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Chapter 18
The Cocci of Medical ImportanceThe Cocci of Medical Importance

General Characteristics of the Staphylococci
Nonmotile, gram-Nonmotile, gram-positive cocci positive cocci arranged in irregular arranged in irregular clustersclusters
Facultative anaerobesFacultative anaerobes FermentativeFermentative Salt-tolerantSalt-tolerant Catalase-positiveCatalase-positive Pyogenic if stimulate Pyogenic if stimulate
pus formationpus formation


Staphylococcus aureus Skin infections:Skin infections:
Local abscess occurs at site Local abscess occurs at site of invasion of hair follicle, of invasion of hair follicle, glandgland
Manifestations:Manifestations: Folliculitis – Folliculitis –
inflammation of hair inflammation of hair folliclefollicle
Furuncle - boilFuruncle - boil Carbuncle – deeper Carbuncle – deeper
lesion aggregation of a lesion aggregation of a cluster of furunclescluster of furuncles
Bullous impetigo – Bullous impetigo – epidermal swellings that epidermal swellings that peel awaypeel away

Staphylococcus aureus
Toxic disease:Toxic disease: Food intoxication due Food intoxication due
to enterotoxinto enterotoxin Staphylococcal scaled Staphylococcal scaled
skin syndrome skin syndrome Toxic shock syndromeToxic shock syndrome
Toxemia in women Toxemia in women due to infection of due to infection of vaginavagina
Associated with Associated with tampon usagetampon usage

Staphylococcus aureus Osteomyelitis Osteomyelitis
Bacteria spread in the circulation from some other infection Bacteria spread in the circulation from some other infection site, enter the artery, and lodge in the small vessels in bony site, enter the artery, and lodge in the small vessels in bony pockets of the marrowpockets of the marrow
Growth of the cells causes inflammation and damage that Growth of the cells causes inflammation and damage that manifest as swelling and necrosismanifest as swelling and necrosis

Principal coagulase-Negative Staphylococci
Staphylococcus saprophyticusStaphylococcus saprophyticus Urinary pathogenUrinary pathogen
Staphylococcus epidermidisStaphylococcus epidermidis Normal resident of skin and folliclesNormal resident of skin and follicles An opportunistAn opportunist One of the most common causes of nosocomial One of the most common causes of nosocomial
infectionsinfections Mainly in surgical patients with indwelling Mainly in surgical patients with indwelling
medical devices or implantsmedical devices or implants

Treatment for Staph infections
S. aureusS. aureus has multiple resistance to antibiotics, has multiple resistance to antibiotics, especially penicillin, ampicillin, and methicillinespecially penicillin, ampicillin, and methicillin
Abscesses require debridement and removal of pusAbscesses require debridement and removal of pus StaphylococciStaphylococci have extreme resistance to harsh have extreme resistance to harsh
environmental conditionsenvironmental conditions Staph infections are frequently complicated by Staph infections are frequently complicated by
their tendency to form biofilms on medical their tendency to form biofilms on medical devicesdevices

General Characteristics of the Streptococci Genera
Gram-positive cocci in Gram-positive cocci in chains of various chains of various lengthslengths
NonmotileNonmotile Non-spore formingNon-spore forming EncapsulatedEncapsulated Catalase negativeCatalase negative

Streptococcus Genus - Genus - StreptococcusStreptococcus
Streptococcus pyogenesStreptococcus pyogenes (Group A streptococci) (Group A streptococci) Streptococcus agalactiaeStreptococcus agalactiae (Group B streptococci) (Group B streptococci) Group D streptococciGroup D streptococci
EnterococciEnterococci• Enterococcus (Streptococcus) faecalisEnterococcus (Streptococcus) faecalis• Enterococcus (Streptococcus) faeciumEnterococcus (Streptococcus) faecium• Enterococcus (Streptococcus) duransEnterococcus (Streptococcus) durans
Non-enterococcalNon-enterococcal Group D Group D• Streptococcus bovisStreptococcus bovis• Streptococcus equinusStreptococcus equinus
Viridans streptococciViridans streptococci Streptococcus pneumoniaeStreptococcus pneumoniae

Classification scheme for streptococci Based on hemolytic propertiesBased on hemolytic properties
Types of hemolysisTypes of hemolysis Beta (clear, complete)Beta (clear, complete) Alpha (green, incomplete) - Alpha (green, incomplete) -
also called viridans; green also called viridans; green color = production of a color = production of a hemoglobin reducing agenthemoglobin reducing agent
Alpha prime = large zone of Alpha prime = large zone of alpha hemolysis encircled by alpha hemolysis encircled by a narrow zone of betaa narrow zone of beta
Gamma (none) - commonly Gamma (none) - commonly called non-hemolytic strepcalled non-hemolytic strep
Reasons for being unreliable Reasons for being unreliable criteriacriteria
Some strains become Some strains become hemolytic after 24 hrs hemolytic after 24 hrs incubationincubation
Type hemolysis cell Type hemolysis cell dependent - sheep blood used dependent - sheep blood used in U.S.in U.S.

Classification scheme for streptococci Based on antigenic propertiesBased on antigenic properties
Lancefield grouping = carbohydrates in cell wall (C groupLancefield grouping = carbohydrates in cell wall (C group carbohydrates)carbohydrates) Found in all strep except viridansFound in all strep except viridans Classifies into 13 groups (designated A-O)Classifies into 13 groups (designated A-O) Methods for detection have been time consuming andMethods for detection have been time consuming and difficult - new difficult - new
easier methods now availableeasier methods now available Definitive method of classificationDefinitive method of classification Most common groups encountered = A, B, C, D, F, and GMost common groups encountered = A, B, C, D, F, and G

Virulence Factors for S. pyogenes (Group A streptococci)
AnatomicalAnatomical M protein - associated M protein - associated
with pilli and with pilli and lipoteichoic acid; play lipoteichoic acid; play role in attachment; role in attachment; over 70 different types over 70 different types known; immunity to known; immunity to streptococcal infection streptococcal infection M type specificM type specific
Capsule - composed of Capsule - composed of hyaluronic acid; hyaluronic acid; antiphagocyticantiphagocytic

Virulence Factors for S. pyogenes (Group A streptococci)
Toxins and other biologically active extracellular productsToxins and other biologically active extracellular products Hemolysins - streptolysinsHemolysins - streptolysins
Streptolysin O - oxygen labileStreptolysin O - oxygen labile
• Binds cholesterol in cell membranes of rbc'sBinds cholesterol in cell membranes of rbc's wbc's, and wbc's, and platelets - lysis causes degranulation of wbc's with platelets - lysis causes degranulation of wbc's with release of hydrolytic enzymes - further damages tissuerelease of hydrolytic enzymes - further damages tissue
• Reversibly inactivated by oxygen - demonstrated in vitro Reversibly inactivated by oxygen - demonstrated in vitro in deep (anaerobic) coloniesin deep (anaerobic) colonies
• Antigenic - antibodies = antistreptolysin OAntigenic - antibodies = antistreptolysin O (ASO)(ASO) Streptolysin S - oxygen stableStreptolysin S - oxygen stable
• Mostly cell boundMostly cell bound
• No neutralizing Ab yet describedNo neutralizing Ab yet described rbc's; inhibit rbc's; inhibit chemotaxis & phagocytosischemotaxis & phagocytosis

Virulence Factors for S. pyogenes (Group A streptococci)
Deoxyribonucleases (DNases) - degrade DNA and Deoxyribonucleases (DNases) - degrade DNA and to a lesser extent RNA in pus - facilitates spread of to a lesser extent RNA in pus - facilitates spread of infectioninfection
Hyaluronidase - spreading factor; sometimes find Hyaluronidase - spreading factor; sometimes find both hyaluronic capsules and hyaluronidase in both hyaluronic capsules and hyaluronidase in same organismsame organism
Erythrogenic toxin (also called streptococcal Erythrogenic toxin (also called streptococcal pyrogenic exotoxins)pyrogenic exotoxins) Responsible for rash of scarlet fever and appear Responsible for rash of scarlet fever and appear
toto play role in toxic-like syndromeplay role in toxic-like syndrome

Virulence Factors for S. agalactiae (Group B streptococci)
Anatomical - capsule; antigenic and Anatomical - capsule; antigenic and antiphagocyticantiphagocytic

Virulence Factors for S. pneumoniae
Anatomical - capsule is polysaccharide; 84 Anatomical - capsule is polysaccharide; 84 different types known;different types known; some types cross-some types cross-react with polysaccharides produced by react with polysaccharides produced by otherother bacteria and with human blood group bacteria and with human blood group B isoantigen; antiphagocyticB isoantigen; antiphagocytic

S. pyogenes (Group A streptococci) Diseases
Suppurative infections - invasive properties related Suppurative infections - invasive properties related to capsule and M proteins; virulence with to capsule and M proteins; virulence with streptolysins (pyogenic)streptolysins (pyogenic) Pharyngitis - common in children; usually self-Pharyngitis - common in children; usually self-
limiting; canlimiting; can lead to non-suppurative sequelaelead to non-suppurative sequelae Puerperal infection (childbed fever) - infection of Puerperal infection (childbed fever) - infection of
endometrium at or near delivery; life threatening; endometrium at or near delivery; life threatening; may spread to other sites in bodymay spread to other sites in body

S. pyogenes (Group A streptococci) Diseases
Impetigo (Indian Impetigo (Indian fire) - localized skin fire) - localized skin infection; common infection; common inin childrenchildren
Erysipelas - Erysipelas - involves skin and involves skin and subcutaneous tissue; subcutaneous tissue; spreadsspreads rapidlyrapidly

S. pyogenes (Group A streptococci) Diseases
Toxic diseaseToxic disease Scarlet feverScarlet fever
Caused by infection with erythrogenic Caused by infection with erythrogenic strains in sensitive individualsstrains in sensitive individuals
Localized infection with systemic Localized infection with systemic manifestationsmanifestations
Characterized by red rash over most of Characterized by red rash over most of body (strawberry tongue)body (strawberry tongue)

S. pyogenes (Group A streptococci) Diseases
Delayed Non-Suppurative Delayed Non-Suppurative ComplicationsComplications Acute rheumatic fever (ARF)Acute rheumatic fever (ARF)
Symptoms - fever and Symptoms - fever and inflammation of joints, heart,inflammation of joints, heart, subcutaneous tissue and CNS subcutaneous tissue and CNS beginning 1-5 weeksbeginning 1-5 weeks after after Group A pharyngitis; may Group A pharyngitis; may cause serious and permanent cause serious and permanent damage to heartdamage to heart
Follows only respiratory strept. Follows only respiratory strept. infection infection
Can be prevented by treatment Can be prevented by treatment of pharyngitis within 9 days of of pharyngitis within 9 days of onset of infectiononset of infection

S. pyogenes (Group A streptococci) Diseases
Delayed Non-Suppurative ComplicationsDelayed Non-Suppurative Complications Acute glomerulonephritis (AGN)Acute glomerulonephritis (AGN)
Symptoms - edema, hypertension, hematuria & Symptoms - edema, hypertension, hematuria & proteinuria; usually benign but may lead to renal proteinuria; usually benign but may lead to renal failure and deathfailure and death
Follows either respiratory or cutaneous infections;Follows either respiratory or cutaneous infections; requires infection with certain M type strains calledrequires infection with certain M type strains called nephritogenicnephritogenic
Typically occurs 6-10 days after onset of Typically occurs 6-10 days after onset of pharyngitis or 14-21 days after cutaneous infection; pharyngitis or 14-21 days after cutaneous infection; not prevented by rapid therapynot prevented by rapid therapy

S. agalactiae (Group B streptococcal) Diseases
Infants - leading cause of pneumonia, sepsis and Infants - leading cause of pneumonia, sepsis and meningitis duringmeningitis during first 2 months of lifefirst 2 months of life Most develop in immediate perinatal period (within 7 Most develop in immediate perinatal period (within 7
daysdays of birth)of birth) Most result from contamination from female genital Most result from contamination from female genital
tract where organism is normal in ~ one-third tract where organism is normal in ~ one-third womenwomen
Degree of vaginal & cervical colonization in mother Degree of vaginal & cervical colonization in mother directly related to likelihood & severity of disease in directly related to likelihood & severity of disease in infantinfant

S. agalactiae (Group B streptococcal) Diseases
Children and adultsChildren and adults Infections associated with gynecologic Infections associated with gynecologic
manipulation/surgerymanipulation/surgery Rare cause of upper respiratory Rare cause of upper respiratory
infections, meningitis, bacteremia and infections, meningitis, bacteremia and endocarditisendocarditis

Group D (enterococci and non-enterococcal strains) Diseases
Urinary tract infections - associated with Urinary tract infections - associated with manipulations, malignancies, biliary tract disease manipulations, malignancies, biliary tract disease & GI disorders& GI disorders
Wound and soft tissue infectionsWound and soft tissue infections Endocarditis - bacteremia associated with lon-term Endocarditis - bacteremia associated with lon-term
indwellingindwelling intravenous cathetersintravenous catheters S. bovisS. bovis (non-enterococcal sp.) linked to (non-enterococcal sp.) linked to
neoplasms of GI tract, esp. colon; recovery from neoplasms of GI tract, esp. colon; recovery from adult blood cultures should prompt GIadult blood cultures should prompt GI tract tract evaluationevaluation

Viridans streptococci Diseases Sub-acute bacterial Sub-acute bacterial
endocarditis (SBE)endocarditis (SBE) Organism normally Organism normally
present in oral cavity present in oral cavity showered into blood = showered into blood = transient bacteremiatransient bacteremia
Presence of previously Presence of previously damaged heart valves = damaged heart valves = SBESBE
May be fatalMay be fatal Some species associated Some species associated
with brain abscesses, with brain abscesses, meningitis, liver abscesses & meningitis, liver abscesses & appendicitisappendicitis

S. pneumoniae Diseases PneumoniaPneumonia
Most common cause of Most common cause of community-acquired community-acquired pneumoniapneumonia
Organisms part of normal Organisms part of normal upper respiratory tract – upper respiratory tract – beginsbegins with aspirationwith aspiration
More common in persons More common in persons with chronic lung with chronic lung conditions including conditions including smokers, defects in smokers, defects in phagocyte function or phagocyte function or humoral immunity or those humoral immunity or those with ethanol intoxicationwith ethanol intoxication

The Course of Bacterial Pneumonia
As the pneumococcus As the pneumococcus traces a pathway down the traces a pathway down the respiratory tree, it respiratory tree, it provokes intense provokes intense inflammation and exudate inflammation and exudate formationformation
The blocking of the The blocking of the bronchioles and alveoli by bronchioles and alveoli by consolidation of consolidation of inflammatory cells and inflammatory cells and product is shownproduct is shown

S. pneumoniae Diseases
MeningitisMeningitis One of three leading causes of meningitisOne of three leading causes of meningitis More common in later lifeMore common in later life Signs and symptoms similar in all forms Signs and symptoms similar in all forms
of meningitisof meningitis Upper respiratory infections - sinusitis, Upper respiratory infections - sinusitis,
otitis mediaotitis media Other - endocarditis, arthritis, peritonitisOther - endocarditis, arthritis, peritonitis

S. pneumoniae Diseases
Upper respiratory Upper respiratory infections - sinusitis, infections - sinusitis, otitis mediaotitis media
The direct connection The direct connection between the pharynx between the pharynx and middle ear via the and middle ear via the eustachian tube makes eustachian tube makes this possiblethis possible

Epidemiology of Streptococcus
Natural habitatNatural habitat Group A, pneumococci and viridans strept - upper respiratoryGroup A, pneumococci and viridans strept - upper respiratory
tract of humanstract of humans Group A, B, and D - vaginalGroup A, B, and D - vaginal Group B and D – intestineGroup B and D – intestine
TransmissionTransmission Direct contact with mucosa or secretionsDirect contact with mucosa or secretions Aerosols - droplet produced by coughing, sneezing, talkingAerosols - droplet produced by coughing, sneezing, talking Indirect - fomites (shared inanimate objects)Indirect - fomites (shared inanimate objects) Insects, esp. FliesInsects, esp. Flies Food-borneFood-borne

Epidemiology of Streptococcus
Control and preventionControl and prevention Hand washingHand washing C section (Group B)C section (Group B) Vaccines - M protein antigens for Group A Vaccines - M protein antigens for Group A
strep & capsular antigens for pneumococcistrep & capsular antigens for pneumococci Treatment - penicillin (drug of choice) except Treatment - penicillin (drug of choice) except
enterococci which require combination of enterococci which require combination of penicillin or vancomycin with an aminoglycosidepenicillin or vancomycin with an aminoglycoside

General Characteristics of the Neisseria Genera
Gram-negative diplococci Gram-negative diplococci that have capsules and that have capsules and fimbriaefimbriae
Oxidase-positiveOxidase-positive Non-spore formingNon-spore forming NonmotileNonmotile FastidiousFastidious Do not survive long in the Do not survive long in the
environmentenvironment Common residents of Common residents of
mucous membranesmucous membranes

Neisseria Family
AcinetobacterAcinetobacter - only oxidase negative genera - only oxidase negative genera KingellaKingella - only catalase negative genera - only catalase negative genera MoraxellaMoraxella including including M. catarrhalisM. catarrhalis (former called (former called
Branhamella catarrhalisBranhamella catarrhalis)) NeisseriaNeisseria
N. gonorrhoeaeN. gonorrhoeae (common name = gonococcus or GC) (common name = gonococcus or GC) N. meningitidisN. meningitidis (common name = meningococcus) (common name = meningococcus) N. lactamicaN. lactamica Other Other NeisseriaNeisseria = = N. sicca, N. subflava, N. mucosa, N. N. sicca, N. subflava, N. mucosa, N.
flavescens, N. cinerea, flavescens, N. cinerea, andand N. elongata N. elongata

Virulence Factors for N. gonorrhoeae
AnatomicalAnatomical Pili - mediate adherence; antigenically variablePili - mediate adherence; antigenically variable Endotoxin - mediates local and systemic damage Endotoxin - mediates local and systemic damage
including petechiae and DICincluding petechiae and DIC Biologically active extracellular productsBiologically active extracellular products
IgA1 protease - role unknown; may facilitate IgA1 protease - role unknown; may facilitate invasioninvasion
Beta lactamase - destroys penicillin; not found in Beta lactamase - destroys penicillin; not found in all strainsall strains

Virulence Factors for N. meningitidis
AnatomicalAnatomical Pili - mediate adherence; selective for non-Pili - mediate adherence; selective for non-
ciliated columnar epitheliumciliated columnar epithelium Capsules - polysaccharide; antigenic; Capsules - polysaccharide; antigenic;
subdivides meningococci into 9 groups subdivides meningococci into 9 groups (epidemic groups = A, B, and C); (epidemic groups = A, B, and C); antiphagocyticantiphagocytic
Endotoxin - mediates tissue damage; causes Endotoxin - mediates tissue damage; causes petechiae and DICpetechiae and DIC

Clinical Manifestations of N. gonorrhoeae
PathogenesisPathogenesis Attach via pili to epithelial cells on contact, Attach via pili to epithelial cells on contact,
enter and multiply within cells (intracellular enter and multiply within cells (intracellular parasites)parasites)
Spread via direct extension; cause acute, Spread via direct extension; cause acute, localized inflammatory response - further localized inflammatory response - further spread facilitated by pilus-mediated attachment spread facilitated by pilus-mediated attachment to sperm; may also spread hematogenouslyto sperm; may also spread hematogenously

Clinical Manifestations of N. gonorrhoeae Genital infections are of epidemic proportions (approx. 1M Genital infections are of epidemic proportions (approx. 1M
cases/yr. in US)cases/yr. in US) Genital infections (gonorrhea) - commonly called “clap”; Genital infections (gonorrhea) - commonly called “clap”;
occurs after genital intercourseoccurs after genital intercourse Different for man v. womanDifferent for man v. woman

Clinical Manifestations of N. gonorrhoeae
Genital Gonorrhea in Genital Gonorrhea in the Malethe Male Primary site - urethraPrimary site - urethra Symptoms begin 1-Symptoms begin 1-
14 days post 14 days post infection; purulent infection; purulent urethral discharge urethral discharge and dysuria; rarely and dysuria; rarely mild or absentmild or absent
Local extension Local extension uncommon but uncommon but possible leading to possible leading to prostatitis & prostatitis & epididymitisepididymitis

Clinical Manifestations of N. gonorrhoeae
Genital Gonorrhea in the Genital Gonorrhea in the FemaleFemale Primary site - endocervixPrimary site - endocervix Symptoms begin 2-7 days Symptoms begin 2-7 days
post infection; vaginal post infection; vaginal discharge, dysuria, discharge, dysuria, abdominal pain and abdominal pain and menstrual abnormalities; menstrual abnormalities; usually mild or absentusually mild or absent
Local extension common Local extension common leading to pelvic leading to pelvic inflammatory disease inflammatory disease (PID) and sterility(PID) and sterility

Clinical Manifestations of N. gonorrhoeae
Rectal infections - occurs after rectal Rectal infections - occurs after rectal intercourse or after contamination of rectal intercourse or after contamination of rectal area with infected vaginal secretions in area with infected vaginal secretions in females; symptoms may manifest as rectal females; symptoms may manifest as rectal bleeding but usually asymptomaticbleeding but usually asymptomatic
Pharyngeal infections - follows oral/genital Pharyngeal infections - follows oral/genital sex; generally asymptomatic but may sex; generally asymptomatic but may produce sore throat and cervical adenitisproduce sore throat and cervical adenitis

Clinical Manifestations of N. gonorrhoeae
Pelvic inflammatory disease (PID)Pelvic inflammatory disease (PID) Local extension of cervical infection; causes Local extension of cervical infection; causes
endometritis, salpingitis & peritonitisendometritis, salpingitis & peritonitis Symptoms = fever and lower abdominal pain Symptoms = fever and lower abdominal pain Sterility caused by scarring of fallopian tubes – may Sterility caused by scarring of fallopian tubes – may
follow single attack; occurs in up to 20% of women with follow single attack; occurs in up to 20% of women with gonorrheagonorrhea
Disseminated gonococcal infections (DGI)Disseminated gonococcal infections (DGI) Follows hematogenous spread from any site Follows hematogenous spread from any site Symptoms = rash (petechial, maculopapular or pustular), Symptoms = rash (petechial, maculopapular or pustular),
arthritis (large joints), endocarditis, and meningitisarthritis (large joints), endocarditis, and meningitis

Clinical Manifestations of N. gonorrhoeae
Conjunctivitis and ophthalmia neonatorum (ON)Conjunctivitis and ophthalmia neonatorum (ON) May occur at any age by contamination of May occur at any age by contamination of
conjunctiva (ON - of newborn during vaginal conjunctiva (ON - of newborn during vaginal birth from infected mother)birth from infected mother)
Symptoms = severe, acute, purulent Symptoms = severe, acute, purulent conjunctivitis; may lead to blindnessconjunctivitis; may lead to blindness
Common cause of blindness in newborns until Common cause of blindness in newborns until use of silver nitrate or penicillin drops instituted use of silver nitrate or penicillin drops instituted as standard treatment for all newborns as standard treatment for all newborns

N. Meningitidis - also called meningococcus Pathogenesis Pathogenesis
Pili mediate attachment of Pili mediate attachment of organisms to non-ciliated organisms to non-ciliated columnar epithelial cells in columnar epithelial cells in nasopharynx where organisms nasopharynx where organisms multiply and spread by direct multiply and spread by direct extension to adjacent cells -extension to adjacent cells -may damage adjacent ciliated may damage adjacent ciliated cells via release of endotoxincells via release of endotoxin
Enter blood via cervical lymph Enter blood via cervical lymph nodes (meningococcemia) to nodes (meningococcemia) to spread hematogenously spread hematogenously throughout the bodythroughout the body
Cross blood-brain barrier and Cross blood-brain barrier and infect meningesinfect meninges

Clinical Manifestations of N. meningitidis
Meningitis (acute, epidemic meningitis)Meningitis (acute, epidemic meningitis) Most common form of meningococcal infectionMost common form of meningococcal infection Peak incidence = 6 months - 2 years and 5-18 Peak incidence = 6 months - 2 years and 5-18
yrs. (common in military recruits) yrs. (common in military recruits) Symptoms = fever, headache, stiff neck, Symptoms = fever, headache, stiff neck,
paralysis; coma and death occurs if not treatedparalysis; coma and death occurs if not treated If present, petechial rash diagnostic for MCIf present, petechial rash diagnostic for MC

Clinical Manifestations of N. meningitidis
Meningococcemia and petechial Meningococcemia and petechial rashrash Occurs with or without Occurs with or without
meningitismeningitis Rash caused by Rash caused by
thrombocytopenia and thrombocytopenia and endotoxemia may also be endotoxemia may also be accompanied by DICaccompanied by DIC
Waterhouse-Friderichsen syndromeWaterhouse-Friderichsen syndrome Occurs in fulminant Occurs in fulminant
meningococcemiameningococcemia Characterized by DIC with Characterized by DIC with
bilateral hemorrhagic bilateral hemorrhagic destruction of adrenal glands destruction of adrenal glands due to endotoxemiadue to endotoxemia

Clinical Manifestations of M. Catarrhalis
Occurs in individuals with compromised Occurs in individuals with compromised respiratory tract function; respiratory tract function;
Normally part of upper respiratory floraNormally part of upper respiratory flora Lower respiratory infection - acute Lower respiratory infection - acute
bronchitis and pneumonia bronchitis and pneumonia Also cause on rare occasion endocarditis, Also cause on rare occasion endocarditis,
meningitis, conjunctivitis and septicemiameningitis, conjunctivitis and septicemia Other = Otitis media and maxillary sinusitis Other = Otitis media and maxillary sinusitis

Epidemiology of Neisseria
Habitat - strict human parasites; mucous membranesHabitat - strict human parasites; mucous membranes M. CatarrhalisM. Catarrhalis and all and all NeisseriaNeisseria except except N. gonorrhoeaeN. gonorrhoeae
part of normal flora - high normal carrier ratepart of normal flora - high normal carrier rate All except All except N. gonorrhoeaeN. gonorrhoeae norm in upper respiratory tract norm in upper respiratory tract
Routes of transmissionRoutes of transmission N. gonorrhoeaeN. gonorrhoeae - most by direct venereal (sexual) routes; - most by direct venereal (sexual) routes;
rarely involves fomitesrarely involves fomites N. meningitidisN. meningitidis - respiratory droplets; requires close - respiratory droplets; requires close
contact and a susceptible (non-immune) hostcontact and a susceptible (non-immune) host M. catarrhalisM. catarrhalis - endogenous; droplet - endogenous; droplet

Epidemiology of Neisseria Prevention and ControlPrevention and Control
N. gonorrhoeaeN. gonorrhoeae - “safe” sex; case-contact - “safe” sex; case-contact tracking/treatmenttracking/treatment
N. meningitidisN. meningitidis - chemoprophylaxis (rifampin) if - chemoprophylaxis (rifampin) if exposed; vaccines to susceptible individuals; vaccines exposed; vaccines to susceptible individuals; vaccines directed against polysaccharide capsular antigens directed against polysaccharide capsular antigens available - used primarily in military recruitsavailable - used primarily in military recruits
TreatmentTreatment N. gonorrhoeaeN. gonorrhoeae - penicillin for non-resistant strains; - penicillin for non-resistant strains;
spectinomycin or ceftriaxone for PPNG (penicillinase spectinomycin or ceftriaxone for PPNG (penicillinase producing producing Neisseria gonorrhoeaeNeisseria gonorrhoeae))
N. meningitidisN. meningitidis - penicillin (ampicillin) - penicillin (ampicillin) M. catarrhalisM. catarrhalis - most strains produce penicillinase; may - most strains produce penicillinase; may
use erythromycin or tetracyclineuse erythromycin or tetracycline