR live attenuated

vaccineSupportive

Gastritis and Helicobacter pylori Adhesions ELISA None Antibiotics plus

Gastric Ulcers urease endoscopy

acid suppressors (clarithromycin or

metronidazole plus omeprazole

or bismuth subsalicylate)

DiseaseAcute

Diarrhea

Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

Features

Bacterial Causes

SalmonellaVehicle (food

beverage) fecal-oral

Adhesins endotoxin

Stool culture not

usually necessary

Food hygiene and

personal hygiene

Rehydration no antibiotic

for uncomplicated

disease

Usually Sometimes

Often associated

with chickens reptiles

Shigella Fecal-oral

Endotoxin enterotoxin

shiga toxins in some strains

Stool culture antigen

testing for shiga toxin

Food hygiene and

personal hygiene

TMP-SMZ rehydration Often Often Very low

ID50

Shiga-toxin- producing E coli O157H7 (EHEC)

Vehicle (food beverage) fecal-

oral

Shiga toxins proteins for attachment secretion

effacement

Stool culture antigen

testing for shiga toxin

Avoid live E coli (cook meat and

clean vegetables)

Antibiotics contraindicated supportive

measures

Often UsuallyHemolytic

uremic syndrome

Other E coli (non-shiga-toxin- producing)

Vehicle fecal-oral

Various proteins for attachment secretion

effacement heat-labile

andor heat- stable

exotoxins invasiveness

Stool culture not usually

necessary in absence of blood fever

Food and personal hygiene

Rehydration Sometimes SometimesEIEC ETEC EPEC

Campylobacter Vehicle (food water) fecal-oral

Adhesins exotoxin

induction of autoimmunity

Stool culture not usually necessary dark-field

microscopy

Food and personal hygiene

Rehydration erythromycin

in severe cases

(antibiotic resistance

rising)

Usually NoGuillain-

Barreacute syndrome

Yersinia Vehicle (food Intracellular Cold- Food and None in most Usually Occasionall Severe

water) fecal-oral indirect contact growth enrichment

stool culturepersonal hygiene

cases doxycycline or TMP-SMZ for bacteremia

y abdominal pain

Clostridium difficile

Endogenous (normal biota)

Enterotoxins A and B

Stool culture PCR

ELISA demonstration of toxins

in stool

ndash

Withdrawal of antibiotic in severe cases

metronidazole or vancomycin

SometimesNot

usually mucus

Antibiotic- associated diarrhea

Vibrio choleraeVehicle (water

and some foods) fecal-oral

Cholera toxin (CT)

Clinical diagnosis

microscopic techniques serological detection of

antitoxin

Water hygiene

Rehydration in severe

cases tetracycline

TMP-SMZ

No prominent Rice-water stools

Non-bacterial causes

Cryptosporidium Vehicle (water food) fecal-oral

Intracellular growth

Acid-fast staining ruling out bacteria

Water treatment proper food

handling

None paromomycin

used sometimes

Often Not usually

Resistant to chlorine disinfectio

n

Rotavirus Fecal-oral vehicle fomite ndash Usually not

performedOral live

virus vaccine Rehydration Often No Severe in babies

Other Viruses Fecal-oral vehicle - Usually not performed Hygiene Rehydration Sometimes No

Acute Diarrhea

with Vomiting

(Food Poisoning)

Staphylococcus aureus exotoxin

Vehicle (food)

Heat-stable exotoxin

Usually based on

epidemiological evidence

Proper food handling None Not Usually No

Suspect in foods with high salt or

sugar content

Bacillus cereusHeat-stable toxin heat-labile toxin

Microscopic analysis of

food or stool

Two forms emetic and diarrheal

Clostridium perfringens

Heat-labile toxin

Detection of toxin in stool

Acute abdominal

pain

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

FeaturesChronic Diarrhea Enteroaggregativ

e E coli (EAEC)Vehicle (food

water) fecal-oral

Difficult to distinguish

from other E coli

None or ciprofloxacin No

Sometimes mucus

also

Chronic in the

malnourished

Cyclospora cayetanensis

Fecal-oral vehicle Invasiveness Stool examination

PCR

Washing cooking

food personal hygiene

TMP-SMZ Usually No ndash

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

Chapter 20 Infectious Diseases Affecting the Cardiovascular and lymphatic systems

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Acute Endocarditis

Staphylococcus aureus Parenteral Attachment Blood culture Aseptic surgery

injections

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Acute onset high fatality rate

Subacute Endocarditis

Alpha-hemolytic streptococci

Endogenous transfer of

normal biota to bloodstream

Attachment Blood culture

Prophylactic antibiotics before

invasive procedures

Penicillin or vancomycin plus aminoglycoside surgery may be

necessary

Slower onset

Septicemia Bacteria or fungiParenteral

endogenous transfer

Cell wall or membrane

componentsBlood culture -

Broad-spectrum antibiotic until

identification and susceptibilities

tested

Plague Yersinia pestis

Vector biological also droplet contact

(pneumonic) and direct contact

with body fluids

Capsule Yop system

plasminogen activator

Culture or Gram stain of blood or bubo aspirate

Flea and or animal control

vaccine available for high-risk individuals

Streptomycin or gentamicin

Tularemia Francisella tularensis

Vector biological also direct contact

with body fluids from infected

animal airborne

Intracellular growth

Culture dangerous to lab workers and not reliable serology most often used

Live attenuated vaccine for high-risk individuals

Gentamicin or streptomycin

Lyme Disease Borrelia burgdorferi Vector biological Antigenic shifting adhesins

ELISA for Ab PCR Tick avoidance

Doxycycline andor amoxicillin (3ndash4

weeks) also cephalosporins and

penicillin

Infectious Mononucleosis

Epstein-Barr virus (EBV)

Direct indirect contact

parenteral

Latency ability to incorporate into

host DNA

Differential blood count Monospot

test for heterophile antibody

specific ELISA

ndash Supportive Most common in teens

Cytomegalovirus (CMV)

Direct indirect contact

parenteral vertical

Latency ability to fuse cells

Virus isolation and growth ELISA or PCR

tests

Vaccine in trials

Only for immunosuppressed

patients not usually for

mononucleosis

More common in adults dangerous to

fetus

Hemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Yellow fever Yellow fever virus Biological vector Disruption of clotting factors ELISA PCR Live attenuated

vaccine available Supportive Accompanied by jaundice

Dengue Fever Dengue fever virus Biological vector Disruption of clotting factors Rise in IgM titers

Live attenuated vaccine being

testedSupportive

ldquoBreakbone feverrdquomdashso named due to

severe pain

Ebola andor Marburg

Ebola virus Marburg virus

Direct contact body fluids

Disruption of clotting factors

PCR viral culture (conducted at

CDC)ndash Supportive

Massive hemorrhage rash

sometimes present

Lassa Fever Lassa fever virus

Droplet contact (aerosolized

rodent excretions)

direct contact with infected

fluids

Disruption of clotting factors ELISA Avoiding rats

safe food storage RibavirinChest pain

deafness as long-term sequelae

Nonhemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Brucellosis Brucella abortus or B suis

Direct contact airborne

parenteral (needlesticks)

Intracellular growth

avoidance of destruction by

phagocytes

Gram stain of biopsy material

Animal control pasteurization of

milk

Doxycycline plus (gentamicin or streptomycin)

Undulating fever muscle aches

Q fever Coxiella burnetii Airborne direct contact

Endosporelike structure

Serological tests for antibody

Vaccine for high-risk population Doxycycline

Airborne route of transmission

variable disease presentation

Cat-Scratch Disease Bartonella henselae food-borne Endotoxin

Biopsy of lymph nodes plus Gram staining ELISA (performed by

CDC)

Clean wound sites Azithromycin

History of cat bite or scratch fever not

always present

Trench Fever Bartonella quintana Parenteral (cat scratch or bite) Endotoxin

ELISA (performed by

CDC)Avoid lice Doxycycline or

erythromycin

Endocarditis common 5-day

fever

Ehrlichioses Ehrlichia species Biological vector (lice) - PCR indirect

antibody test Avoid lice Doxycycline Seasonal occurrence (AprilndashOct)

Rocky Mountain

Spotted FeverRickettsia rickettsii Biological vector

(tick)

Induces apoptosis in cells

lining blood vessels

Fluorescent antibody PCR Avoid lice Doxycycline

Most common in east and southeast

United States

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

MalariaPlasmodium

falciparum P vivax P ovale P malariae

Biological vector (mosquito)

vertical

Multiple life stages multiple antigenic types

ability to scavenge

glucose GPI cytoadherence

Blood smear serological methods

Mosquito control use of bed nets no vaccine yet

available prophylactic antiprotozoal

agents

Chloroquine mefloquine artemisinin

Fansidar quinine or proguanil

Anthrax Bacillus anthracis

Vehicle (air soil) indirect contact (animal hides) vehicle (food)

Triple exotoxin capsule

Culture direct fluorescent

antibody tests

Vaccine for high-risk population postexposure

antibiotic prophylaxis

Doxycycline ciprofloxacin

penicillin

HIV Infection and AIDS

Human immunodeficiency

virus 1 or 2

Direct contact (sexual)

parenteral (blood-borne)

vertical (perinatal and via breast

milk)

Attachment syncytia

formation reverse

transcriptase high mutation

rate

Initial screening for antibody followed by

Western blot confirmation of

antibody

Avoidance of contact with infected sex

partner contaminated blood breast

milk

HAART (reverse transcriptase inhibitors plus

protease inhibitors) Fuzeon nonnucleoside RT

inhibitors

Adult T-Cell Leukemia HTLV-I

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Hairy-Cell Leukemia (Possibly) HTLV-II

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Chapter 21 Infectious disease affecting the respiratory system

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Rhinitis Approximately 200 viruses

Indirect contact droplet contact

Attachment proteins most

symptoms induced by host

response

Not necessary Hygiene practices For symptoms only

Sinusitis Various bacteria often mixed

infection

Endogenous (opportunism)

Culture not usually

performed diagnosis based

Broad-spectrum antibiotics

Much more common than fungal

on clinical presentation occasionally X rays or other

imaging technique used

Various fungi

Introduction by trauma or

opportunisticOvergrowrth

Same

Physical removal of fungus in severe cases antifungals

used

Suspect in immunocompromised

patients

Otitis Media

Streptococcus pneumoniae

Endogenous (may follow

upper respiratory tract infection by S pneumoniae or

other microorganisms)

Capsule hemolysin

Usually relies on clinical

symptoms and failure to resolve within 72 hours

Pneumococcal conjugate vaccine

(heptavalent)

Wait for resolution if needed

amoxicillin (are high rates of resistance) or amoxicillin 1113106

clavalanate or cefuroxine

ndash

Haemophilus influenzae

Endogenous (follows upper

respiratory tract infection)

Capsule fimbriae Same Hib vaccine Same as for S pneumoniae ndash

Other bacteria Endogenous ndash Same None

Wait for resolution if needed a broad-spectrum antibiotic

(azithromycin) might be used in

absence of etiologic diagnosis

Suspect if fully vaccinated against

other two

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Pharyngitis

Streptococcus pyogenes

Droplet or direct contact

LTA M protein hyaluronic acid

capsule SLS and SLO

superantigens

Beta-hemolytic on blood agar sensitive to bacitracin rapid

antigen tests

Hygiene practices

Penicillin cephalexin in

penicillin-allergic

Generally more severe than viral

pharyngitis

Viruses All forms of contact ndash

Goal is to rule out S pyogenes further diagnosis usually

not performed

Hygiene practices

Symptom relief only

Hoarseness frequently

accompanies viral pharyngitis

Diphtheria Corynebacterium diphtheriae

Droplet contact direct contact or indirect contact

with contaminated

Exotoxin diphtheria toxin

Tellurite mediummdashgrayblack colonies

club-shaped morphology on

Gram stain

Diphtheria toxoid vaccine (part of

DTaP)

Antitoxin plus penicillin or

erythromycin

fomitestreatment begun before definitive

identification

Pertussis (Whooping

Cough)

Bordetella pertussis Droplet contact

FHA (adhesion) pertussis toxin and tracheal

cytotoxin endotoxin

Grown on B-G charcoal or potato-

glycerol agar diagnosis can be

made on symptoms

Acellular vaccine (DTaP)

erythromycin or trimethoprim-

sulfamethoxazole for contacts

Mainly supportive erythromycin to

decrease communicability

RSV DiseaseRespiratory

syncytial virus (RSV)

Droplet and indirect contact

Syncytia formation

Direct antigen testing

Passive antibody in high-risk

children

Ribavirin in severe cases

Influenza Influenza A B and C viruses

Droplet contact direct contact some indirect

contact

Glycoprotein spikes overall

ability to change genetically

Viral culture (3ndash10 days) or rapid

antigen-based or PCR tests

Killed injected vaccine or inhaled live attenuated

vaccinemdashtaken annually

Amantadine rimantadine zanamivir or oseltamivir

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Tuberculosis

Mycobacterium tuberculosis

Vehicle (airborne)

Lipids in wall ability to

stimulate strong cell-mediated

immunity (CMI)

Rapid methods plus culture initial tests are skin testing and

chest X ray

Avoiding airborne M

tuberculosis BCG vaccine in other countries

Isoniazid rifampin and pyrazinamide 1113106 ethambutol or streptomycin for

varying lengths of time (always lengthy) if

resistant two other drugs added

to regimen

Responsible for nearly all TB except

for HIV

Mycobacterium avium complex

Vehicle (airborne) ndash Positive blood

culture

Rifabutin or azithromycin given to AIDS

patients at risk

Azithromycin or clarithromycin plus

one additional antibiotic

Suspect this in HIV-positive patients

PneumoniaStreptococcus pneumoniae

Droplet contact or endogenous

transferCapsule

Gram stain often diagnostic alpha-

hemolytic on blood agar

Pneumococcal polysaccharide

vaccine (23-valent)

Cefotaxime ceftriaxone ketek much resistance

Patient usually severely ill

Legionella species Vehicle (water droplets) ndash

Requires selective charcoal yeast extract agar

serology unreliable

ndashFluoroquinolone

azithromycin clarithromycin

Mild pneumonias in healthy people can be severe in elderly

or immunocompromised

Mycoplasma pneumoniae

Droplet contact Adhesins Rule out other etiologic agents

No vaccine no permanent immunity

Recommended not to treat in most

cases doxycycline or macrolides may

be used if

Usually mild ldquowalking pneumoniardquo

necessary

Hantavirus

Vehiclemdashairborne virus emitted from

rodents

Ability to induce inflammatory

response

Serology (IgM) PCR identification of antigen in tissue

Avoid mouse habitats and

droppingsSupportive Rapid onset high

mortality rate

SARS-associated coronavirus

Droplet direct contact

Rule out other agents serology

PCRndash Supportive Rapid onset

Histoplasma capsulatum

Vehiclemdashinhalation of

contaminated soil

Survival in phagocytes

Usually serological (rising Ab titers)

Avoid contaminated soil bat bird

droppings

Amphotericin B andor itraconazole

Many infections asymptomatic

Pneumocystis jiroveci Droplet contact ndash Immunofluorescence

Antibiotics given to AIDS patients to prevent this

Trimethoprim- sulfamethoxazole

Vast majority occur in AIDS patients

Nosocomial Pneumonia

Gram-negative and gram-positive

bacteria from upper respiratory tract or stomach

Endogenous (aspiration) Culture of lung fluids

Elevating patientrsquos head preoperative

education care of respiratory

equipment

Broad-spectrum antibiotics

Chapter 22 Infectious diseases affecting the GIT

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Dental CariesStreptococcus mutans Streptococcus sobrinus

othersDirect contact Adhesion acid

production -Oral hygiene

fluoride supplementation

Removal of diseased tooth

material

Periodontitis

Polymicrobial community including

some or all of Tannerella forsythus

Actinobacillus actinomycetemcomitans

Porphyromonas gingivalis others

Induction of inflammation Oral hygiene

Removal of plaque and calculus gum

reconstruction tetracycline

Necrotizing Ulcerative

Gingivitis and Periodontitis

Polymicrobial community (Treponema

vincentii Prevotella intermedia

Fusobacterium species)

Inflammation Oral hygiene

Debridement of damaged tissue metronidazole

clindamycin

Mumps Mumps virus (genus Paramyxovirus) Droplet contact

Spike-induced syncytium formation

Clinical fluorescent Ag tests ELISA for

Ab

MMR live attenuated

vaccineSupportive

Gastritis and Helicobacter pylori Adhesions ELISA None Antibiotics plus

Gastric Ulcers urease endoscopy

acid suppressors (clarithromycin or

metronidazole plus omeprazole

or bismuth subsalicylate)

DiseaseAcute

Diarrhea

Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

Features

Bacterial Causes

SalmonellaVehicle (food

beverage) fecal-oral

Adhesins endotoxin

Stool culture not

usually necessary

Food hygiene and

personal hygiene

Rehydration no antibiotic

for uncomplicated

disease

Usually Sometimes

Often associated

with chickens reptiles

Shigella Fecal-oral

Endotoxin enterotoxin

shiga toxins in some strains

Stool culture antigen

testing for shiga toxin

Food hygiene and

personal hygiene

TMP-SMZ rehydration Often Often Very low

ID50

Shiga-toxin- producing E coli O157H7 (EHEC)

Vehicle (food beverage) fecal-

oral

Shiga toxins proteins for attachment secretion

effacement

Stool culture antigen

testing for shiga toxin

Avoid live E coli (cook meat and

clean vegetables)

Antibiotics contraindicated supportive

measures

Often UsuallyHemolytic

uremic syndrome

Other E coli (non-shiga-toxin- producing)

Vehicle fecal-oral

Various proteins for attachment secretion

effacement heat-labile

andor heat- stable

exotoxins invasiveness

Stool culture not usually

necessary in absence of blood fever

Food and personal hygiene

Rehydration Sometimes SometimesEIEC ETEC EPEC

Campylobacter Vehicle (food water) fecal-oral

Adhesins exotoxin

induction of autoimmunity

Stool culture not usually necessary dark-field

microscopy

Food and personal hygiene

Rehydration erythromycin

in severe cases

(antibiotic resistance

rising)

Usually NoGuillain-

Barreacute syndrome

Yersinia Vehicle (food Intracellular Cold- Food and None in most Usually Occasionall Severe

water) fecal-oral indirect contact growth enrichment

stool culturepersonal hygiene

cases doxycycline or TMP-SMZ for bacteremia

y abdominal pain

Clostridium difficile

Endogenous (normal biota)

Enterotoxins A and B

Stool culture PCR

ELISA demonstration of toxins

in stool

ndash

Withdrawal of antibiotic in severe cases

metronidazole or vancomycin

SometimesNot

usually mucus

Antibiotic- associated diarrhea

Vibrio choleraeVehicle (water

and some foods) fecal-oral

Cholera toxin (CT)

Clinical diagnosis

microscopic techniques serological detection of

antitoxin

Water hygiene

Rehydration in severe

cases tetracycline

TMP-SMZ

No prominent Rice-water stools

Non-bacterial causes

Cryptosporidium Vehicle (water food) fecal-oral

Intracellular growth

Acid-fast staining ruling out bacteria

Water treatment proper food

handling

None paromomycin

used sometimes

Often Not usually

Resistant to chlorine disinfectio

n

Rotavirus Fecal-oral vehicle fomite ndash Usually not

performedOral live

virus vaccine Rehydration Often No Severe in babies

Other Viruses Fecal-oral vehicle - Usually not performed Hygiene Rehydration Sometimes No

Acute Diarrhea

with Vomiting

(Food Poisoning)

Staphylococcus aureus exotoxin

Vehicle (food)

Heat-stable exotoxin

Usually based on

epidemiological evidence

Proper food handling None Not Usually No

Suspect in foods with high salt or

sugar content

Bacillus cereusHeat-stable toxin heat-labile toxin

Microscopic analysis of

food or stool

Two forms emetic and diarrheal

Clostridium perfringens

Heat-labile toxin

Detection of toxin in stool

Acute abdominal

pain

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

FeaturesChronic Diarrhea Enteroaggregativ

e E coli (EAEC)Vehicle (food

water) fecal-oral

Difficult to distinguish

from other E coli

None or ciprofloxacin No

Sometimes mucus

also

Chronic in the

malnourished

Cyclospora cayetanensis

Fecal-oral vehicle Invasiveness Stool examination

PCR

Washing cooking

food personal hygiene

TMP-SMZ Usually No ndash

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

Hemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Yellow fever Yellow fever virus Biological vector Disruption of clotting factors ELISA PCR Live attenuated

vaccine available Supportive Accompanied by jaundice

Dengue Fever Dengue fever virus Biological vector Disruption of clotting factors Rise in IgM titers

Live attenuated vaccine being

testedSupportive

ldquoBreakbone feverrdquomdashso named due to

severe pain

Ebola andor Marburg

Ebola virus Marburg virus

Direct contact body fluids

Disruption of clotting factors

PCR viral culture (conducted at

CDC)ndash Supportive

Massive hemorrhage rash

sometimes present

Lassa Fever Lassa fever virus

Droplet contact (aerosolized

rodent excretions)

direct contact with infected

fluids

Disruption of clotting factors ELISA Avoiding rats

safe food storage RibavirinChest pain

deafness as long-term sequelae

Nonhemmorhagic Fever

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Brucellosis Brucella abortus or B suis

Direct contact airborne

parenteral (needlesticks)

Intracellular growth

avoidance of destruction by

phagocytes

Gram stain of biopsy material

Animal control pasteurization of

milk

Doxycycline plus (gentamicin or streptomycin)

Undulating fever muscle aches

Q fever Coxiella burnetii Airborne direct contact

Endosporelike structure

Serological tests for antibody

Vaccine for high-risk population Doxycycline

Airborne route of transmission

variable disease presentation

Cat-Scratch Disease Bartonella henselae food-borne Endotoxin

Biopsy of lymph nodes plus Gram staining ELISA (performed by

CDC)

Clean wound sites Azithromycin

History of cat bite or scratch fever not

always present

Trench Fever Bartonella quintana Parenteral (cat scratch or bite) Endotoxin

ELISA (performed by

CDC)Avoid lice Doxycycline or

erythromycin

Endocarditis common 5-day

fever

Ehrlichioses Ehrlichia species Biological vector (lice) - PCR indirect

antibody test Avoid lice Doxycycline Seasonal occurrence (AprilndashOct)

Rocky Mountain

Spotted FeverRickettsia rickettsii Biological vector

(tick)

Induces apoptosis in cells

lining blood vessels

Fluorescent antibody PCR Avoid lice Doxycycline

Most common in east and southeast

United States

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

MalariaPlasmodium

falciparum P vivax P ovale P malariae

Biological vector (mosquito)

vertical

Multiple life stages multiple antigenic types

ability to scavenge

glucose GPI cytoadherence

Blood smear serological methods

Mosquito control use of bed nets no vaccine yet

available prophylactic antiprotozoal

agents

Chloroquine mefloquine artemisinin

Fansidar quinine or proguanil

Anthrax Bacillus anthracis

Vehicle (air soil) indirect contact (animal hides) vehicle (food)

Triple exotoxin capsule

Culture direct fluorescent

antibody tests

Vaccine for high-risk population postexposure

antibiotic prophylaxis

Doxycycline ciprofloxacin

penicillin

HIV Infection and AIDS

Human immunodeficiency

virus 1 or 2

Direct contact (sexual)

parenteral (blood-borne)

vertical (perinatal and via breast

milk)

Attachment syncytia

formation reverse

transcriptase high mutation

rate

Initial screening for antibody followed by

Western blot confirmation of

antibody

Avoidance of contact with infected sex

partner contaminated blood breast

milk

HAART (reverse transcriptase inhibitors plus

protease inhibitors) Fuzeon nonnucleoside RT

inhibitors

Adult T-Cell Leukemia HTLV-I

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Hairy-Cell Leukemia (Possibly) HTLV-II

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Chapter 21 Infectious disease affecting the respiratory system

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Rhinitis Approximately 200 viruses

Indirect contact droplet contact

Attachment proteins most

symptoms induced by host

response

Not necessary Hygiene practices For symptoms only

Sinusitis Various bacteria often mixed

infection

Endogenous (opportunism)

Culture not usually

performed diagnosis based

Broad-spectrum antibiotics

Much more common than fungal

on clinical presentation occasionally X rays or other

imaging technique used

Various fungi

Introduction by trauma or

opportunisticOvergrowrth

Same

Physical removal of fungus in severe cases antifungals

used

Suspect in immunocompromised

patients

Otitis Media

Streptococcus pneumoniae

Endogenous (may follow

upper respiratory tract infection by S pneumoniae or

other microorganisms)

Capsule hemolysin

Usually relies on clinical

symptoms and failure to resolve within 72 hours

Pneumococcal conjugate vaccine

(heptavalent)

Wait for resolution if needed

amoxicillin (are high rates of resistance) or amoxicillin 1113106

clavalanate or cefuroxine

ndash

Haemophilus influenzae

Endogenous (follows upper

respiratory tract infection)

Capsule fimbriae Same Hib vaccine Same as for S pneumoniae ndash

Other bacteria Endogenous ndash Same None

Wait for resolution if needed a broad-spectrum antibiotic

(azithromycin) might be used in

absence of etiologic diagnosis

Suspect if fully vaccinated against

other two

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Pharyngitis

Streptococcus pyogenes

Droplet or direct contact

LTA M protein hyaluronic acid

capsule SLS and SLO

superantigens

Beta-hemolytic on blood agar sensitive to bacitracin rapid

antigen tests

Hygiene practices

Penicillin cephalexin in

penicillin-allergic

Generally more severe than viral

pharyngitis

Viruses All forms of contact ndash

Goal is to rule out S pyogenes further diagnosis usually

not performed

Hygiene practices

Symptom relief only

Hoarseness frequently

accompanies viral pharyngitis

Diphtheria Corynebacterium diphtheriae

Droplet contact direct contact or indirect contact

with contaminated

Exotoxin diphtheria toxin

Tellurite mediummdashgrayblack colonies

club-shaped morphology on

Gram stain

Diphtheria toxoid vaccine (part of

DTaP)

Antitoxin plus penicillin or

erythromycin

fomitestreatment begun before definitive

identification

Pertussis (Whooping

Cough)

Bordetella pertussis Droplet contact

FHA (adhesion) pertussis toxin and tracheal

cytotoxin endotoxin

Grown on B-G charcoal or potato-

glycerol agar diagnosis can be

made on symptoms

Acellular vaccine (DTaP)

erythromycin or trimethoprim-

sulfamethoxazole for contacts

Mainly supportive erythromycin to

decrease communicability

RSV DiseaseRespiratory

syncytial virus (RSV)

Droplet and indirect contact

Syncytia formation

Direct antigen testing

Passive antibody in high-risk

children

Ribavirin in severe cases

Influenza Influenza A B and C viruses

Droplet contact direct contact some indirect

contact

Glycoprotein spikes overall

ability to change genetically

Viral culture (3ndash10 days) or rapid

antigen-based or PCR tests

Killed injected vaccine or inhaled live attenuated

vaccinemdashtaken annually

Amantadine rimantadine zanamivir or oseltamivir

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Tuberculosis

Mycobacterium tuberculosis

Vehicle (airborne)

Lipids in wall ability to

stimulate strong cell-mediated

immunity (CMI)

Rapid methods plus culture initial tests are skin testing and

chest X ray

Avoiding airborne M

tuberculosis BCG vaccine in other countries

Isoniazid rifampin and pyrazinamide 1113106 ethambutol or streptomycin for

varying lengths of time (always lengthy) if

resistant two other drugs added

to regimen

Responsible for nearly all TB except

for HIV

Mycobacterium avium complex

Vehicle (airborne) ndash Positive blood

culture

Rifabutin or azithromycin given to AIDS

patients at risk

Azithromycin or clarithromycin plus

one additional antibiotic

Suspect this in HIV-positive patients

PneumoniaStreptococcus pneumoniae

Droplet contact or endogenous

transferCapsule

Gram stain often diagnostic alpha-

hemolytic on blood agar

Pneumococcal polysaccharide

vaccine (23-valent)

Cefotaxime ceftriaxone ketek much resistance

Patient usually severely ill

Legionella species Vehicle (water droplets) ndash

Requires selective charcoal yeast extract agar

serology unreliable

ndashFluoroquinolone

azithromycin clarithromycin

Mild pneumonias in healthy people can be severe in elderly

or immunocompromised

Mycoplasma pneumoniae

Droplet contact Adhesins Rule out other etiologic agents

No vaccine no permanent immunity

Recommended not to treat in most

cases doxycycline or macrolides may

be used if

Usually mild ldquowalking pneumoniardquo

necessary

Hantavirus

Vehiclemdashairborne virus emitted from

rodents

Ability to induce inflammatory

response

Serology (IgM) PCR identification of antigen in tissue

Avoid mouse habitats and

droppingsSupportive Rapid onset high

mortality rate

SARS-associated coronavirus

Droplet direct contact

Rule out other agents serology

PCRndash Supportive Rapid onset

Histoplasma capsulatum

Vehiclemdashinhalation of

contaminated soil

Survival in phagocytes

Usually serological (rising Ab titers)

Avoid contaminated soil bat bird

droppings

Amphotericin B andor itraconazole

Many infections asymptomatic

Pneumocystis jiroveci Droplet contact ndash Immunofluorescence

Antibiotics given to AIDS patients to prevent this

Trimethoprim- sulfamethoxazole

Vast majority occur in AIDS patients

Nosocomial Pneumonia

Gram-negative and gram-positive

bacteria from upper respiratory tract or stomach

Endogenous (aspiration) Culture of lung fluids

Elevating patientrsquos head preoperative

education care of respiratory

equipment

Broad-spectrum antibiotics

Chapter 22 Infectious diseases affecting the GIT

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Dental CariesStreptococcus mutans Streptococcus sobrinus

othersDirect contact Adhesion acid

production -Oral hygiene

fluoride supplementation

Removal of diseased tooth

material

Periodontitis

Polymicrobial community including

some or all of Tannerella forsythus

Actinobacillus actinomycetemcomitans

Porphyromonas gingivalis others

Induction of inflammation Oral hygiene

Removal of plaque and calculus gum

reconstruction tetracycline

Necrotizing Ulcerative

Gingivitis and Periodontitis

Polymicrobial community (Treponema

vincentii Prevotella intermedia

Fusobacterium species)

Inflammation Oral hygiene

Debridement of damaged tissue metronidazole

clindamycin

Mumps Mumps virus (genus Paramyxovirus) Droplet contact

Spike-induced syncytium formation

Clinical fluorescent Ag tests ELISA for

Ab

MMR live attenuated

vaccineSupportive

Gastritis and Helicobacter pylori Adhesions ELISA None Antibiotics plus

Gastric Ulcers urease endoscopy

acid suppressors (clarithromycin or

metronidazole plus omeprazole

or bismuth subsalicylate)

DiseaseAcute

Diarrhea

Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

Features

Bacterial Causes

SalmonellaVehicle (food

beverage) fecal-oral

Adhesins endotoxin

Stool culture not

usually necessary

Food hygiene and

personal hygiene

Rehydration no antibiotic

for uncomplicated

disease

Usually Sometimes

Often associated

with chickens reptiles

Shigella Fecal-oral

Endotoxin enterotoxin

shiga toxins in some strains

Stool culture antigen

testing for shiga toxin

Food hygiene and

personal hygiene

TMP-SMZ rehydration Often Often Very low

ID50

Shiga-toxin- producing E coli O157H7 (EHEC)

Vehicle (food beverage) fecal-

oral

Shiga toxins proteins for attachment secretion

effacement

Stool culture antigen

testing for shiga toxin

Avoid live E coli (cook meat and

clean vegetables)

Antibiotics contraindicated supportive

measures

Often UsuallyHemolytic

uremic syndrome

Other E coli (non-shiga-toxin- producing)

Vehicle fecal-oral

Various proteins for attachment secretion

effacement heat-labile

andor heat- stable

exotoxins invasiveness

Stool culture not usually

necessary in absence of blood fever

Food and personal hygiene

Rehydration Sometimes SometimesEIEC ETEC EPEC

Campylobacter Vehicle (food water) fecal-oral

Adhesins exotoxin

induction of autoimmunity

Stool culture not usually necessary dark-field

microscopy

Food and personal hygiene

Rehydration erythromycin

in severe cases

(antibiotic resistance

rising)

Usually NoGuillain-

Barreacute syndrome

Yersinia Vehicle (food Intracellular Cold- Food and None in most Usually Occasionall Severe

water) fecal-oral indirect contact growth enrichment

stool culturepersonal hygiene

cases doxycycline or TMP-SMZ for bacteremia

y abdominal pain

Clostridium difficile

Endogenous (normal biota)

Enterotoxins A and B

Stool culture PCR

ELISA demonstration of toxins

in stool

ndash

Withdrawal of antibiotic in severe cases

metronidazole or vancomycin

SometimesNot

usually mucus

Antibiotic- associated diarrhea

Vibrio choleraeVehicle (water

and some foods) fecal-oral

Cholera toxin (CT)

Clinical diagnosis

microscopic techniques serological detection of

antitoxin

Water hygiene

Rehydration in severe

cases tetracycline

TMP-SMZ

No prominent Rice-water stools

Non-bacterial causes

Cryptosporidium Vehicle (water food) fecal-oral

Intracellular growth

Acid-fast staining ruling out bacteria

Water treatment proper food

handling

None paromomycin

used sometimes

Often Not usually

Resistant to chlorine disinfectio

n

Rotavirus Fecal-oral vehicle fomite ndash Usually not

performedOral live

virus vaccine Rehydration Often No Severe in babies

Other Viruses Fecal-oral vehicle - Usually not performed Hygiene Rehydration Sometimes No

Acute Diarrhea

with Vomiting

(Food Poisoning)

Staphylococcus aureus exotoxin

Vehicle (food)

Heat-stable exotoxin

Usually based on

epidemiological evidence

Proper food handling None Not Usually No

Suspect in foods with high salt or

sugar content

Bacillus cereusHeat-stable toxin heat-labile toxin

Microscopic analysis of

food or stool

Two forms emetic and diarrheal

Clostridium perfringens

Heat-labile toxin

Detection of toxin in stool

Acute abdominal

pain

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

FeaturesChronic Diarrhea Enteroaggregativ

e E coli (EAEC)Vehicle (food

water) fecal-oral

Difficult to distinguish

from other E coli

None or ciprofloxacin No

Sometimes mucus

also

Chronic in the

malnourished

Cyclospora cayetanensis

Fecal-oral vehicle Invasiveness Stool examination

PCR

Washing cooking

food personal hygiene

TMP-SMZ Usually No ndash

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

MalariaPlasmodium

falciparum P vivax P ovale P malariae

Biological vector (mosquito)

vertical

Multiple life stages multiple antigenic types

ability to scavenge

glucose GPI cytoadherence

Blood smear serological methods

Mosquito control use of bed nets no vaccine yet

available prophylactic antiprotozoal

agents

Chloroquine mefloquine artemisinin

Fansidar quinine or proguanil

Anthrax Bacillus anthracis

Vehicle (air soil) indirect contact (animal hides) vehicle (food)

Triple exotoxin capsule

Culture direct fluorescent

antibody tests

Vaccine for high-risk population postexposure

antibiotic prophylaxis

Doxycycline ciprofloxacin

penicillin

HIV Infection and AIDS

Human immunodeficiency

virus 1 or 2

Direct contact (sexual)

parenteral (blood-borne)

vertical (perinatal and via breast

milk)

Attachment syncytia

formation reverse

transcriptase high mutation

rate

Initial screening for antibody followed by

Western blot confirmation of

antibody

Avoidance of contact with infected sex

partner contaminated blood breast

milk

HAART (reverse transcriptase inhibitors plus

protease inhibitors) Fuzeon nonnucleoside RT

inhibitors

Adult T-Cell Leukemia HTLV-I

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Hairy-Cell Leukemia (Possibly) HTLV-II

Unclearmdash blood-borne

transmission implicated

Induction of malignant state

Differential blood count followed by histological examination of excised lymph

node tissue

Antineoplastic drugs interferon

alpha

Chapter 21 Infectious disease affecting the respiratory system

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Rhinitis Approximately 200 viruses

Indirect contact droplet contact

Attachment proteins most

symptoms induced by host

response

Not necessary Hygiene practices For symptoms only

Sinusitis Various bacteria often mixed

infection

Endogenous (opportunism)

Culture not usually

performed diagnosis based

Broad-spectrum antibiotics

Much more common than fungal

on clinical presentation occasionally X rays or other

imaging technique used

Various fungi

Introduction by trauma or

opportunisticOvergrowrth

Same

Physical removal of fungus in severe cases antifungals

used

Suspect in immunocompromised

patients

Otitis Media

Streptococcus pneumoniae

Endogenous (may follow

upper respiratory tract infection by S pneumoniae or

other microorganisms)

Capsule hemolysin

Usually relies on clinical

symptoms and failure to resolve within 72 hours

Pneumococcal conjugate vaccine

(heptavalent)

Wait for resolution if needed

amoxicillin (are high rates of resistance) or amoxicillin 1113106

clavalanate or cefuroxine

ndash

Haemophilus influenzae

Endogenous (follows upper

respiratory tract infection)

Capsule fimbriae Same Hib vaccine Same as for S pneumoniae ndash

Other bacteria Endogenous ndash Same None

Wait for resolution if needed a broad-spectrum antibiotic

(azithromycin) might be used in

absence of etiologic diagnosis

Suspect if fully vaccinated against

other two

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Pharyngitis

Streptococcus pyogenes

Droplet or direct contact

LTA M protein hyaluronic acid

capsule SLS and SLO

superantigens

Beta-hemolytic on blood agar sensitive to bacitracin rapid

antigen tests

Hygiene practices

Penicillin cephalexin in

penicillin-allergic

Generally more severe than viral

pharyngitis

Viruses All forms of contact ndash

Goal is to rule out S pyogenes further diagnosis usually

not performed

Hygiene practices

Symptom relief only

Hoarseness frequently

accompanies viral pharyngitis

Diphtheria Corynebacterium diphtheriae

Droplet contact direct contact or indirect contact

with contaminated

Exotoxin diphtheria toxin

Tellurite mediummdashgrayblack colonies

club-shaped morphology on

Gram stain

Diphtheria toxoid vaccine (part of

DTaP)

Antitoxin plus penicillin or

erythromycin

fomitestreatment begun before definitive

identification

Pertussis (Whooping

Cough)

Bordetella pertussis Droplet contact

FHA (adhesion) pertussis toxin and tracheal

cytotoxin endotoxin

Grown on B-G charcoal or potato-

glycerol agar diagnosis can be

made on symptoms

Acellular vaccine (DTaP)

erythromycin or trimethoprim-

sulfamethoxazole for contacts

Mainly supportive erythromycin to

decrease communicability

RSV DiseaseRespiratory

syncytial virus (RSV)

Droplet and indirect contact

Syncytia formation

Direct antigen testing

Passive antibody in high-risk

children

Ribavirin in severe cases

Influenza Influenza A B and C viruses

Droplet contact direct contact some indirect

contact

Glycoprotein spikes overall

ability to change genetically

Viral culture (3ndash10 days) or rapid

antigen-based or PCR tests

Killed injected vaccine or inhaled live attenuated

vaccinemdashtaken annually

Amantadine rimantadine zanamivir or oseltamivir

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Tuberculosis

Mycobacterium tuberculosis

Vehicle (airborne)

Lipids in wall ability to

stimulate strong cell-mediated

immunity (CMI)

Rapid methods plus culture initial tests are skin testing and

chest X ray

Avoiding airborne M

tuberculosis BCG vaccine in other countries

Isoniazid rifampin and pyrazinamide 1113106 ethambutol or streptomycin for

varying lengths of time (always lengthy) if

resistant two other drugs added

to regimen

Responsible for nearly all TB except

for HIV

Mycobacterium avium complex

Vehicle (airborne) ndash Positive blood

culture

Rifabutin or azithromycin given to AIDS

patients at risk

Azithromycin or clarithromycin plus

one additional antibiotic

Suspect this in HIV-positive patients

PneumoniaStreptococcus pneumoniae

Droplet contact or endogenous

transferCapsule

Gram stain often diagnostic alpha-

hemolytic on blood agar

Pneumococcal polysaccharide

vaccine (23-valent)

Cefotaxime ceftriaxone ketek much resistance

Patient usually severely ill

Legionella species Vehicle (water droplets) ndash

Requires selective charcoal yeast extract agar

serology unreliable

ndashFluoroquinolone

azithromycin clarithromycin

Mild pneumonias in healthy people can be severe in elderly

or immunocompromised

Mycoplasma pneumoniae

Droplet contact Adhesins Rule out other etiologic agents

No vaccine no permanent immunity

Recommended not to treat in most

cases doxycycline or macrolides may

be used if

Usually mild ldquowalking pneumoniardquo

necessary

Hantavirus

Vehiclemdashairborne virus emitted from

rodents

Ability to induce inflammatory

response

Serology (IgM) PCR identification of antigen in tissue

Avoid mouse habitats and

droppingsSupportive Rapid onset high

mortality rate

SARS-associated coronavirus

Droplet direct contact

Rule out other agents serology

PCRndash Supportive Rapid onset

Histoplasma capsulatum

Vehiclemdashinhalation of

contaminated soil

Survival in phagocytes

Usually serological (rising Ab titers)

Avoid contaminated soil bat bird

droppings

Amphotericin B andor itraconazole

Many infections asymptomatic

Pneumocystis jiroveci Droplet contact ndash Immunofluorescence

Antibiotics given to AIDS patients to prevent this

Trimethoprim- sulfamethoxazole

Vast majority occur in AIDS patients

Nosocomial Pneumonia

Gram-negative and gram-positive

bacteria from upper respiratory tract or stomach

Endogenous (aspiration) Culture of lung fluids

Elevating patientrsquos head preoperative

education care of respiratory

equipment

Broad-spectrum antibiotics

Chapter 22 Infectious diseases affecting the GIT

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Dental CariesStreptococcus mutans Streptococcus sobrinus

othersDirect contact Adhesion acid

production -Oral hygiene

fluoride supplementation

Removal of diseased tooth

material

Periodontitis

Polymicrobial community including

some or all of Tannerella forsythus

Actinobacillus actinomycetemcomitans

Porphyromonas gingivalis others

Induction of inflammation Oral hygiene

Removal of plaque and calculus gum

reconstruction tetracycline

Necrotizing Ulcerative

Gingivitis and Periodontitis

Polymicrobial community (Treponema

vincentii Prevotella intermedia

Fusobacterium species)

Inflammation Oral hygiene

Debridement of damaged tissue metronidazole

clindamycin

Mumps Mumps virus (genus Paramyxovirus) Droplet contact

Spike-induced syncytium formation

Clinical fluorescent Ag tests ELISA for

Ab

MMR live attenuated

vaccineSupportive

Gastritis and Helicobacter pylori Adhesions ELISA None Antibiotics plus

Gastric Ulcers urease endoscopy

acid suppressors (clarithromycin or

metronidazole plus omeprazole

or bismuth subsalicylate)

DiseaseAcute

Diarrhea

Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

Features

Bacterial Causes

SalmonellaVehicle (food

beverage) fecal-oral

Adhesins endotoxin

Stool culture not

usually necessary

Food hygiene and

personal hygiene

Rehydration no antibiotic

for uncomplicated

disease

Usually Sometimes

Often associated

with chickens reptiles

Shigella Fecal-oral

Endotoxin enterotoxin

shiga toxins in some strains

Stool culture antigen

testing for shiga toxin

Food hygiene and

personal hygiene

TMP-SMZ rehydration Often Often Very low

ID50

Shiga-toxin- producing E coli O157H7 (EHEC)

Vehicle (food beverage) fecal-

oral

Shiga toxins proteins for attachment secretion

effacement

Stool culture antigen

testing for shiga toxin

Avoid live E coli (cook meat and

clean vegetables)

Antibiotics contraindicated supportive

measures

Often UsuallyHemolytic

uremic syndrome

Other E coli (non-shiga-toxin- producing)

Vehicle fecal-oral

Various proteins for attachment secretion

effacement heat-labile

andor heat- stable

exotoxins invasiveness

Stool culture not usually

necessary in absence of blood fever

Food and personal hygiene

Rehydration Sometimes SometimesEIEC ETEC EPEC

Campylobacter Vehicle (food water) fecal-oral

Adhesins exotoxin

induction of autoimmunity

Stool culture not usually necessary dark-field

microscopy

Food and personal hygiene

Rehydration erythromycin

in severe cases

(antibiotic resistance

rising)

Usually NoGuillain-

Barreacute syndrome

Yersinia Vehicle (food Intracellular Cold- Food and None in most Usually Occasionall Severe

water) fecal-oral indirect contact growth enrichment

stool culturepersonal hygiene

cases doxycycline or TMP-SMZ for bacteremia

y abdominal pain

Clostridium difficile

Endogenous (normal biota)

Enterotoxins A and B

Stool culture PCR

ELISA demonstration of toxins

in stool

ndash

Withdrawal of antibiotic in severe cases

metronidazole or vancomycin

SometimesNot

usually mucus

Antibiotic- associated diarrhea

Vibrio choleraeVehicle (water

and some foods) fecal-oral

Cholera toxin (CT)

Clinical diagnosis

microscopic techniques serological detection of

antitoxin

Water hygiene

Rehydration in severe

cases tetracycline

TMP-SMZ

No prominent Rice-water stools

Non-bacterial causes

Cryptosporidium Vehicle (water food) fecal-oral

Intracellular growth

Acid-fast staining ruling out bacteria

Water treatment proper food

handling

None paromomycin

used sometimes

Often Not usually

Resistant to chlorine disinfectio

n

Rotavirus Fecal-oral vehicle fomite ndash Usually not

performedOral live

virus vaccine Rehydration Often No Severe in babies

Other Viruses Fecal-oral vehicle - Usually not performed Hygiene Rehydration Sometimes No

Acute Diarrhea

with Vomiting

(Food Poisoning)

Staphylococcus aureus exotoxin

Vehicle (food)

Heat-stable exotoxin

Usually based on

epidemiological evidence

Proper food handling None Not Usually No

Suspect in foods with high salt or

sugar content

Bacillus cereusHeat-stable toxin heat-labile toxin

Microscopic analysis of

food or stool

Two forms emetic and diarrheal

Clostridium perfringens

Heat-labile toxin

Detection of toxin in stool

Acute abdominal

pain

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

FeaturesChronic Diarrhea Enteroaggregativ

e E coli (EAEC)Vehicle (food

water) fecal-oral

Difficult to distinguish

from other E coli

None or ciprofloxacin No

Sometimes mucus

also

Chronic in the

malnourished

Cyclospora cayetanensis

Fecal-oral vehicle Invasiveness Stool examination

PCR

Washing cooking

food personal hygiene

TMP-SMZ Usually No ndash

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

on clinical presentation occasionally X rays or other

imaging technique used

Various fungi

Introduction by trauma or

opportunisticOvergrowrth

Same

Physical removal of fungus in severe cases antifungals

used

Suspect in immunocompromised

patients

Otitis Media

Streptococcus pneumoniae

Endogenous (may follow

upper respiratory tract infection by S pneumoniae or

other microorganisms)

Capsule hemolysin

Usually relies on clinical

symptoms and failure to resolve within 72 hours

Pneumococcal conjugate vaccine

(heptavalent)

Wait for resolution if needed

amoxicillin (are high rates of resistance) or amoxicillin 1113106

clavalanate or cefuroxine

ndash

Haemophilus influenzae

Endogenous (follows upper

respiratory tract infection)

Capsule fimbriae Same Hib vaccine Same as for S pneumoniae ndash

Other bacteria Endogenous ndash Same None

Wait for resolution if needed a broad-spectrum antibiotic

(azithromycin) might be used in

absence of etiologic diagnosis

Suspect if fully vaccinated against

other two

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Pharyngitis

Streptococcus pyogenes

Droplet or direct contact

LTA M protein hyaluronic acid

capsule SLS and SLO

superantigens

Beta-hemolytic on blood agar sensitive to bacitracin rapid

antigen tests

Hygiene practices

Penicillin cephalexin in

penicillin-allergic

Generally more severe than viral

pharyngitis

Viruses All forms of contact ndash

Goal is to rule out S pyogenes further diagnosis usually

not performed

Hygiene practices

Symptom relief only

Hoarseness frequently

accompanies viral pharyngitis

Diphtheria Corynebacterium diphtheriae

Droplet contact direct contact or indirect contact

with contaminated

Exotoxin diphtheria toxin

Tellurite mediummdashgrayblack colonies

club-shaped morphology on

Gram stain

Diphtheria toxoid vaccine (part of

DTaP)

Antitoxin plus penicillin or

erythromycin

fomitestreatment begun before definitive

identification

Pertussis (Whooping

Cough)

Bordetella pertussis Droplet contact

FHA (adhesion) pertussis toxin and tracheal

cytotoxin endotoxin

Grown on B-G charcoal or potato-

glycerol agar diagnosis can be

made on symptoms

Acellular vaccine (DTaP)

erythromycin or trimethoprim-

sulfamethoxazole for contacts

Mainly supportive erythromycin to

decrease communicability

RSV DiseaseRespiratory

syncytial virus (RSV)

Droplet and indirect contact

Syncytia formation

Direct antigen testing

Passive antibody in high-risk

children

Ribavirin in severe cases

Influenza Influenza A B and C viruses

Droplet contact direct contact some indirect

contact

Glycoprotein spikes overall

ability to change genetically

Viral culture (3ndash10 days) or rapid

antigen-based or PCR tests

Killed injected vaccine or inhaled live attenuated

vaccinemdashtaken annually

Amantadine rimantadine zanamivir or oseltamivir

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Tuberculosis

Mycobacterium tuberculosis

Vehicle (airborne)

Lipids in wall ability to

stimulate strong cell-mediated

immunity (CMI)

Rapid methods plus culture initial tests are skin testing and

chest X ray

Avoiding airborne M

tuberculosis BCG vaccine in other countries

Isoniazid rifampin and pyrazinamide 1113106 ethambutol or streptomycin for

varying lengths of time (always lengthy) if

resistant two other drugs added

to regimen

Responsible for nearly all TB except

for HIV

Mycobacterium avium complex

Vehicle (airborne) ndash Positive blood

culture

Rifabutin or azithromycin given to AIDS

patients at risk

Azithromycin or clarithromycin plus

one additional antibiotic

Suspect this in HIV-positive patients

PneumoniaStreptococcus pneumoniae

Droplet contact or endogenous

transferCapsule

Gram stain often diagnostic alpha-

hemolytic on blood agar

Pneumococcal polysaccharide

vaccine (23-valent)

Cefotaxime ceftriaxone ketek much resistance

Patient usually severely ill

Legionella species Vehicle (water droplets) ndash

Requires selective charcoal yeast extract agar

serology unreliable

ndashFluoroquinolone

azithromycin clarithromycin

Mild pneumonias in healthy people can be severe in elderly

or immunocompromised

Mycoplasma pneumoniae

Droplet contact Adhesins Rule out other etiologic agents

No vaccine no permanent immunity

Recommended not to treat in most

cases doxycycline or macrolides may

be used if

Usually mild ldquowalking pneumoniardquo

necessary

Hantavirus

Vehiclemdashairborne virus emitted from

rodents

Ability to induce inflammatory

response

Serology (IgM) PCR identification of antigen in tissue

Avoid mouse habitats and

droppingsSupportive Rapid onset high

mortality rate

SARS-associated coronavirus

Droplet direct contact

Rule out other agents serology

PCRndash Supportive Rapid onset

Histoplasma capsulatum

Vehiclemdashinhalation of

contaminated soil

Survival in phagocytes

Usually serological (rising Ab titers)

Avoid contaminated soil bat bird

droppings

Amphotericin B andor itraconazole

Many infections asymptomatic

Pneumocystis jiroveci Droplet contact ndash Immunofluorescence

Antibiotics given to AIDS patients to prevent this

Trimethoprim- sulfamethoxazole

Vast majority occur in AIDS patients

Nosocomial Pneumonia

Gram-negative and gram-positive

bacteria from upper respiratory tract or stomach

Endogenous (aspiration) Culture of lung fluids

Elevating patientrsquos head preoperative

education care of respiratory

equipment

Broad-spectrum antibiotics

Chapter 22 Infectious diseases affecting the GIT

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Dental CariesStreptococcus mutans Streptococcus sobrinus

othersDirect contact Adhesion acid

production -Oral hygiene

fluoride supplementation

Removal of diseased tooth

material

Periodontitis

Polymicrobial community including

some or all of Tannerella forsythus

Actinobacillus actinomycetemcomitans

Porphyromonas gingivalis others

Induction of inflammation Oral hygiene

Removal of plaque and calculus gum

reconstruction tetracycline

Necrotizing Ulcerative

Gingivitis and Periodontitis

Polymicrobial community (Treponema

vincentii Prevotella intermedia

Fusobacterium species)

Inflammation Oral hygiene

Debridement of damaged tissue metronidazole

clindamycin

Mumps Mumps virus (genus Paramyxovirus) Droplet contact

Spike-induced syncytium formation

Clinical fluorescent Ag tests ELISA for

Ab

MMR live attenuated

vaccineSupportive

Gastritis and Helicobacter pylori Adhesions ELISA None Antibiotics plus

Gastric Ulcers urease endoscopy

acid suppressors (clarithromycin or

metronidazole plus omeprazole

or bismuth subsalicylate)

DiseaseAcute

Diarrhea

Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

Features

Bacterial Causes

SalmonellaVehicle (food

beverage) fecal-oral

Adhesins endotoxin

Stool culture not

usually necessary

Food hygiene and

personal hygiene

Rehydration no antibiotic

for uncomplicated

disease

Usually Sometimes

Often associated

with chickens reptiles

Shigella Fecal-oral

Endotoxin enterotoxin

shiga toxins in some strains

Stool culture antigen

testing for shiga toxin

Food hygiene and

personal hygiene

TMP-SMZ rehydration Often Often Very low

ID50

Shiga-toxin- producing E coli O157H7 (EHEC)

Vehicle (food beverage) fecal-

oral

Shiga toxins proteins for attachment secretion

effacement

Stool culture antigen

testing for shiga toxin

Avoid live E coli (cook meat and

clean vegetables)

Antibiotics contraindicated supportive

measures

Often UsuallyHemolytic

uremic syndrome

Other E coli (non-shiga-toxin- producing)

Vehicle fecal-oral

Various proteins for attachment secretion

effacement heat-labile

andor heat- stable

exotoxins invasiveness

Stool culture not usually

necessary in absence of blood fever

Food and personal hygiene

Rehydration Sometimes SometimesEIEC ETEC EPEC

Campylobacter Vehicle (food water) fecal-oral

Adhesins exotoxin

induction of autoimmunity

Stool culture not usually necessary dark-field

microscopy

Food and personal hygiene

Rehydration erythromycin

in severe cases

(antibiotic resistance

rising)

Usually NoGuillain-

Barreacute syndrome

Yersinia Vehicle (food Intracellular Cold- Food and None in most Usually Occasionall Severe

water) fecal-oral indirect contact growth enrichment

stool culturepersonal hygiene

cases doxycycline or TMP-SMZ for bacteremia

y abdominal pain

Clostridium difficile

Endogenous (normal biota)

Enterotoxins A and B

Stool culture PCR

ELISA demonstration of toxins

in stool

ndash

Withdrawal of antibiotic in severe cases

metronidazole or vancomycin

SometimesNot

usually mucus

Antibiotic- associated diarrhea

Vibrio choleraeVehicle (water

and some foods) fecal-oral

Cholera toxin (CT)

Clinical diagnosis

microscopic techniques serological detection of

antitoxin

Water hygiene

Rehydration in severe

cases tetracycline

TMP-SMZ

No prominent Rice-water stools

Non-bacterial causes

Cryptosporidium Vehicle (water food) fecal-oral

Intracellular growth

Acid-fast staining ruling out bacteria

Water treatment proper food

handling

None paromomycin

used sometimes

Often Not usually

Resistant to chlorine disinfectio

n

Rotavirus Fecal-oral vehicle fomite ndash Usually not

performedOral live

virus vaccine Rehydration Often No Severe in babies

Other Viruses Fecal-oral vehicle - Usually not performed Hygiene Rehydration Sometimes No

Acute Diarrhea

with Vomiting

(Food Poisoning)

Staphylococcus aureus exotoxin

Vehicle (food)

Heat-stable exotoxin

Usually based on

epidemiological evidence

Proper food handling None Not Usually No

Suspect in foods with high salt or

sugar content

Bacillus cereusHeat-stable toxin heat-labile toxin

Microscopic analysis of

food or stool

Two forms emetic and diarrheal

Clostridium perfringens

Heat-labile toxin

Detection of toxin in stool

Acute abdominal

pain

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

FeaturesChronic Diarrhea Enteroaggregativ

e E coli (EAEC)Vehicle (food

water) fecal-oral

Difficult to distinguish

from other E coli

None or ciprofloxacin No

Sometimes mucus

also

Chronic in the

malnourished

Cyclospora cayetanensis

Fecal-oral vehicle Invasiveness Stool examination

PCR

Washing cooking

food personal hygiene

TMP-SMZ Usually No ndash

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

fomitestreatment begun before definitive

identification

Pertussis (Whooping

Cough)

Bordetella pertussis Droplet contact

FHA (adhesion) pertussis toxin and tracheal

cytotoxin endotoxin

Grown on B-G charcoal or potato-

glycerol agar diagnosis can be

made on symptoms

Acellular vaccine (DTaP)

erythromycin or trimethoprim-

sulfamethoxazole for contacts

Mainly supportive erythromycin to

decrease communicability

RSV DiseaseRespiratory

syncytial virus (RSV)

Droplet and indirect contact

Syncytia formation

Direct antigen testing

Passive antibody in high-risk

children

Ribavirin in severe cases

Influenza Influenza A B and C viruses

Droplet contact direct contact some indirect

contact

Glycoprotein spikes overall

ability to change genetically

Viral culture (3ndash10 days) or rapid

antigen-based or PCR tests

Killed injected vaccine or inhaled live attenuated

vaccinemdashtaken annually

Amantadine rimantadine zanamivir or oseltamivir

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishing

Features

Tuberculosis

Mycobacterium tuberculosis

Vehicle (airborne)

Lipids in wall ability to

stimulate strong cell-mediated

immunity (CMI)

Rapid methods plus culture initial tests are skin testing and

chest X ray

Avoiding airborne M

tuberculosis BCG vaccine in other countries

Isoniazid rifampin and pyrazinamide 1113106 ethambutol or streptomycin for

varying lengths of time (always lengthy) if

resistant two other drugs added

to regimen

Responsible for nearly all TB except

for HIV

Mycobacterium avium complex

Vehicle (airborne) ndash Positive blood

culture

Rifabutin or azithromycin given to AIDS

patients at risk

Azithromycin or clarithromycin plus

one additional antibiotic

Suspect this in HIV-positive patients

PneumoniaStreptococcus pneumoniae

Droplet contact or endogenous

transferCapsule

Gram stain often diagnostic alpha-

hemolytic on blood agar

Pneumococcal polysaccharide

vaccine (23-valent)

Cefotaxime ceftriaxone ketek much resistance

Patient usually severely ill

Legionella species Vehicle (water droplets) ndash

Requires selective charcoal yeast extract agar

serology unreliable

ndashFluoroquinolone

azithromycin clarithromycin

Mild pneumonias in healthy people can be severe in elderly

or immunocompromised

Mycoplasma pneumoniae

Droplet contact Adhesins Rule out other etiologic agents

No vaccine no permanent immunity

Recommended not to treat in most

cases doxycycline or macrolides may

be used if

Usually mild ldquowalking pneumoniardquo

necessary

Hantavirus

Vehiclemdashairborne virus emitted from

rodents

Ability to induce inflammatory

response

Serology (IgM) PCR identification of antigen in tissue

Avoid mouse habitats and

droppingsSupportive Rapid onset high

mortality rate

SARS-associated coronavirus

Droplet direct contact

Rule out other agents serology

PCRndash Supportive Rapid onset

Histoplasma capsulatum

Vehiclemdashinhalation of

contaminated soil

Survival in phagocytes

Usually serological (rising Ab titers)

Avoid contaminated soil bat bird

droppings

Amphotericin B andor itraconazole

Many infections asymptomatic

Pneumocystis jiroveci Droplet contact ndash Immunofluorescence

Antibiotics given to AIDS patients to prevent this

Trimethoprim- sulfamethoxazole

Vast majority occur in AIDS patients

Nosocomial Pneumonia

Gram-negative and gram-positive

bacteria from upper respiratory tract or stomach

Endogenous (aspiration) Culture of lung fluids

Elevating patientrsquos head preoperative

education care of respiratory

equipment

Broad-spectrum antibiotics

Chapter 22 Infectious diseases affecting the GIT

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Dental CariesStreptococcus mutans Streptococcus sobrinus

othersDirect contact Adhesion acid

production -Oral hygiene

fluoride supplementation

Removal of diseased tooth

material

Periodontitis

Polymicrobial community including

some or all of Tannerella forsythus

Actinobacillus actinomycetemcomitans

Porphyromonas gingivalis others

Induction of inflammation Oral hygiene

Removal of plaque and calculus gum

reconstruction tetracycline

Necrotizing Ulcerative

Gingivitis and Periodontitis

Polymicrobial community (Treponema

vincentii Prevotella intermedia

Fusobacterium species)

Inflammation Oral hygiene

Debridement of damaged tissue metronidazole

clindamycin

Mumps Mumps virus (genus Paramyxovirus) Droplet contact

Spike-induced syncytium formation

Clinical fluorescent Ag tests ELISA for

Ab

MMR live attenuated

vaccineSupportive

Gastritis and Helicobacter pylori Adhesions ELISA None Antibiotics plus

Gastric Ulcers urease endoscopy

acid suppressors (clarithromycin or

metronidazole plus omeprazole

or bismuth subsalicylate)

DiseaseAcute

Diarrhea

Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

Features

Bacterial Causes

SalmonellaVehicle (food

beverage) fecal-oral

Adhesins endotoxin

Stool culture not

usually necessary

Food hygiene and

personal hygiene

Rehydration no antibiotic

for uncomplicated

disease

Usually Sometimes

Often associated

with chickens reptiles

Shigella Fecal-oral

Endotoxin enterotoxin

shiga toxins in some strains

Stool culture antigen

testing for shiga toxin

Food hygiene and

personal hygiene

TMP-SMZ rehydration Often Often Very low

ID50

Shiga-toxin- producing E coli O157H7 (EHEC)

Vehicle (food beverage) fecal-

oral

Shiga toxins proteins for attachment secretion

effacement

Stool culture antigen

testing for shiga toxin

Avoid live E coli (cook meat and

clean vegetables)

Antibiotics contraindicated supportive

measures

Often UsuallyHemolytic

uremic syndrome

Other E coli (non-shiga-toxin- producing)

Vehicle fecal-oral

Various proteins for attachment secretion

effacement heat-labile

andor heat- stable

exotoxins invasiveness

Stool culture not usually

necessary in absence of blood fever

Food and personal hygiene

Rehydration Sometimes SometimesEIEC ETEC EPEC

Campylobacter Vehicle (food water) fecal-oral

Adhesins exotoxin

induction of autoimmunity

Stool culture not usually necessary dark-field

microscopy

Food and personal hygiene

Rehydration erythromycin

in severe cases

(antibiotic resistance

rising)

Usually NoGuillain-

Barreacute syndrome

Yersinia Vehicle (food Intracellular Cold- Food and None in most Usually Occasionall Severe

water) fecal-oral indirect contact growth enrichment

stool culturepersonal hygiene

cases doxycycline or TMP-SMZ for bacteremia

y abdominal pain

Clostridium difficile

Endogenous (normal biota)

Enterotoxins A and B

Stool culture PCR

ELISA demonstration of toxins

in stool

ndash

Withdrawal of antibiotic in severe cases

metronidazole or vancomycin

SometimesNot

usually mucus

Antibiotic- associated diarrhea

Vibrio choleraeVehicle (water

and some foods) fecal-oral

Cholera toxin (CT)

Clinical diagnosis

microscopic techniques serological detection of

antitoxin

Water hygiene

Rehydration in severe

cases tetracycline

TMP-SMZ

No prominent Rice-water stools

Non-bacterial causes

Cryptosporidium Vehicle (water food) fecal-oral

Intracellular growth

Acid-fast staining ruling out bacteria

Water treatment proper food

handling

None paromomycin

used sometimes

Often Not usually

Resistant to chlorine disinfectio

n

Rotavirus Fecal-oral vehicle fomite ndash Usually not

performedOral live

virus vaccine Rehydration Often No Severe in babies

Other Viruses Fecal-oral vehicle - Usually not performed Hygiene Rehydration Sometimes No

Acute Diarrhea

with Vomiting

(Food Poisoning)

Staphylococcus aureus exotoxin

Vehicle (food)

Heat-stable exotoxin

Usually based on

epidemiological evidence

Proper food handling None Not Usually No

Suspect in foods with high salt or

sugar content

Bacillus cereusHeat-stable toxin heat-labile toxin

Microscopic analysis of

food or stool

Two forms emetic and diarrheal

Clostridium perfringens

Heat-labile toxin

Detection of toxin in stool

Acute abdominal

pain

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

FeaturesChronic Diarrhea Enteroaggregativ

e E coli (EAEC)Vehicle (food

water) fecal-oral

Difficult to distinguish

from other E coli

None or ciprofloxacin No

Sometimes mucus

also

Chronic in the

malnourished

Cyclospora cayetanensis

Fecal-oral vehicle Invasiveness Stool examination

PCR

Washing cooking

food personal hygiene

TMP-SMZ Usually No ndash

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

necessary

Hantavirus

Vehiclemdashairborne virus emitted from

rodents

Ability to induce inflammatory

response

Serology (IgM) PCR identification of antigen in tissue

Avoid mouse habitats and

droppingsSupportive Rapid onset high

mortality rate

SARS-associated coronavirus

Droplet direct contact

Rule out other agents serology

PCRndash Supportive Rapid onset

Histoplasma capsulatum

Vehiclemdashinhalation of

contaminated soil

Survival in phagocytes

Usually serological (rising Ab titers)

Avoid contaminated soil bat bird

droppings

Amphotericin B andor itraconazole

Many infections asymptomatic

Pneumocystis jiroveci Droplet contact ndash Immunofluorescence

Antibiotics given to AIDS patients to prevent this

Trimethoprim- sulfamethoxazole

Vast majority occur in AIDS patients

Nosocomial Pneumonia

Gram-negative and gram-positive

bacteria from upper respiratory tract or stomach

Endogenous (aspiration) Culture of lung fluids

Elevating patientrsquos head preoperative

education care of respiratory

equipment

Broad-spectrum antibiotics

Chapter 22 Infectious diseases affecting the GIT

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Dental CariesStreptococcus mutans Streptococcus sobrinus

othersDirect contact Adhesion acid

production -Oral hygiene

fluoride supplementation

Removal of diseased tooth

material

Periodontitis

Polymicrobial community including

some or all of Tannerella forsythus

Actinobacillus actinomycetemcomitans

Porphyromonas gingivalis others

Induction of inflammation Oral hygiene

Removal of plaque and calculus gum

reconstruction tetracycline

Necrotizing Ulcerative

Gingivitis and Periodontitis

Polymicrobial community (Treponema

vincentii Prevotella intermedia

Fusobacterium species)

Inflammation Oral hygiene

Debridement of damaged tissue metronidazole

clindamycin

Mumps Mumps virus (genus Paramyxovirus) Droplet contact

Spike-induced syncytium formation

Clinical fluorescent Ag tests ELISA for

Ab

MMR live attenuated

vaccineSupportive

Gastritis and Helicobacter pylori Adhesions ELISA None Antibiotics plus

Gastric Ulcers urease endoscopy

acid suppressors (clarithromycin or

metronidazole plus omeprazole

or bismuth subsalicylate)

DiseaseAcute

Diarrhea

Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

Features

Bacterial Causes

SalmonellaVehicle (food

beverage) fecal-oral

Adhesins endotoxin

Stool culture not

usually necessary

Food hygiene and

personal hygiene

Rehydration no antibiotic

for uncomplicated

disease

Usually Sometimes

Often associated

with chickens reptiles

Shigella Fecal-oral

Endotoxin enterotoxin

shiga toxins in some strains

Stool culture antigen

testing for shiga toxin

Food hygiene and

personal hygiene

TMP-SMZ rehydration Often Often Very low

ID50

Shiga-toxin- producing E coli O157H7 (EHEC)

Vehicle (food beverage) fecal-

oral

Shiga toxins proteins for attachment secretion

effacement

Stool culture antigen

testing for shiga toxin

Avoid live E coli (cook meat and

clean vegetables)

Antibiotics contraindicated supportive

measures

Often UsuallyHemolytic

uremic syndrome

Other E coli (non-shiga-toxin- producing)

Vehicle fecal-oral

Various proteins for attachment secretion

effacement heat-labile

andor heat- stable

exotoxins invasiveness

Stool culture not usually

necessary in absence of blood fever

Food and personal hygiene

Rehydration Sometimes SometimesEIEC ETEC EPEC

Campylobacter Vehicle (food water) fecal-oral

Adhesins exotoxin

induction of autoimmunity

Stool culture not usually necessary dark-field

microscopy

Food and personal hygiene

Rehydration erythromycin

in severe cases

(antibiotic resistance

rising)

Usually NoGuillain-

Barreacute syndrome

Yersinia Vehicle (food Intracellular Cold- Food and None in most Usually Occasionall Severe

water) fecal-oral indirect contact growth enrichment

stool culturepersonal hygiene

cases doxycycline or TMP-SMZ for bacteremia

y abdominal pain

Clostridium difficile

Endogenous (normal biota)

Enterotoxins A and B

Stool culture PCR

ELISA demonstration of toxins

in stool

ndash

Withdrawal of antibiotic in severe cases

metronidazole or vancomycin

SometimesNot

usually mucus

Antibiotic- associated diarrhea

Vibrio choleraeVehicle (water

and some foods) fecal-oral

Cholera toxin (CT)

Clinical diagnosis

microscopic techniques serological detection of

antitoxin

Water hygiene

Rehydration in severe

cases tetracycline

TMP-SMZ

No prominent Rice-water stools

Non-bacterial causes

Cryptosporidium Vehicle (water food) fecal-oral

Intracellular growth

Acid-fast staining ruling out bacteria

Water treatment proper food

handling

None paromomycin

used sometimes

Often Not usually

Resistant to chlorine disinfectio

n

Rotavirus Fecal-oral vehicle fomite ndash Usually not

performedOral live

virus vaccine Rehydration Often No Severe in babies

Other Viruses Fecal-oral vehicle - Usually not performed Hygiene Rehydration Sometimes No

Acute Diarrhea

with Vomiting

(Food Poisoning)

Staphylococcus aureus exotoxin

Vehicle (food)

Heat-stable exotoxin

Usually based on

epidemiological evidence

Proper food handling None Not Usually No

Suspect in foods with high salt or

sugar content

Bacillus cereusHeat-stable toxin heat-labile toxin

Microscopic analysis of

food or stool

Two forms emetic and diarrheal

Clostridium perfringens

Heat-labile toxin

Detection of toxin in stool

Acute abdominal

pain

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

FeaturesChronic Diarrhea Enteroaggregativ

e E coli (EAEC)Vehicle (food

water) fecal-oral

Difficult to distinguish

from other E coli

None or ciprofloxacin No

Sometimes mucus

also

Chronic in the

malnourished

Cyclospora cayetanensis

Fecal-oral vehicle Invasiveness Stool examination

PCR

Washing cooking

food personal hygiene

TMP-SMZ Usually No ndash

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

Gastric Ulcers urease endoscopy

acid suppressors (clarithromycin or

metronidazole plus omeprazole

or bismuth subsalicylate)

DiseaseAcute

Diarrhea

Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

Features

Bacterial Causes

SalmonellaVehicle (food

beverage) fecal-oral

Adhesins endotoxin

Stool culture not

usually necessary

Food hygiene and

personal hygiene

Rehydration no antibiotic

for uncomplicated

disease

Usually Sometimes

Often associated

with chickens reptiles

Shigella Fecal-oral

Endotoxin enterotoxin

shiga toxins in some strains

Stool culture antigen

testing for shiga toxin

Food hygiene and

personal hygiene

TMP-SMZ rehydration Often Often Very low

ID50

Shiga-toxin- producing E coli O157H7 (EHEC)

Vehicle (food beverage) fecal-

oral

Shiga toxins proteins for attachment secretion

effacement

Stool culture antigen

testing for shiga toxin

Avoid live E coli (cook meat and

clean vegetables)

Antibiotics contraindicated supportive

measures

Often UsuallyHemolytic

uremic syndrome

Other E coli (non-shiga-toxin- producing)

Vehicle fecal-oral

Various proteins for attachment secretion

effacement heat-labile

andor heat- stable

exotoxins invasiveness

Stool culture not usually

necessary in absence of blood fever

Food and personal hygiene

Rehydration Sometimes SometimesEIEC ETEC EPEC

Campylobacter Vehicle (food water) fecal-oral

Adhesins exotoxin

induction of autoimmunity

Stool culture not usually necessary dark-field

microscopy

Food and personal hygiene

Rehydration erythromycin

in severe cases

(antibiotic resistance

rising)

Usually NoGuillain-

Barreacute syndrome

Yersinia Vehicle (food Intracellular Cold- Food and None in most Usually Occasionall Severe

water) fecal-oral indirect contact growth enrichment

stool culturepersonal hygiene

cases doxycycline or TMP-SMZ for bacteremia

y abdominal pain

Clostridium difficile

Endogenous (normal biota)

Enterotoxins A and B

Stool culture PCR

ELISA demonstration of toxins

in stool

ndash

Withdrawal of antibiotic in severe cases

metronidazole or vancomycin

SometimesNot

usually mucus

Antibiotic- associated diarrhea

Vibrio choleraeVehicle (water

and some foods) fecal-oral

Cholera toxin (CT)

Clinical diagnosis

microscopic techniques serological detection of

antitoxin

Water hygiene

Rehydration in severe

cases tetracycline

TMP-SMZ

No prominent Rice-water stools

Non-bacterial causes

Cryptosporidium Vehicle (water food) fecal-oral

Intracellular growth

Acid-fast staining ruling out bacteria

Water treatment proper food

handling

None paromomycin

used sometimes

Often Not usually

Resistant to chlorine disinfectio

n

Rotavirus Fecal-oral vehicle fomite ndash Usually not

performedOral live

virus vaccine Rehydration Often No Severe in babies

Other Viruses Fecal-oral vehicle - Usually not performed Hygiene Rehydration Sometimes No

Acute Diarrhea

with Vomiting

(Food Poisoning)

Staphylococcus aureus exotoxin

Vehicle (food)

Heat-stable exotoxin

Usually based on

epidemiological evidence

Proper food handling None Not Usually No

Suspect in foods with high salt or

sugar content

Bacillus cereusHeat-stable toxin heat-labile toxin

Microscopic analysis of

food or stool

Two forms emetic and diarrheal

Clostridium perfringens

Heat-labile toxin

Detection of toxin in stool

Acute abdominal

pain

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

FeaturesChronic Diarrhea Enteroaggregativ

e E coli (EAEC)Vehicle (food

water) fecal-oral

Difficult to distinguish

from other E coli

None or ciprofloxacin No

Sometimes mucus

also

Chronic in the

malnourished

Cyclospora cayetanensis

Fecal-oral vehicle Invasiveness Stool examination

PCR

Washing cooking

food personal hygiene

TMP-SMZ Usually No ndash

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

water) fecal-oral indirect contact growth enrichment

stool culturepersonal hygiene

cases doxycycline or TMP-SMZ for bacteremia

y abdominal pain

Clostridium difficile

Endogenous (normal biota)

Enterotoxins A and B

Stool culture PCR

ELISA demonstration of toxins

in stool

ndash

Withdrawal of antibiotic in severe cases

metronidazole or vancomycin

SometimesNot

usually mucus

Antibiotic- associated diarrhea

Vibrio choleraeVehicle (water

and some foods) fecal-oral

Cholera toxin (CT)

Clinical diagnosis

microscopic techniques serological detection of

antitoxin

Water hygiene

Rehydration in severe

cases tetracycline

TMP-SMZ

No prominent Rice-water stools

Non-bacterial causes

Cryptosporidium Vehicle (water food) fecal-oral

Intracellular growth

Acid-fast staining ruling out bacteria

Water treatment proper food

handling

None paromomycin

used sometimes

Often Not usually

Resistant to chlorine disinfectio

n

Rotavirus Fecal-oral vehicle fomite ndash Usually not

performedOral live

virus vaccine Rehydration Often No Severe in babies

Other Viruses Fecal-oral vehicle - Usually not performed Hygiene Rehydration Sometimes No

Acute Diarrhea

with Vomiting

(Food Poisoning)

Staphylococcus aureus exotoxin

Vehicle (food)

Heat-stable exotoxin

Usually based on

epidemiological evidence

Proper food handling None Not Usually No

Suspect in foods with high salt or

sugar content

Bacillus cereusHeat-stable toxin heat-labile toxin

Microscopic analysis of

food or stool

Two forms emetic and diarrheal

Clostridium perfringens

Heat-labile toxin

Detection of toxin in stool

Acute abdominal

pain

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Fever

PresentBlood in

Stool

Distinguishing

FeaturesChronic Diarrhea Enteroaggregativ

e E coli (EAEC)Vehicle (food

water) fecal-oral

Difficult to distinguish

from other E coli

None or ciprofloxacin No

Sometimes mucus

also

Chronic in the

malnourished

Cyclospora cayetanensis

Fecal-oral vehicle Invasiveness Stool examination

PCR

Washing cooking

food personal hygiene

TMP-SMZ Usually No ndash

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

Giardia lambliaVehicle fecal-oral direct and indirect contact

Attachment to intestines

alters mucosa

Stool examination

ELISA

Water hygiene personal hygiene

Quinacrine metronidazole Not usually

No mucus present (greasy

and malodorou

s)

Frequently occurs in

backpackers

campers

Entamoeba histolytica Vehicle fecal-oral

Lytic enzymes induction of apoptosis

invasiveness

Stool examination

ELISA serology

Water hygiene personal hygiene

Iodoquinol plus

metronidazole or

chloroquine Flagyl

Yes Yes

Chronic in the

malnourished

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Long term

consequencesIncubation

Period

Hepatitis

Hepatitis A or E virus Fecal-oral vehicle IgM serology

Hepatitis A vaccine or combined HAVHBV vaccine

Immune globulin None 2ndash7 weeks

Hepatitis B virus

Parenteral (blood contact) direct

contact (especially

sexual) vertical

Latency

Serology (ELISA

radioimmunoassay)

HBV recombinant

vac

Interferon nucleoside

analogs

Chronic infection liver cancer death

1ndash6 months

Hepatitis C virus Parenteral (blood contact) vertical

Core protein suppresses

immune function

Serology

(Pegylated) interferon with

or without ribavirin

Chronic infection and liver disease

very common cancer death

2ndash8 weeks

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Intestinal Distress

Trichuris trichiura(whipworm)

Cycle A vehicle (soil)fecal-oral

Burrowing and invasiveness

Blood count serology egg or worm detection

Hygiene sanitation Mebendazole Humans sole host

Enterobius vermicularis

(pinworm)

Cycle A vehicle (food water) fomites self-inoculation

ndash Adhesive tape method Hygiene Piperazine

pyrantelCommon in United

States

Taenia solium(pork tapeworm)

Cycle C vehicle (pork)mdash also

fecal-oralndash

Blood count serology egg or worm detection

Cook meat avoid pig feces

Praziquantel Niclosamide

Tapeworm intermediate host is

pigsDiphyllobothrium

latum(fish tapeworm)

Cycle C vehicle (seafood)

Vitamin B12 usage

Blood count serology egg or worm detection

Cook meat Praziquantel Niclosamide

Large tapeworm anemia

Hymenolepis nana and H diminuta

Cycle C vehicle (ingesting

insects)ndashndashalso fecal-oral

ndashBlood count

serology egg or worm detection

Hygienic environment Praziquantel Most common

tapeworm infection

Intestinal Distress plus

Migratory Symptoms

Ascaris lumbricoides(intestinal

roundworm)

Cycle A vehicle (soilfecal-oral)

fomites self-inoculation

Induction of hypersensitivity

adult worm migration and

abdominal obstruction

Blood count serology egg or worm detection

Hygiene Alebendazole Roundworm 1 billion persons infected

Necator americanus and Ancylostoma

duodenale (hookworms)

Cycle B vehicle (soil) fomite Sanitation Alebendazole

Penetrates skin serious intestinal

symptoms

Strongyloides stercoralis

(threadworm)

Cycle B vehicle (soil) fomite Sanitation Invermectin or

thiabendazole

Penetrates skin severe for

immunocompromised

Liver and Intestinal Disease

Opisthorchis sinensis Clonorchis sinensis

Cycle D vehicle (fish or

crustaceans) Blood count serology egg or worm detection

Cook food sanitation of

waterPraziquantel Live in bile duct

Fasciola hepaticaCycle D vehicle (water and water

plants)

Sanitation of water Triclabendazole Live in liver and

gallbladder

Liver DiseaseSchistosoma mansoni S japonicum

Cycle D vehicle (contaminated

water)

Antigenic ldquocloakingrdquo

Identification of eggs in feces

scarring of intestines

detected by endoscopy

Avoiding contaminated

vehiclesPraziquantel

Penetrates skin lodges in blood

vessels of intestine damages liver

Muscle and Neurological Symptoms

Trichinella species Vehicle (food)

Serology combined with clinical picture muscle biopsy

Cook meat Mebendazole and steroids

Brain and heart involvement can be

fatal

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

Chapter 23 Infectious Diseases Affecting the Genitourinary tract

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Urinary Tract Infections (Cystitis

Pyelonephritis)

Escherichia coli

Endogenous transfer from GI

tract (opportunism)

Adhesins motility

Often ldquobacterial infectionrdquo

diagnosed on basis of

increased white cells in

urinalysis if culture

performed bacteria may or

may not be identified to species level

Vaccine may be available soon

hygiene practices

Cephalosporin

Staphylococcus saprophyticus Opportunism ndash Hygiene

practices

Ampicillin amoxicillin

trimethoprim-sulfamethoxazole

Proteus mirabilis OpportunismUrease enzyme leads to kidney stone formation

Hygiene practices

Ampicillin or cephalosporins

Kidney stones and severe pain may

ensue

Leptospirosis Leptospira interrogans

Vehiclemdashcontaminated soil or water

Adhesins Invasion proteins

Slide agglutination

test of patientrsquos blood for

antibodies

Strain-specific vaccine

available to limited

populations avoiding

contaminated vehicles

Doxycycline and amoxicillin

Urinary Schistosomiasis

Schistosoma haematobium

Vehicle (contaminated

water)

Antigenic ldquocloakingrdquo induction of

granulomatous response

Identification of eggs in urine

Avoiding contaminated

vehiclesPraziquantel

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

Genital ldquoDischargerdquo Diseases (in Addition to VaginitisVaginosis)

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Vaginitis Vaginosis

Candida albicans Opportunism Wet prep or Gram stain

Topical or oral azole drugs some over-the-counter

drugs

White curdlike discharge

Mixed infection usually including

GardnerellaOpportunism

Visual exam of vagina or clue cells seen in Pap smear or other smear

Metronidazole or clindamycin

Discharge may have fishy smell

Trichomonas vaginalis

Direct contact (STD)

Protozoa seen on Pap smear or Gram stain

Barrier use during

intercourseMetronidazole Discharge may be

greenish

Prostatitis GI tract biota

Endogenous transfer from GI tract otherwise

unknown

Various

Digital rectal exam to examine prostate

culture of urine or semen

NoneAntibiotics muscle

relaxers alpha blockers

Pain in genital area andor back

difficulty urinating

Disease Causative Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishing

Features

Gonorrhea

Effects on fetusEye infections

blindness

Neisseria gonorrhoeae

Direct contact (STD) vertical

Fimbrial adhesions antigenic

variation IgA protease

membrane blebsendotoxin

Gram stain in males rapid tests (PCR ELISA) for

females culture on Thayer-Martin agar

Avoid contact condom use

Many strains resistant to

various antibiotics local and current

guidelines must be consulted

Rare complications include arthritis

meningitis endocarditis

Chlamydia

Effects of FetusEye infections

pneumonia

Chlamydia trachomatis

Intracellular growth resulting

in avoiding immune system

and cytokine release unusual

cell wall preventing

phagolysosome fusion

PCR or ELISA can be followed by cell culture

Azithromycin doxycycline and

follow-up to check for reinfection

More commonly asymptomatic than

gonorrhea

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin

Disease Genital Ulcer

DiseasesCausative

Organism(s)

Most Common

Mode(s) of Transmission

Virulence Factors Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

Syphilis Treponema pallidum

Direct contact and vertical Lipoproteins

Direct tests (immunofluorescence

dark-field microscopy) blood

tests for treponemal and nontreponemal

antibodies PCR

Antibiotic treatment

of all possible contacts avoiding contact

Penicillin G

Three stages of disease plus latent period possibly fatal

Congenital syphilis

Chancroid Haemophilus ducreyi

Direct contact (vertical

transmission not

documented)

Hemolysin (exotoxin) Culture from lesion Avoiding

contactAzithromycin ceftriaxone

No systemic effects None

Herpes Herpes simplex 1 and 2

Direct contact vertical Latency

Clinical presentation PCR Ab tests growth of virus in cell culture

Avoiding contact antivirals

can reduce recurrences

Acyclovir and derivatives

Ranges from asymptomatic

to frequent recurrences

Blindness disseminate

d herpes infection

Disease Wart Disease Causative

Organism(s)

Most Common Mode(s) of

Transmission

Virulence Factors

Culture Diagnosis Prevention Treatment Distinguishin

g FeaturesEffects on

Fetus

HPV Human papillomaviruses

Direct contact (STD)mdashalso

autoinoculation indirect contact

Oncogenes (in the case of malignant types of HPV)

PCR tests for certain HPV types

Vaccine available avoid direct contact prevent cancer by screening

cervix

Warts or precancerous tissue can be

removed virus not treatable

Infection may or may not

result in warts infection may

result in malignancy

May cause laryngeal

warts

Molluscum Contagiosum

Poxvirus sometimes called the molluscum

contagiosum virus (MCV)

Direct contact (STD) also indirect and

autoinoculation

Clinical diagnosis Avoid direct contact

Warts can be removed virus not treatable

Wartlike growths are only known

consequence of infection

Disease Causative Organism(s)

Most Common Mode(s) of Transmission Culture Diagnosis Prevention Treatment

Group B Streptococcus Colonization Group B Streptococcus Vertical Culture of motherrsquos genital

tract Treat mother with penicillin ampicillin