Nematodes, Cestodes, Trematodes

Slackers Facts by Mike Ori

Disclaimer

The information represents my understanding only so errors and omissions are probably rampant. It has not been vetted or reviewed by faculty. The source is our class notes.

The document can mostly be used forward and backward. I tried to mark questionable stuff with (?).

If you want it to look pretty, steal some crayons and go to town.

Finally…

If you’re a gunner, buck up and do your own work.

What are the physical causes of sinusitis?

Obstruction of airflow due to rhinitis or mechanical obstruction

What are the acute sinusitis pathogens

Streptococcus pneumoniaeMoraxella catarrhalis

Haemophilus influenzae - unencapsulated

What is the cause of chronic sinusitis?

Staphylococcus aureusAnaerobes

Enteric gram negatives

What are the complications of sinusitis

Intracranial extension (brain abscess)Orbital infection

Osteomyelitis

What is the most common site of sinusitis

Maxillary sinus

What is the most benign site of sinusitis

Maxillary sinus

What are the agents of otitis media

Streptococcus pneumoniaeMoraxella catarrhalis

Haemophilus Influenzae

What are the agents of otitis externa

Pseudomonas aeriginosaEnterobacteraciae

Fungi

What is the physical cause of otitis externa

Disruption of cerumenElevated pH

Trauma

What is the treatment for otitis media

Systemic antibioticsTypanocentesisTypanostomy

What are the treatments for otitis externa

Remove purulent materialAcidify canal with alcohol and acetic acid

Topical antibiotics if needed

Distinguish otitis media and otitis externa

OM: Usually no pain when pulling pinna. Erythema and bulging seen on tympanic

membrane. Fluid level seen sometimes. No discharge unless tympanum is perforated.

OE: Pain on pinna pull. Discharge often present. Erythema, purulence on external structures.

What are the agents of pharyngotonsilitis

Streptococcus pyogenes (GAS)Respiratory viruses

EnterovirusesEBV

Corynebacterium diphtheriaeNeisseria gonorrhea

What are the general complications of phrayngotonsillitis

AbscessesObstructed airway

What are the agents of Laryngotracheobronchitis

ParainfluenzaOther URI viruses

Mycoplasma pneumoniae

What is the common name for Laryngotracheobronchitis?

Croup

What are the treatments for Laryngotracheobronchitis

Protect airway if threatenedHumidified air

Racemic epinephrineCorticosteroids if severe

What are the agents of epiglottitis

HIB in unvaccinatedStreptococcus pyogenesStaphylococcus aureus

Why precautions must be taken when examining the epiglottis

Airway protection must be available as reaction to the examination may cause sever

constriction of the airway.

What is blepharitis?

Infection of the eyelid margin

What typically causes blepharitis

Staph aureus

What is dacryocystitis

Inflammation of the lacrimal sac

Is conjunctivitis sight threatening

Not usually

What is keratitis

Corneal infection

What are the viral agents of keratitis

HSV-1VZV

Is keratitis sight threatening

Yes

What is uveitis

Infection in the iris, ciliary body, choroid

Is uveitis sight threatening

Yes

What are the agents of retinitis

CMV – in aidsToxoplasmosis

Is retinitis sight threatening

The retina seems important.

What is endophthalmitis

Infection of the eye in general(Requirement fo multiple structure

involvement?)

How are agents introduced in endophthalmitis?

Endogenously from hematogenous spreadExogenously – trauma, surgery

What is the most common organism for endogenous endophthalmitis?

Candida albicans

Is endophthalmitis site threatening

Yes

What is preseptal cellulitis

Infection of the face and eyelid anterior to the orbital septum

Is preseptal cellulitis site threatening

Not usually

What is orbital cellulitis?

Infection of the structure surrounding the eye

Is orbital cellulitis site threatening

Yes. It is also conveniently life threatening. A two-fer.

What fungal infection leads to orbital cellulitis?

Zygormycosis

Distinguish preseptal and orbital cellulitis

Preseptal can look awful in comparison to orbital as the infection is often more obvious.

Eye movement is intact. Eye pain and proptosis are absent.

Orbital: Often misleadingly mild appearance. Pain, decreased motility, proptosis present.

Where does orbital cellulitis arise?

Often in the ethmoid and frontal sinuses

What is impetigo

An infection of the epidermis

What are the agents of impetigo

Streptococcus pyogenesStaphylococcus aureus

Distinguish staph and strep impetigo

As a ballpark, staph is bullous and non-confluent. Strep non bullous and confluent.

What is a non-complicated UTI

One in involving the bladder without retention of urine

Describe the age and gender distribution of UTI?

F > M until later in life.Old > young until death (at which point

incidence is harder to track)

Why are infections in men often “complicated”

BPH leads to urinary retention

What is the leading agent of UTI

Escherichia coli

Why is diabetes a risk for UTI

Increased glucose in urineNeurogenic bladder due to neuropathy

Describe the epidemiology of osteomyelitis

Most cases < 13 yo50% < 5 yo

Why is osteomyelitis more prevalent in children

The metaphyseal plates can form micro necrotic (?) zones in which bacteria can lodge

In what types of bones does osteomyelitis tend to occur

Long bones (ones with metaphyseal growth)It tends not to occur in the flat bones

What are SX of osteomyelitis

Localized pain (possible favoring)Point tenderness to palpation

Heat, redness, swelling develops over timeOften vague complaints with systemic sx like

fever

When do X rays become positive

At best 2 weeks after the infection has started.

What is the best imaging modality

MRI

What imaging modality is used if the site of infection is unclear

Technitium-90 bone scans

What inflammatory markers are used in the dx of osteomyelitis?

ESRCRP

Do you follow ESR or CRP

ESR. Treat until it returns to normal (approximates normal).

Describe the typical osteomyelitis tx duration

Typically tx continues for several weeks.

How is TX of a puncture wound to the foot managed

If osteomyelitis occurs then surgical debridement is necessary. ABX follow for 1

week typically.

How does septic arthritis occur

Most often hematogenousTrauma

Some (16%) extend from osteomyelitis

What are the common sites of septic arthritis

Large joints like knee and elbows

Describe the distribution of septic arthritis

Typically single joint involvedPolyarticular tends toward collagen vascular

diseases

What is unique about the septic arthritis of the hip

Inflammation in the capsule can lead to diminished blood flow and necrosis of the

head of the femur. Recall that the femur has limited vascularization paths.

What is the most common osteomyelitis and septic arthritis agent

Staphylococcus aureus

What is the most common poly arthritis agent in sexually active young people

Neisseria gonorrhea

When is a child a neonate

0-28 days

Describe the humoral immunity of neonates

Transplacental IgG (~23d T ½) IgA from breast milk

What are the TORCHeS organisms

ToxoplasmosisOther (viral)

RubellaCMV

HerpesSyphilis

Describe the role of TORCHeS in clinical practice

It is a hand mnemonic but not a definitive guide

What is the most common congenital infection

CMV

Approximately how many cases of rubella occur in the US

~0

When should a woman of child bearing years be vaccinated for rubella

Preferably before child bearing years to avoid any possibility of congenital rubella due to

reactivation of attenuated rubella. Vaccinate before leaving the hospital after delivery

How does post partum vaccination protect the neonate

It doesn’t. Post partum vaccination protects their future siblings.

What are the sx of congenital rubella

Triad: Heart defects, ocular defects (cataracts), sensorineural deafness, celery stalk long

bones

How can you distinguish prior maternal infection from congenital infection

Maternal ab are IgG. Neonatal are IgM

What are the agents of meningitis in neonated

E. coli, Group B strep, listeria

How is toxoplasmosis infection acquired

1. Cat litter2. Under cooked meat (gato tacos?)

What are the sx of congenital toxoplasmosis

Microcephaly, cerebral calcification, hydrocephaly, chorioretinitis

More in notes

What are the sx of congenital CMV

Organomegally, small for gestational age, purpura, hepatitis, prolonged jaundice, blueberry muffin rash, periventricular

calcification

How many infected children are asymptomatic

90%

What percent of herpes carriers are asymptomatic

75%

What is the mortality rate of congenital herpes

60%

What are the classifications of congenital herpes

1. Skin-eye-membrane – herpetic lesions on skin

2. CNS – Meningoencephalitis without skin manifestations

3. Disseminated – encephalitis, pneumonia

What is the role of acyclovir in congenital herpes prevention

Essentially no role

Which is the preferred delivery route?

C-section if lesions are noted.

When is congenital syphilis acquired

From the 4th month onward

What are the congenital syphilis symptoms

Saber shins, saddle noseRash

More in notes

Describe what tests are required to confirm syphilis

Non-treponemal tests (RPR or VDRL) followed by treponemal tests (FTA, MHA) if positive