When is toxoplasmosis typically transmitted to a fetus (under what conditions)?

When the mother has a primary infection

Immunosuppressed patients sometimes experience reactivation of toxoplasmosis infections. Can congenital toxoplasmosis develop during reactivations?

Yes

Transmission of toxoplasmosis is most likely in what part of pregnancy?

Late

(14 % first trimester, 60 % third trimester)

Congenital toxoplasmosis is generally most severe when acquired during what trimester?

The first

(the earlier the infection, the greater the effect, in general)

Is congenital toxoplasmosis usually evident at birth?

No – at least 75 % are asymptomatic

What two organs does congenital toxoplasmosis prefer?

Eyes & CNS

Is congenital toxoplasmosis more or less common in preemies?

More

What is the “classic triad” of symptomatic congenital toxoplasmosis?

1. Obstructive hydrocephalus

2. Intracranial calcifications

3. Chorioretinitis (white dots on retinal exam)

What is the main natural reservoir for toxoplasmosis?

Cats

In addition to cat feces, where else might someone encounter toxoplasmosis?

1. Undercooked meat (especially pork) and eggs

2. Unpasteurized milk

3. Transfusions (of blood products including WBCs)

When an adult is infected with toxoplasmosis, how do they present?

(2 possibilities)

1. Usually they don’t present – it’s subclinical

2. Nonspecific illness with fever, lymphadenopathy, +/− rash

What is the most typical outcome of congenital toxoplasmosis infection

Visual impairment & learning disabilities (presenting months to years later)

In addition to nonspecific findings such as lymphadenopathy, fever, and hepatosplenomegaly, what other findings/signs are likely in infants with obvious congenital toxoplasmosis?

(4 categories)

1. Chorioretinitis

2. Seizures

3. Microcephaly or hydrocephaly

4. Eye abnormalities (cataracts, microphthalmos, optic atrophy, glaucoma, etc.)

What tests should be done to confirm suspected congenital toxoplasmosis?

(3)

1. Serum (for IgM)

2. CSF

3. Head CT

(for calcifications)

If a neonate has congenital toxoplasmosis, what do you expect to see in the CSF?

(3)

1. High protein

2. Pleocytosis

3. Xanthochromia

How is congenital toxoplasmosis usually treated? (asymptomatic)

12 months of: pyrimethamine  +  sulfadiazine  +  leucovorin

(some use spiramycin in the last 6 months)

How long should an apparently healthy infant be treated for congenital toxo if his/her mother is known to have contracted the disease during pregnancy?

4 weeks

(then confirm the diagnosis)

If a pregnant woman is known to be toxo infected (primary or recurrent), should she be treated?

Yes –

Reduces risk of fetal infection or loss

What anti-inflammatory is sometimes given to infants with symptomatic toxoplasmosis?

Steroids

During treatment, infants with toxo must be monitored for medication side effects with what three tests?

How often?

1. CBC

2. Platelets

3. UA

• Every week

During what part of pregnancy is rubella infection most likely to affect a fetus?

U shaped probability –

either early or late in gestation is bad

What kind of virus is rubella?

RNA

What is the natural reservoir for rubella?

Non-immunized humans only

If a child seems to have mononucleosis, but is negative for EBV, what is a likely cause?

CMV

What are latex agglutination tests used for?

(same infectious diseases as CIE or counter–immunoelectrophoresis testing)

Partially treated infections

(looks for bacterial cell wall components)

What organisms can a latex agglutination test identify?

Grp B strep

H . flu

N . meningitidis

Strep pneumoniae

Which patients are most likely to have false-positive latex agglutination tests?

(2)

Hib vaccinated

&

Those infected with certain E. coli types

What medications can be used to eliminate the carrier state of diphtheria?

Erythromycin or

penicillin

Diphtheria vaccination protects a patient from what aspect of the infection?

The carrier state

Although Pneumocystis carinii/jiroveci (PCP) is an opportunistic infection, it is often seen in children without a known history of immunocompromise. Why?

It tends to be the first opportunistic infection

If a child is known to be at risk for PCP, what medication should be started?

Bactrim ^®

(generic is TMP/SMX)

In an immunocompromised child with fever & neutropenia, what general categories of antimicrobials will your initial management definitely include?

1. Gram+ antibiotic

2. Gram− antibiotic (e.g., aminoglycoside)

3. Antipseudomonal

If a child presents with atypical tuberculosis, what underlying problem should you consider?

Immunocompromise

Abdominal pain or obstruction  +  exotic foreign travel or foreign birth  =  what diagnosis?

Ascaris lumbricoides

(at least think of it)

How is ascaris infection treated?

Albendazole, mebendazole, or ivermectin

“Staccato cough” – first 2 months of life – no fever – tachypnea =

Chlamydial pneumonia

What is the buzzword for Chlamydia pneumoniae infection on micro examination?

Intracytoplasmic inclusion bodies

How is chlamydial pneumonia treated?

Erythromycin

(or other macrolide)

Can chlamydial pneumonia be seen in adolescents/adults?

Yes

(it is another atypical along with mycoplasma)

How is chlamydial pneumonia definitely diagnosed?

Immunofluorescent antibodies

Imagine fluorescent pink “Chlams” glowing in the dark

What is the name of the only rickettsial disease that causes pneumonia but no rash?

Q fever

A patient who presents with headache and a rash that moves inward from the extremities may have what serious infectious disease?

RMSF (Rocky Mountain spotted fever)

How is the rash of Rocky Mountain spotted fever described?

Maculopapular –

•  Starts on extremities

•  Becomes petechial/purpuric

What is the treatment of choice for RMSF (Rocky Mountain spotted fever)?

Doxycycline (regardless of age!)

Why is it alright to use doxycycline in a child less than 9 years old if you are treating RMSF?

(Cost-benefit)

1. Risk of death vs. risk of tooth staining

2. Tooth staining is unlikely with short-term use anyway

What is a good way to remember the rash pattern for RMSF?

If you were rock climbing in the Rockies, you would probably get some petechiae on your hands & feet

In case of doxycycline allergy, what alternative medication can be used to treat RMSF?

Chloramphenicol

How can CMV be transmitted to a neonate?

(4)

1. Transplacentally with maternal infection (usually primary infection)

2. At delivery with maternal cervical colonization

3. Breast milk

4. Blood transfusion

If a pregnant mother contracts CMV, is she likely to notice the infection?

Usually noticed, but not always reported (nonspecific malaise-type illness)

What percentage of asymptomatically CMV-infected neonates develops serious visual, hearing, or cognitive impairments by age 2 years?

About 10 %

What is “classic CMV inclusion disease?”

(6 components –

One big thing

Two small things

Two sensory issues

One lab thing)

1. IUGR

2. HSM (with jaundice & high LFTs)

3. Thrombocytopenia

4. Microcephaly

5. Sensorineural hearing deficit

6. Chorioretinitis

How common is congenital CMV infection in the USA?

1–2 % of births!

Can a fetus contract CMV from a maternal reactivation of the disease?

Yes, but very rare

What are the significant teratogenic effects of primary rubella infection?

(4 groups)

1. CV/heart problems (PDA & pulmonary artery stenosis)

2. Sensorineural hearing loss

3. Cataracts/glaucoma

4. IUGR

What percentage of rubella–exposed infants seems normal at birth?

>50 %

Rubella-exposed infants are at risk for late-developing problems in what four organ systems?

1. Special senses (hearing deficit)

2. CNS –

(MR, autism, etc.)

3. Endocrine (DM & thyroid dz)

4. Immune system (dyscrasias)

If a pregnant mother contracts CMV, what tends to happen to the fetus even if it does not become infected?

Low birth weight/SGA

CMV is very common in the USA. Its effect in pregnant is unusual, though, because maternal infection during what part of pregnancy most often causes fetal infection?

Equal –

It is always about 50 % (for primary infections)

What is the long-term complication rate for infants born with symptomatic CMV infection?

High! 40–90 %

What is the probability that an infant infected with CMV will be symptomatic?

10 % are symptomatic

What intestinal parasite is associated with bloody, mucous–y diarrhea and tenesmus?

Entamoeba histolytica

Eosinophilia is a clue to look for in what type of infection?

Parasitic

What is toxocara canis (in very general terms)?

A dog parasite (worm) that sometimes accidentally ends up in a person

(wrong host)

What types of problems/symptoms can toxocara canis cause?

• Pulmonary wheezing

• GI – hepatomegaly and/or abdominal pain

How can you remember that metronidazole treats Entamoeba histolytica?

Picture a “hysterical amoeba” riding the metro to destruction

(another option is tinidazole)

What other parasitic infection featuring bad diarrhea is treatable with metronidazole?

Giardia lamblia

What is the best way to treat scabies in children?

Permethrin cream

How do you identify scabies as the cause of a patient’s itching?

Look for long, narrow burrows at edges of clothing and intertriginous areas

How can you differentiate CMV from toxoplasmosis on head CT?

Both cause calcifications but CMV is periventricular (toxo is diffusely spread throughout)

How can you remember that metronidazole (Flagyl ^®) treats trichomonas?

They are “flagellated” organisms (sounds like Flagyl^®!)

If a patient is found to have trichomonas, how many people need to be treated?

The patient & all sexual contacts

Although current literature suggests that this medication is fine in some stages of pregnancy, for the boards, “can you use metronidazole in pregnancy?”

No

(Ob/gyns do use it, though, so don’t panic if you see this in real life)

What is the histological/micro buzzword that tells you that a patient has bacterial vaginosis?

“Clue cells”

(Cells that have little bits of stuff hanging from the edges of their membranes)

What kind of discharge is expected with bacterial vaginosis?

(aka “Gardnerella” –

because it is usually the dominant organism)

Thin & gray

(can be copious)

What do you expect to see on exam of a patient with trichomonas?

(2 “buzz phrases”)

1. Strawberry cervix

2. Yellow, frothy discharge

Mnemonic: The little whips make the discharge frothy, and cause petechiae on the cervix (the petechiae are the strawberry seeds)

What is the name of the organism causing “cat scratch fever?”

Bartonella henselae (a bacteria)

How is cat scratch fever usually treated?

Self-limited –

usually supportive care only

If a patient has unusually severe cat scratch fever, or is immunocompromised, how could you try to treat the infection?

(which medication?)

Azithromycin

How would you know that a patient’s cat scratch fever is unusually severe?(2 items)

Significant lymphadenopathy (large & painful)

&

Hepatosplenomegaly

What is the buzzword description for Haemophilus influenza on micro examination?

“Gram-negative pleiomorphic organisms”

Although H. flu is much less common in the USA due to immunization, which populations are likely to get it?

1. Immigrants/

foreign visitors

2. Unimmunized US children (younger than school aged)

What is the drug of choice for treating H. flu infection?

Ceftriaxone

How aggressive are H. flu infections in general?

Very aggressive (jump on them! With Ceftriaxone)

H . flu is one significant cause of otitis media. Do immunized children avoid this infection?

No – the vaccine does not prevent the OM infection

(It is non-typeable H. flu, not covered by the vaccine)

If a child has had a properly documented pertussis infection, do he/she still need to be immunized against it?

Yes!

[This is a change – natural immunity is now known to wane in as little as 4 years, so routine immunization is recommended EVEN AFTER a documented infection!]

Does antibiotic treatment help with the coughing of whooping cough?

It may decrease the coughing if started early, before coughing fits begin

Which antibiotics are most recommended for pertussis treatment?

Azithromycin or erythromycin

(macrolides)

What alternative antibiotic may be used for pertussis, in those older than 2 months?

Trimethoprim/sulfamethoxazole

In what phase of pertussis infection is it worthwhile to give antibiotics?

The catarrhal (URI) stage

How does erythromycin improve the catarrhal stage of pertussis infection?

It shortens it

(same for the other antibiotic treatment options)

In what other way is antibiotic treatment of pertussis infection helpful?

Decreases communicable period –

not communicable 5 days after antibiotics are started!

Elevated WBCs with a lymphocytosis, and a child with a prominent cough, is likely to be what disease?

Pertussis

(usually in an immigrant,

foreign visitor, or preschool group)

Bartonella henselae causes what disorder?

Cat scratch fever

What organism causes whooping cough?

Bordetella pertussis

Gram-negative pleiomorphic organisms  =  what bacteria?

H . flu

What organism is responsible for the H . flu type of otitis media?

Non–typeable H. flu

Thin, gray discharge  +  clue cells  =  what disorder?

Bacterial vaginosis

Frothy, yellow discharge  +  strawberry cervix  =  what disorder?

Trichomonas vaginalis

Contacts of individuals with pertussis need what treatment?

Erythromycin prophylaxis

Should individuals who have been successfully immunized against pertussis still receive prophylactic treatment?

Yes – it prevents spread of the organism (asymptomatic individuals may still spread it)

What two animals are the typical carriers for salmonella?

Chickens

&

Humans

(domesticated turtles can also occasionally be a source)

Vomiting, fever, and bloody loose stools 1–2 days after a group picnic is a likely vignette for what infection?

Salmonella

Should salmonella be routinely treated with antibiotics?

No –

It is likely to cause a carrier state

When might you treat salmonella enteritis with an antibiotic?

Very severe infection/immuno-compromise

To identify an infant at risk for congenital syphilis, should you test the mother, the infant, or either one?

The mother

(infant serum or cord blood is not sufficient)

If a mother is known to have had syphilis but it was treated prior to pregnancy with erythromycin, is congenital syphilis still a concern?

Yes –

Any non-penicillin treatment regimen is suspect

If an infant is born whose mother’s HIV status is unknown, what should you recommend?

HIV testing after counseling  +  consent of mother (some states allow testing without consent, but the above is preferred)

In which body systems does adenovirus cause infection?

1. Respiratory

2. GI

3. Conjunctivitis

/eyes

4. GU

How is the GI version of adenovirus transmitted?

Fecal-oral

How is the respiratory version of adenovirus transmitted?

Contact with infected secretions

What unusual version of adenovirus is sometimes seen in groups, after the individuals go swimming in a poorly chlorinated pool?

Pharyngoconjunctival fever

What worrisome, but usually spontaneously resolving, complication is sometimes seen with pharyngoconjunctival fever?

Corneal opacities

“Preauricular lymphadenopathy”  +  conjunctivitis (bilateral)  =

Adenovirus

Keratoconjunctivitis (also sometimes responsible for corneal opacities – self-resolving)

When is respiratory adenovirus most common?

Winter  +  spring

What treatment is needed for adenovirus infections?

Supportive care (+  isolation of health care workers & school children at home)

What are the symptoms of pharyngoconjunctival fever?

1. Fever (it’s in

the name

after all)

2. Conjunctivis

3. Pharyngitis,

rhinitis and

cervical

adenitis

Why does adenovirus sometimes present as meningitis?

It sometimes causes meningismus

What type of infection does adenovirus usually cause?

Respiratory

(10 % of peds respiratory disease is supposedly adenovirus)

What sort of GI symptoms does enteric adenovirus cause?

Watery diarrhea (most common in infants)

When adenovirus causes GU effects, what symptoms or signs are seen?

(3)

Gross hematuria

Dysuria

Frequency (more common in males)

Does adenovirus cause upper or lower respiratory symptoms?

Either

If you want to identify adenovirus as the cause of a child’s infection, what body fluids should you send?

Stool and nasopharyngeal swab have the highest yield

(can also attempt to isolate from urine or conjunctival swab)

When adenovirus causes lower respiratory infection, what part of the lungs is most likely to be affected?

The lower lobes

During adenovirus infection, what is a CBC likely to show?

Left shift

+

leukocytosis or leukopenia

Which bacterium causes diphtheria?

Corynebacterium diphtheriae

What is the main buzzword for diphtheria infection?

Gray *pseudomembrane* (in the throat)

What aspect of diphtheria infection causes its associated problems?

The exotoxin it makes

What creates the pseudomembrane in diphtheria infection?

Tissue edema

+

Coagulative necrosis of the mucous membrane

How is diphtheria spread, generally?

Respiratory droplets (+ sometimes via breaks in skin, conjunctiva, etc.)

During which season do most diphtheria cases occur?

Winter (possibly due to more indoor crowding)

If children or adults are exposed to an active case of diphtheria, but have previously been fully immunized, should anything be done?

Yes –

They require erythromycin or PCN & a booster if the last immunization was >5 years ago

Is diphtheria still endemic in some parts of the world?

Yes –

In most of the developing world

What are the four common forms of diphtheria?

1. Nasal (infants, especially)

2. Pharyngotonsillar

3. Laryngeal

4. Cutaneous

Why is cutaneous diphtheria important?

It is a big reservoir for infection in warm climates

How long is the incubation period for diphtheria?

1–6 days

Which type of diphtheria is most dangerous?

Laryngeal

(due to easy compromise of the airway)

Which form of diphtheria is most likely to produce a carrier state?

Nasal

What are the four main factors that determine how severe a particular case of diphtheria is likely to be?

1. Prior immunization (less severe)

2. Virulence (toxigenic form is worse)

3. Time to antitoxin (less is better)

4. Location of membrane (laryngeal)

What are the four main complications of diphtheria?

1. Airway obstruction/compromise

2. Myocarditis

3. Renal tubular necrosis

4. Demyelination of motor nerves

What precautions should you take with hospitalized diphtheria patients?

Respiratory isolation until 3 consecutive cultures from infection sites are negative

What is the mainstay of treatment for diphtheria infection?

Diphtheria antitoxin

What is the only form of diphtheria that can be treated by antibiotics alone (no antitoxin needed)?

Cutaneous

How does laryngeal diphtheria present?

Like croup

(it often develops from the tonsillo-pharyngeal form)

After the symptoms of diphtheria begin, how long is it until pseudomembranes start to form?

1–2 days

Although cardiovascular collapse can occur with diphtheria toxin production, the usual course for diphtheria-induced myocarditis is . . . ?

Spontaneous resolution

What, in general, do the neurological complications of diphtheria consist of?

Demyelination of motor pathways

(mainly oculobulbar,

but can also affect peripheral nerves)

What two factors determine the likelihood of diphtheria complications?

1. interval between symptom onset and antitoxin administration

2. quantity of membranes

How does nasal diphtheria present?

Like a nasal foreign body except bilateral

(initially clear discharge,

then serosanguinous, then smelly mucopurulent)

What happens if you try to remove the pseudomembrane of diphtheria?

It bleeds

(most exudates, etc., do not)

What special finding in the vital signs suggests diphtheria?

Heart rate unexpectedly high for temperature

What unusual effects can diphtheria have on the special senses?

Conjunctivitis

&

Aural diphtheria (otitis externa)

Although diphtheria is a clinical diagnosis, what confirmatory test should be sent?

A culture from the membrane or just below the membrane

How many doses of diphtheria vaccine are needed to immunize a healthy young child?

Five

(roughly:

2 months

4 & 6 months

18 months

4 years)

How is diphtheria immunization different for patients older than 7 years?

(2 ways)

1. Different vaccine –

Td or Tdap (adult type) is given rather than DTaP or DT

2. Different schedule –

Two doses at least 4 weeks apart, then repeat 6 months later

What does the lower-case “d” vs. the capital “D” indicate, in the vaccine name?

The lower-case “d” indicates a reduced dosage diphtheria used in older patients

How is diphtheria treated?

1. An IV bolus of antitoxin (amount varies)

2. 14 days of PCN–G, procaine,

or E–mycin

How do people become infected with ascaris?

Fecal-oral ingestion of eggs

What are the main organ systems affected by ascaris?

Pulmonary & GI

The life cycle of ascaris is 2 months long. Where do the worms travel in the body?

(4 phases)

1. Eggs to gut then to portal venous system

2. Pulmonary vessels into alveoli

3. Coughed up & swallowed

4. Grow to adults in small intestine

What types of animals can ascaris lumbricoides infect?

Humans only

(1/4 of the world’s population is infected!)

What problems can ascaris cause in children with abdominal ascaris?

(5 possibilities)

1. Obstruction

2. Malabsorption

3. Growth failure

4. Intussusception

5. Abdominal pain

Where does obstruction due to ascaris occur?

Ileocecal valve

What sorts of pulmonary symptoms/signs are seen as ascaris migrates through the lung?

Fever, cough, dyspnea, & wheezing

(causes an eosinophilic bronchopneumonia)

Will you see infiltrates on CXR during the pulmonary migration of ascaris?

Yes

Are patients with ascaris usually symptomatic?

No –

If the infection is only moderate, most are asymptomatic

If a patient is diagnosed with ascaris, what other things should you look for?

Other parasites (often multiple infections)

How is ascaris treated?

A single dose of pyrantel pamoate

(alternate regimen for kids older than 2 years: mebendazole for 3 days)

Where does aspergillus usually cause infection?

The lung

Is aspergillus likely to cause infection in HIV+/AIDS patients?

No

(infection fighting depends on phagocytes, not T-cell immunity, for this bug)

What is the most common form of aspergillus infection? Is it invasive?

• Aspergilloma (pulmonary fungus ball)

• No

Which patients are at risk for invasive aspergillosis?

Those with neutrophil or macrophage problems

(Including chemo, leukemia, long-term Abx, or steroid use)

Where is aspergillus found,

& how is it transmitted?

• Everywhere

• Transmitted by lightweight airborne spores

In what ways does aspergillosis affect healthy people? (2)

Ear & sinus infections in warm, wet regions

&

Allergic bronchopulmonary aspergillosis

What is allergic bronchopulmonary aspergillosis?

Local pulmonary reaction to aspergillus spores trapped in mucus

Which patients are at risk for allergic bronchopulmonary aspergillosis?

Those with chronic respiratory disorders

What are the symptoms of allergic bronchopulmonary aspergillosis?

(2 physical findings)

(1 lab finding)

(1 radiological finding)

(1 icky finding!)

Wheezing

Fever

Eosinophilia

Infiltrates on CXR productive cough

(+  brown mucous plugs)

As with most invasive fungal diseases of the immunocompromised, what is the prognosis for disseminated aspergillosis?

Bad –

Amphotericin B

&

Debridement are urgently needed

If an aspergilloma causes symptoms, what symptom is it most likely to cause?

Hemoptysis

Why are the infiltrates seen with allergic aspergillosis “transient?”

Because they develop in areas where mucous plugs cause obstruction (if the plug is coughed up, they disappear)

How does “otomycosis” appear on physical exam?

Black spores begin at the TM, & may fill the EAM!

(yuck!)

How does sinusitis from aspergillus present?

Chronic sinusitis that doesn’t respond to Abx

What are the two buzzwords for allergic pulmonary aspergillosis?

Transient infiltrates

&

Brown or dark mucous plugs

What lab findings suggest aspergillosis?

1. Elevated Ig E

2. Eosinophilia

3. Branching, septate hyphae

Can the aspergillus species that causes human infection be cultured?

Yes

How is noninvasive aspergillus sinusitis treated?

Surgical drainage/

debridement

Aspergillus otomycosis usually coexists with chronic bacterial otitis. How is it treated?

Debridement & treat the external infection (bacterial)

How do people encounter atypical mycobacteria?

Air, water, meat, & egg products

What are typical mycobacterial infections?

(3)

1. M. tuberculosis

2. M. bovis

3. M. leprae

What are atypical mycobacterial infections?

Any that are not the three typical infections

(Those three are tuberculosis, bovis, & leprae)

What type of infection commonly develops with atypical mycobacterial infection in immuno competent individuals?

Cervical adenitis in preschoolers

(rarely, may also cause otitis or mastoiditis)

What immunocompromised patients are at risk for

atypical mycobacterial infection?

HIV

(other T-cell disorders do not increase rates of atypical mycobacterial infection)

In what situation might atypical mycobacteria cause a chronic infection of skin, soft tissue, or bone?

Following trauma or surgery

What signs suggest that cervical adenitis is due to atypical mycobacteria?

(3 signs)

1. Single node or single region of LAD

2. No systemic symptoms

3. Not warm or tender

Why is the cervical adenitis of atypical mycobacteria often called a “cold abscess?”

It is literally not warm, as most abscesses would be

How is the diagnosis of atypical mycobacterial infection confirmed?

Culture or micro identification from specimen

What prophylactic medications may be given to HIV+ children to prevent atypical mycobacterial infection?

Azithromycin weekly

How is isolated cervical adenitis due to atypical mycobacterium treated?

Surgical excision (usually no meds needed)

Why is draining cervical adenitis due to atypical mycobacterium a bad idea?

It can produce a chronically draining situation

(unless you excise it after making the diagnosis)

After excising an atypical mycobacterium cervical adenitis, should you follow up with an antibiotic?

No – but the child should be followed for recurrence for 1 year

What additional diagnostic should be obtained for patients with atypical mycobacterium infection?

CXR

Fever, malaise, and hemolytic anemia go with what tick-borne illness?

Babesiosis (although most people are actually asymptomatic)

Can babesiosis be transmitted from mother to child in utero?

Yes – but uncommon

The ticks that carry babesiosis are also frequently carrying what other disease?

Lyme

Where in the body does babesiosis live?

Inside the RBC

What patients are at special risk of more severe disease with babesiosis?

(4)

1. Extremes of age

2. Immunocompromised

3. No spleen

4. Coinfected with Lyme disease

What very similar syndrome to babesiosis is seen in the Western USA?

WA1 protozoal infection

(W – Western, A – American)

Approximately what percentage of babesiosis patients also has Lyme infection?

¼

What is the typical presentation for a patient with symptomatic babesiosis infection?

Systemic symptoms:

1. Intermittent fevers – may be high (40 °C)

2. +/− chills, myalgias, arthralgias

Do babesiosis patients have hepatosplenomegaly?

Sometimes – not reliable

(but the spleen is very important in fighting this infection)

What blood test should you send if you are hoping to identify babesiosis infection?

Thick & thin smear (same as malaria)

What special microscopic appearance is the “buzzword” for babesiosis on the smear?

“Maltese crosses” –

due to the characteristic grouping of 4 parasites together

What might the UA of a babesiosis patient show?

(2)

Proteinuria

&

Hemoglobinuria

In addition to anemia, what other CBC abnormalities often occur in babesiosis?

(2)

Thrombocytopenia

&

Lymphocytosis (often atypical)

How are mild or asymptomatic cases of babesiosis treated?

Usually no treatment needed

What stains will usually identify protozoal parasites like babesiosis?

(2)

Giemsa or Wright’s

What type of anemia is seen with babesiosis?

Normocytic, normochromic

(Remember, it is an acute, not chronic, problem – no time to change the size of the cells being synthesized)

For patients with significant symptoms of babesiosis, or significant risk factors (asplenic or immunodeficient), how should babesiosis be treated?

7 days of clindamycin or quinine

In rare cases of life-threatening babesiosis, how can the patient be treated?

Exchange transfusion

What are the two most worrisome complications of babesiosis?

1. Hemophagocytic syndrome (progressive pancytopenia & LAD)

2. ARDS-type pulmonary problems (usually occur after treatment has begun)

Can you catch babesiosis more than once?

Yes

How long does a tick need to be attached to transmit babesiosis (or Lyme disease)?

Usually 24 h

(some medical texts dispute this)

How does someone get blastomycosis?

Inhalation of spores (from soil)

Is blastomycosis more common in children or adults?

Adults

What are the three forms of blastomycosis infection?

1. Pulmonary

2. Cutaneous

3. Disseminated

What form of blastomycosis is most common in children?

Pulmonary

Although many cases of blastomycosis are asymptomatic or spontaneously resolving, how is it treated when intervention is needed?

Mild-moderate –

Itraconazole or fluconazole

Severe – amphotericin B

(treatment requires at least 6 months)

How is cutaneous blastomycosis acquired?

Usually from the pulmonary tree – sometimes directly through skin inoculation

What types of skin lesions might you see with cutaneous blastomycosis?

Nodules, abscesses, ulcerations

Where in the USA are you most likely to develop blastomycosis?

Central & Southeastern USA

(Blastomyces is present in a variety of other countries, also)

Which neonates are at greatest risk for developing a brain abscess after meningitis?

Those who had gram–negative meningitis

In general, what two organisms are most commonly found in brain abscesses?

(all ages)

Staph

&

Strep

(various species)

Abscesses in the frontal lobes of the brain usually develop from what source?

Frontal sinusitis

About what percentage of children with congenital cyanotic heart disease will develop a brain abscess?

About 3 % (!)

After having a brain abscess, what proportion of kids will have some long–term neurological problems?

About 1/3

What procedure must not be performed on patients with brain abscesses?

LPs

(it is a space-occupying lesion and there is a risk of hemiation)

For patients who can talk, what is the most common complaint associated with a brain abscess?

Headache

Headache  +/−  fever  +  a focal neurological complaint  =

Brain abscess

Do patients with brain abscesses develop meningismus?

Yes –

About 1/3 will

If CSF were obtained from a brain abscess patient, what would you expect to find?

↑ protein

↓ glucose  +  pleocytosis

(no organisms unless the abscess has ruptured)

How are brain abscesses typically treated?

Antibiotics (at least 3 weeks)

+

Surgical excision (if it’s a single abscess in an accessible location)

If a patient develops a brain abscess and has no obvious source, what three services need to evaluate the patient for predisposing factors?

1. Dental

2. ENT

3. Cardiology

Breast abscesses in adolescents are likely due to what organisms (in general terms)?

Staph aureus

&

Sexually transmitted diseases (STDs)

How are breast abscesses in adolescents treated?

(3)

1. IV oxacillin or nafcillin, then PO meds (total treatment time of 14 days)

2. I & D

3. Compresses

(all are needed)

Should a breast-feeding adolescent or adult continue breast-feeding if she develops a breast abscess?

Yes, from the unaffected breast

(milk should still be expressed, but discarded, from the affected side)

What is the most common cause of bronchiolitis?

RSV (respiratory syncytial virus)

How is RSV bronchiolitis generally treated?

Supportive care

+

β-adrenergic agent for wheeze

Are bronchodilators, or anti-inflammatories such as steroids, useful in treatment of RSV?

Bronchodilators are often used in hospitalized patients, although it is not clear from data whether it is helpful or not

Steroid use is not supported by available data

Which medication is indicated for treatment of severe RSV cases, although its efficacy is not entirely clear?

Ribavirin –

Severe disease and/or high risk for severe disease (e.g., transplant patients)

Most effective if started early!

What medication may be given as prophylaxis against RSV infection, and what kind of treatment is it?

Palivizumab

(Synagis^®)

It is a monoclonal antibody

(administered IM once per month during RSV season)

What is usually considered to be “RSV season” in the USA?

November through end of March

Which chronic lung disease patients should receive RSV prophylaxis?

≤2 years old

&

requiring treatment for the lung problem within 6 months of the beginning of RSV season

Which heart patients should receive RSV prophylaxis?

≤2 years old

&

cyanotic or complicated congenital heart disease

Which three sets of preemies require palivizumab prophylaxis?

• Born ≤ 28 weeks & ≤12 months old at RSV season start

• Born 29–32 weeks & ≤ 6 months old at RSV season start

• Born 32–35 weeks & ≤ 3 months old at RSV season start

Which children require RSV prophylaxis at any age?

Those with difficulty handling airway secretions

Where might patients encounter brucellosis?

(2)

1. Contact with farm animals

2. Unpasteurized dairy products

Why is brucellosis sometimes difficult to culture?

It reproduces inside the host’s phagocytes

How long does brucellosis infection usually last?

Less than 3 months

How is brucellosis treated?

TMP/SMX or doxycycline – adding rifampin may decrease relapse rates

Why is it important to complete the antibiotic regimen for brucellosis?

To prevent relapses

For symptomatic patients, what are typical findings of brucellosis?

Hepatosplenomegaly

+

Lymphadenopathy

(localized infections may be found anywhere, however, including the vertebra)

What type of bacterium is brucellosis?

Gram negative (there are four types of brucellosis)

Brucellosis is well known for its tendency to affect which organ system?

Nearly any of them –

Endocarditis, gut complaints, neuropsychiatric effects, joint problems, etc.

Where does campylobacter infection come from?

Domestic & farm animals (meat, unpasteurized milk, contaminated water)

+

Person to person (fecal-oral)

What are the three forms of campylobacter infection?

1. Systemic

2. Enteritis (ileocolitis)

3. Antral gastritis

What is the most common type of campylobacter infection seen in children?

Inflammatory ileocolitis

What special “after effects” of campylobacter are sometimes seen?

Postinfectious autoimmune complications

What postinfectious complications are most common following campylobacter infection?

1. Guillain–Barre

2. Reiter syndrome

3. Reactive arthritis

4. Erythema nodosum

When is campylobacter infection most common?

Summertime

(unlike most bugs that like the winter)

Nausea, vomiting, halitosis, and crampy epigastric pain suggest what infectious diagnosis?

Campylobacter gastritis

Along with Yersinia enterocolitica, what is campylobacter known for mimicking?

Appendicitis!

(& sometimes intussusception)

Most patients with campylobacter recover quickly. Which two long-term complications are sometimes seen with campylobacter?

Arthritis

&

Guillain-Barre

Campylobacter is estimated to be responsible for what percentage of the US Guillain-Barre cases?

40 %

Does campylobacter enteritis require treatment?

No –

It usually resolves in about 5 days

What is a typical presentation of campylobacter enteritis?”

Fever, abdominal pain, bloody or mucous-y diarrhea

Are the animals infected with the various types of campylobacter ill?

No – they are asymptomatic

Should campylobacter gastritis be treated?

Yes – if not treated it tends to continue in a chronic phase for months

How can campylobacter be rapidly identified in fresh stool specimens?

The curved rods “dart around”

What is the gold standard for identification of campylobacter pylori (the gastritis bug)?

Gastric mucosa biopsy & culture (from the biopsy)

What medication is used to treat campylobacter infections caught early?

Azithromycin (many others are often also effective)

How do most patients acquire campylobacter infection?

Contact with contaminated meat

(proper cooking does kill it)

Does campylobacter infection pose any risk to fetuses?

Yes

1. Infected mothers (even if asymptomatic) have more abortions & preterm deliveries

2. Fetal & newborn fatal infection sometimes occurs

Do you need to get rid of your cat if someone in the family develops cat scratch disease?

No – the cat is not likely to carry the bacteria chronically

What is the general appearance of a lymph node infected with Bartonella henselae?

1. Central necrotic area

2. Hypertrophied

3. Thickened cortex

4. Pus-filled sinuses

Which cats are most likely to transmit cat scratch disease?

Those less than 1 year old

The most frightening complication of cat scratch disease is encephalitis. What is the typical course of this complication?

• Develops about 1 month after basic cat scratch disease

• Sudden onset

• Coma

• Full recovery

Does cat scratch disease cause a rash?

No –

But there may be a papule that changes to a crust at the site of the cat contact

Where will you see lymphadenopathy following cat scratch disease exposure?

The lymph nodes draining that area (unilateral)

What percentage of the enlarged lymph nodes of cat scratch disease will form a tract thru the skin?

<50 %

How should you treat a tender, large, cat scratch disease node?

Drain it

In cases of severe cat scratch disease or immunocompromise, how should it be treated?

Azithromycin or Bactrim^® first choice –

IV or IM gentamicin also used

How long will it take for all symptoms of cat scratch disease to disappear?

Weeks to months (nodes resolve last)

Unilateral proptosis, lid swelling, and fever could be signs of what dangerous syndrome?

Cavernous sinus syndrome (infectious etiology)

What infections put patients at special risk for developing cavernous sinus syndrome?

Any facial infection (including dental, sinus, & significant acne)

How great is the mortality from infectious cavernous sinus syndrome?

About 25 %

How useful are blood cultures for treatment of infectious cavernous sinus syndrome?

Actually quite useful –

70 % will grow something

How long should you treat infectious cavernous sinus syndrome?

Approximately 4 weeks after symptoms resolve

What unfortunate surprise often occurs with infectious cavernous sinus syndrome?

Relapse (locally) or development of embolic abscesses about 4 weeks after treatment is completed

What is the usual long-term outcome for patients who recover from infectious cavernous sinus syndrome?

Long-term cranial nerve defects

If infectious cavernous sinus syndrome is not rapidly treated, how will it present?

Meningitis/overwhelming sepsis

What is the main physical finding to look for with a case of cellulitis (suggests you might want to admit the person)?

Lymphangitis

(aka lymphangitic spread)

Facial cellulitis due to what organism often leads to pneumonia, arthritis/osteomyelitis, and other disseminated foci of infection?

Haemophilus influenza type B

Patients suspected of having cavernous sinus syndrome should have what radiological study?

MRI with & without gadolinium

(CT is okay but not the gold standard)

Cervical motion tenderness on gyn exam indicates what general problem?

Peritonitis

(may or may not be gyn related)

What do we use KOH preps to identify, in a gyn patient?

Yeast (Candida) infection

What is the trouble with treating vaginal yeast infections with the one–time dose of fluconazole?

(2)

1. Costs the same as other regimens

2. No symptom relief for at least 1–2 days

For any patient found to have cervicitis, what two infections must you presumptively treat?

Chlamydia & gonorrhea

What is the most cost–effective treatment regimen for gonorrheal/chlamydial cervicitis?

Ceftriaxone 250 mg IM or Cefixime 400 mg PO

+

Doxycycline,

100 mg PO BID × 7 days

What is the problem with treating adolescents with the doxycycline STD regimen?

(4)

1. Poor compliance due to BID dosing

2. 7 days of treatment

3. Need to fill prescription

4. High stakes for future fertility

What treatment regimen for gonorrhea/chlamydial cervicitis can you give during your patient’s visit to ensure compliance?

Ceftriaxone

250 mg IM × 1

+

Azithromycin 1 g PO × 1

(can also give single PO dose of 2 g azithromycin alone, but nasty lower GI side effects usually follow)

Gram–negative diplococci seen with cervicitis  =  what infection?

Gonorrhea

What exam must be performed in females presenting with cervicitis or vaginal yeast infections?

A bimanual pelvic exam

Should a patient with cervicitis have any pain, or other abnormal findings, on gyn exam?

No –

Anything else suggests PID, ectopic pregnancy, etc.

How is the ulcer of chancroid different from the initial syphilitic ulcer (which is also called a chancre)?

The syphilis ulcer is painless

How are the ulcers of chancroid different from those seen in HSV?

Chancroid ulcers are deep with undermined edges

(HSV ulcers are very shallow, not undermined, & multiple)

Like HSV, chancroid requires what condition to infect a person?

A break in the skin (including an abrasion)

What microbe causes chancroid?

Haemophilus ducreyi

(Gram negative)

Under what circumstances is chancroid transmitted?

Sexual contact with someone with an ulcer

What three other STDs should be considered in individuals who have developed chancroid?

10 % coinfection with HSV, syphilis, or HIV

(all also transmitted via breaks in skin)

How is chancroid treated?

Azithromycin

1 g PO × 1

Or

Ceftriaxone

250 mg IM × 1

(Cipro 3 days & E-mycin 7 days are also options)

Regional lymphadenopathy usually accompanies chancroid. What complication can this lead to?

Fluctuant or draining bubo

(A bubo is an inflamed lymph node)

How is chancroid diagnosed?

Clinically

(a follow-up culture to confirm is the gold standard)

What three chlamydial bacteria affect humans?

1. C . trachomatis

2. C . pneumoniae

3. C . psittaci

Which type of chlamydia is usually responsible for chlamydial pneumonia in infants?

Chlamydia trachomatis

Which type of chlamydia is responsible for conjunctival infection & blindness in the developing world?

C . trachomatis

Which type of chlamydia is the common STD?

C . trachomatis

Which chlamydial type is usually responsible for chlamydial pneumonia in adults & older children?

C . pneumoniae

Chlamydial pneumonia causes approximately what proportion of childhood community-acquired pneumonias (CAP)?

20–25 %

How do most patients with chlamydial pneumonia present?

Asymptomatic – they don’t present

How do infants generally acquire chlamydial pneumonia?

Via vaginal delivery (although C/S does not fully prevent it)

How is Chlamydia psittaci acquired?

Inhaled bird excrement or bird secretions

(The bird may be healthy or sick)

In addition to chlamydial pneumonia, what other problems can Chlamydia psittaci sometimes cause?

Bronchitis, pharyngitis, & otitis media

(nasal discharge is common with all 3)

What is the buzzword for chlamydial infection on microscopic evaluation?

Inclusion bodies

(It’s an obligatory intracellular bacteria)

How is Chlamydia pneumoniae acquired?

Inhaled aerosolized droplets

Do infants with C . trachomatis have a fever?

No

Do children with C . pneumoniae have a fever?

Generally yes

In general, how are chlamydial infections treated?

Macrolides

What is the overall probability of resistance to erythromycin in chlamydial infection?

20 %

In a case of known maternal GU chlamydial infection, is treatment with topical erythromycin to the conjunctivae sufficient?

No – it will not

eliminate nasopharyngeal colonization

If you suspect chlamydial infection, but the immunofluorescent study for Chlamydia is negative, what does this mean?

Nothing

(>50 % of chlamydial infections have negative results)

If a mother with untreated GU chlamydial infection delivers a baby, how should you treat the (asymptomatic) infant?

You don’t – monitor for signs of infection

If a mother delivers a baby who develops a chlamydial infection, what is the appropriate treatment?

Oral erythromycin × 14 days

(don’t forget that mom and partner(s) need treatment as well)

After completion of an antibiotic course for neonatal chlamydia infection, what should be done?

Follow–up –

Erythromycin is only 80 % effective in eradicating chlamydial infections, so a second course could be needed

What are the typical CXR findings of chlamydial pneumonia (infants)?

• Bilateral infiltrates

• Hyperinflation

If an infant is found to have chlamydial infection, what else must you do, in addition to treating the chlamydia?

Look for other STDs

(syphilis, Hep B, HIV, gonorrhea, etc.)

Although humoral immunity is important in preventing and fighting varicella virus (antibodies), what immune component is most critical to preventing severe disease?

Cell-mediated immunity

(T-cell system)

What organ systems may be affected by varicella zoster, if it disseminates?

Basically, any (pneumonitis is especially common)

What is the main effect of congenital varicella infection?

Limb scarring and atrophy

(CNS & eyes may also be affected)

Can a person with herpes zoster (shingles) spread the virus?

Yes –

Through contact with affected skin; respiratory transmission is a remote possibility

The severe complications that cause death from varicella infection are more common in adults than children. How much more common?

35 times!

How likely are you to catch varicella if you are exposed and are not immune?

98 % (!)

(figures vary)

If an individual has had chicken pox, is he or she immune for life?

Generally yes

(reinfection is possible, but it is usually mild)

What patient groups are at highest risk for varicella complications?

(6)

(two age groups)

(one medication)

(four conditions)

1. Infants 3 months – 1 year

2. Adolescents/adults

3. Chronic aspirin therapy

4. Immunocompromised

5. Pulmonary disease (incl. asthma)

6. Pregnant women

7. Chronic skin disorders (severe eczema, etc.)

In what order does the varicella rash develop?

(4)

1. Macule

2. Papule

3. Vesicle

4. Crust

In addition to the typical rash stages, what other buzzwords describe the varicella rash?

(2)

1. Rash in various stages over body

2.“Dewdrop on a rose petal” appearance

What are the typical seasons for varicella?

Winter & spring

Is it alright to use aspirin or NSAIDs for children with chicken pox?

No –

Aspirin  +  varicella  =  Reye’s syndrome

NSAIDS  +  varicella  =  increased incidence of bacterial superinfection

When should antiviral therapy be given to chicken pox patients?

(1 situation)

(2 age groups)

(4 medical conditions)

1. Hospitalized patients

2. Newborns & adolescents

3. Immunocompromised (incl. those on inhaled steroids)

4. Chronic skin or lung disease

5. Pregnant

What type of isolation is needed for hospitalized varicella patients?

Contact and respiratory (while vesicles present)

How long should an exposed, varicella susceptible individual be isolated?

(if hospitalized)

From days 8–21 after rash develops in the index case

Who usually has more severe disease, the index case, or the secondary cases, in varicella infections?

Secondary cases, in general

In current practice, which patient groups should not receive varicella vaccine?

(3)

1. Infants <1 year

2. Immunocompromised (but some HIV+ should get it)

3. Pregnant women

4. Patients with malignancies of the blood/bone marrow or lymphatic system

5. Recently received blood products (up to 11 months prior)

What is required for maximum protection from the varicella vaccine?

A second dose

(the regimen is now two doses, to minimize declining immunity after vaccination)

If a varicella non-immune patient is exposed to varicella, but cannot receive the vaccine, what other prevention strategy should be considered?

VZ-IG

During what portion of pregnancy can varicella cause birth defects?

Between the 8th and 20th weeks

Teratogenic varicella affects what portion(s) of the developing embryo/fetus?

The ectoderm

(eyes, skin, CNS, & limbs are affected)

Why are the limbs affected in teratogenic varicella?

Damage to the ectodermal structures of the brachial & lumbar nerve plexi causes limb abnormalities

How should you care for a pregnant mother exposed to varicella in the first or the second trimester?

VZ-IG if not immune –

Acyclovir if chicken pox has already developed

If the embryo or the fetus is infected by varicella in the 1st or the 2nd trimesters, what is the likely outcome?

Bad –

death or severe CNS damage

Although varicella can have teratogenic effects, congenital varicella means something else. What does it mean?

Maternal infection developed in the last 3 weeks of gestation, or first week after birth

If the infant develops congenital varicella infection, when will his/her illness become clinically apparent?

First 10 days of life

If the mother develops varicella in the last 3 weeks of pregnancy, how likely is the fetus to develop varicella?

Quite likely –

¼ to ½ will contract the disease

What determines the severity of congenital varicella infection (mainly)?

When the mother is infected – ≤5 days before delivery is bad

(no time for maternal antibody to be made & transferred)

What is the pattern of the rash seen in congenital varicella infection?

Centripetal but sparing extremities

(centripetal = going toward the center of the body)

If the newborn does not have maternal antibodies to varicella, peripartum infection can be quite severe. How does varicella typically cause death?

Due to pulmonary involvement

If a mother develops varicella >5 days prior to delivery, should her infant receive immunoglobulin?

No – the infant is assumed to have already received maternal immunoglobulin

If VZ–IG is given empirically to a neonate, how long must the infant be kept in respiratory isolation?

28 days

(immunoglobulin extends the incubation period)

What is the other name for perleche?

Angular cheilosis

What organism is generally responsible for perleche?

Candida

(plus licking corners of mouth, braces, or bad overbite)

In an older child or adult, consider staph aureus infection, iron or riboflavin deficiency

Are infants with thrush consistently symptomatic?

No – some are asymptomatic

A weepy and erythematous rash in skin folds, confluent, with a scaling edge suggests what problem?

Intertriginous candidiasis

How is intertriginous candidiasis treated?

Keep area dry

+

Nystatin cream

(or other topical antifungal)

How is disseminated candidiasis treated?

IV amphotericin B × 6 weeks

OR

Fluconazole (static) & the newer “fungin” drugs (fungicidal)

(Example: micafungin)

In settings of either immunocompromise or imbalance of bacteria, oral thrush often progresses to what difficult-to-manage problem?

Esophagitis

Candidal infections regularly cause what secondary problem?

(a general, body-wide problem)

Allergic reactions (rash, itch, asthma, exacerbations, a type of colitis, etc.)

Scattered erythematous papules in the diaper area, or a confluent rash with a scalloped or a scaling border  =  ?

Diaper dermatitis (candida)

Is nystatin used to treat vaginal candidiasis?

No –

use one of the “azoles”

Which famous fungus comes from the dry soil in the southwestern USA?

Coccidioides

How long is the incubation period for coccidioides?

Up to 30 days

What is the common name for the illness it causes?

San Joaquin Valley fever or Desert Rheumatism (because it often causes joint pain & myalgias)

What is the usual course for a coccidioidomycosis infection?

Asymptomatic pulmonary infections (60 %)

Which ethnic groups are especially likely to have bad episodes of coccidiodomycosis?

Hispanic

African American &

Filipino

Mnemonic: Think of half (HAAF) an infected coccyx, having trouble breathing on a trip to the desert to remember this disease, and the ethnic groups it especially affects!

Adults with symptomatic pulmonary coccidioidomycosis complain of hemoptysis. How do children present?

1. Fever, cough, pleuritic chest pain

2. Arthralgia and myalgia

3. Night sweats

4. Maculopapular lower body rash

What finding on micro exam (from any source) suggests coccidioidomycosis?

Large “spherules”

A skin test (delayed-type hypersensitivity) is available to aid in the diagnosis of coccidioidomycosis. In what situation is the test often falsely negative?

Disseminated disease

(due to anergy)

How is disseminated coccidioidomycosis treated?

Ampho B, generally

If it is able to disseminate, where does coccidioides like to go?

Bones & joints

Lymph nodes

CNS

Abdominal sites

What causes Condyloma acuminata?

HPV –

human papillomavirus

(aka papova viridae)

What is the histologic buzzword for condyloma?

“Koilocytosis”

(& atypical nuclei)

koilocytosis means an empty space near the nucleus

How long can the incubation period for HPV last?

Several years

How common is HPV infection?

Very common

(it is the most common STD –

at least 20 % of sexually active women are infected)

What easily accessed substance makes it much easier to visualize areas infected with HPV?

Acetic acid

(leave on for 5 min – affected areas turn white)

What is the usual course of HPV infection?

Like herpes, the immune system eventually keeps the virus from manifesting & may eliminate it

Does genital Condyloma acuminata in a child indicate sexual abuse?

Sometimes –

It should always be investigated but close nonsexual contact can also transmit the virus

A vaccine for HPV infection is now available. What is the main restriction on who can get the vaccine?

It is given to patients between the ages of 9 and 26 years old (target age for vaccination is 11–12 years old)

Is HPV vaccination useful for boys, as well as girls?

Yes –

The quadrivalent vaccine prevents infection with strains linked to genital cancers in males

What is the other name for neonatal conjunctivitis?

Ophthalmia neonatorum

Does GC conjunctivitis lead to blindness?

Yes, without prompt therapy

Why must conjunctivitis never be treated with steroid drops by a primary care doctor?

Could accelerate an undiagnosed herpes keratitis

What is the buzzword for herpes keratitis on physical exam?

“Dendritic” (branching) pattern of fluorescein uptake

What is the other name for croup?

Laryngotracheobronchitis

What causes croup?

A variety of viruses

(the symptom constellation defines the disorder rather than the causative agent)

What three symptoms characterize “croup?”

1. “Barky” cough

2. Inspiratory stridor

3. Hoarseness

How is “spasmodic croup” different from regular croup?

1. It occurs only at night

2. Child appears well (or minimally ill)

During what season is croup most often seen?

Winter

What is the typical age & gender for a croup patient?

<3 years (usually 2) and male

What is the buzzword for croup on X–ray, and why does it occur?

• “Steeple sign”

• Subglottic narrowing due to inflammation near the cricoid

What diagnostics are useful for croup patients?

(2)

Pulse ox

(r/o hypoxia)

&

AP & lateral neck X–ray

In addition to “steeple sign”, what else should you be looking for on X-ray if you suspect croup?

(3)

1. Foreign body

2. The “thumb” of epiglottitis

3. Retropharyngeal infection or abscess

For croup patients requiring medical intervention, what therapies are useful?

(2)

1. Racemic epi (nebulized)

2. Steroids

(usually a single dose of dexamethasone – 45 h T_1/2)

What simple interventions have long been thought to improve symptoms in croup patients, although recent data does not support this?

(2)

Humidified air

&

Cold air

How long must you observe a patient who requires racemic epi treatment for croup, before discharging to home?

At least 4 h after treatment

(some patients rebound & worsen after treatment)

Recurrent croup suggests that a child may be suffering from one of the two underlying disorders. What are they?

1. Subglottic stenosis/congenital anomaly

2. GE reflux

Cryptococcus usually affects what organ system?

CNS

(occasionally lungs & other areas)

How is cryptococcal meningitis treated?

Amphotericin B

+

Flucytosine

(6 weeks)

Recurrence of cryptococcal meningitis is common. How do we prevent this in the immunocompromised?

Maintenance fluconazole

What is the prognosis for cryptococcal meningitis (properly treated)?

Very good

(Fatal without treatment, by the way)

What special CSF tests should be done if cryptococcal meningitis is suspected?

(2)

India ink stain

&

Cryptococcal antigen

Where is Cryptococcus neoformans found in nature?

Pigeon droppings & soil

Are immunocompromised hosts at risk for cryptococcal recurrences?

Yes

(at least 1 year of regular follow-up is required)

What are the two common presentations of pulmonary cryptococcosis?

Asymptomatic

&

Cough & hemoptysis

What are the symptoms of cutaneous larva migrans?

Itching & serpiginous erythematous lines

(serpiginous  =  snakelike)

What usually causes cutaneous larva migrans?

Hookworms in the wrong host

What is the incubation period for cutaneous larva migrans?

7–10 days

What disease related to cutaneous larva migrans develops after swimming in filariaform-infested waters?

Swimmer’s itch

How is cutaneous larva migrans treated?

Topical or oral thiabendazole

(will spontaneously resolve but is very annoying to the patient)

Two types of bacteria cause the clinical illness known as Ehrlichiosis. Which two bacteria are they?

Anaplasma phagocytophilum

&

Ehrlichia chaffeensis

(Both gram-negative intracellular coccobacilli)

What makes the two Ehrlichia bacterial species so unusual?

They live within the phagosomes of immune cells

Which TWO types of immune cells are affected in Ehrlichiosis?

Granulocytes with Anaplasma infection

&

Monocytes with E. chaffeensis infection

Anaplasmosis is an alternative name for which disorder?

Ehrlichiosis due to Anaplasma –

It is also known as human granulocytic anaplasmosis (HGA)

The vector & geographic distribution of disease are the same for Lyme disease & which form of Ehrlichiosis?

Anaplasma phagocytophilum Ehrlichiosis

Geographically, where does the other form of Ehrlichiosis mainly occur?

Southeast, South central, & Midatlantic USA –

Lone Star tick vector (Amblyomma americanum)

What makes the two Ehrlichia bacterial species so unusual?

They live within the phagosomes of immune cells

(Gram-negative, intracellular coccobacilli)

What unusual micro finding is reported after about a week of Ehrlichiosis infection?

Intracellular inclusions in a mulberry or a morula shape – it is lots of tiny bacteria multiplying in the cell!

Diagnostic for Ehrlichiosis!!!

How is Ehrlichiosis acquired?

Tick bite

(In the USA – mainly Ixodes scapularis & pacificus for Anaplasma, Amblyomma for E. chaffeensis)

Is Ehrlichiosis seen outside the USA?

Yes –

The Anaplasma type is seen in Europe & Asia & other species cause Ehrlichiosis elsewhere

What lab abnormalities do you expect to see in the CBC of an Ehrlichiosis patient?

(3)

1. Leukopenia

2. Thrombocytopenia

3. +/− anemia

What non-CBC lab abnormalities are expected in Ehrlichiosis?

(2)

↑ LFTs (usually ALT)

&

Hyponatremia

What is the drug of choice for Ehrlichiosis?

Doxycycline

(at least 7 days – alternative is chloramphenicol)

What other infectious disease sometimes co-occurs with Ehrlichiosis?

Lyme disease

(titers should be sent)

What is the most common chief complaint in children presenting with Ehrlichiosis?

Bad headache

Which patients are at special risk for more severe Ehrlichiosis?

Asplenic & immunocompromised patients

(RMSF-type presentation)

Where does CMV hide when it is in a latent stage?

Peripheral monocytes

What is the hallmark of CMV infection on microscopic exam?

(2)

Very large cells

&

Intranuclear inclusion bodies

In utero CMV infection is the most common cause of which congenital problem?

Congenital deafness

Which body systems can CMV affect – especially in the immunocompromised?

Essentially all of them

What medication may be used to treat CMV?

Ganciclovir

(Foscarnet is second line currently)

Which medication is currently the mainstay for CMV prevention in transplant patients, & in treating CMV retinitis?

Valganciclovir

What effect do CMV medications have on the virus?

They are static only

How common is it for asymptomatic individuals to shed CMV in body secretions?

Very common

In the USA, approximately how common is CMV exposure?

Approximately 50 % of the population

(these individuals often continue to shed the virus)

What is the main problem caused by cryptosporidiosis?

Secretory diarrhea

What is cryptosporidiosis?

A protozoan spread via fecal-oral contamination (human or animal)

Which patients have the greatest difficulty with cryptosporidial infection?

Immunocompromised

&

Kids <5 years

Although there is no entirely effective treatment for cryptosporidiosis, which medication is considered to be the drug of choice?

Nitazoxanide

(used with immunocompromised patients)

(Paromomycin +/− azithromycin is still sometimes used, but is less effective than nitazoxanide)

What unusual source is sometimes the vector of infection for cryptosporidiosis?

Apple cider

(unless it is pasteurized – crypto lives well in apple cider for a month!)

(Remember that EHEC is in apple juice)

How can public or private water supplies be protected from cryptosporidial contamination?

Filtration systems

How is cryptosporidiosis definitively diagnosed?

Oocysts in stool

(often hard to find, must send 3 specimens from 3 different days, minimum)

Which viral group most commonly causes hand–foot–mouth disease?

Coxsackie viruses

What feature of hand–foot–mouth causes the biggest problem?

“Vesiculoulcerative” stomatitis – may produce dehydration

What is the usual pattern for development of hand–foot–mouth diseases?

Oral ulcers,

then,

Papular or vesicular exanthem on hands/feet (non-tender, non-pruritic)

Although lidocaine (viscous) is sometimes given with other ingredients as a mouthwash to relieve oral pain, why can this be a dangerous practice?

Direct absorption from mucous membranes skips the “first pass” effect & can deliver a fairly sizable lido dose

(→arrhythmias)

Which two viruses typically cause a macular rash on the palms & soles?

(unusual pattern!)

Echovirus 16 (Boston exanthem)

&

Coxsackie virus

Where, specifically, does herpes hide when it’s latent (not active)?

Sensory neural ganglia (hence the paresthesias that often precede an outbreak when it starts “creeping out”)

Does neonatal HSV infection require contact with a herpes lesion to develop?

No!

(only 25 % of

mothers with affected infants have a history of or current infection with HSV, and some c/s infants still develop HSV)

Will a patient with herpes encephalitis have skin or mucous membrane/oral lesions?

No

Does c-section delivery prevent transmission of herpes to the neonate?

No

(although it is still standard of care if lesions are present)

What is the buzzword for herpes infection on micro preparation?

Multinucleated giant cells

How is HSV encephalitis definitively diagnosed?

Brain biopsy or PCR of CSF

What will the CSF profile of a patient with herpes encephalitis usually look like?

1. WBC pleocytosis – mainly lymphs

2. High protein

3. High RBCs (even without trauma, due to hemorrhagic necrosis)

Are CSF viral cultures for HSV useful?

Usually not – Often negative even with clear HSV infection

What is the preferred imaging study for suspected HSV encephalitis?

MRI

How are serious herpex simplex infections treated?

IV acyclovir for 21 days

(vidarabine is sometimes added for encephalitis)

Medical professionals are at risk for herpes in unusual locations if they fail to use universal precautions. What is the most common site for the “occupationally exposed” to have a lesion?

Fingertip –

aka “Herpetic Whitlow”

What sport is associated with herpes outbreaks on unusual portions of the body?

Wrestling –

They have many abrasions & pick it up from the mat

What is the most common complication of long courses of acyclovir in young children?

Neutropenia

(25 % with 6 months of use)

Where does Hantavirus come from in nature?

Rodents

How do humans become infected with Hantavirus?

Inhalation of dried excretions/secretions

What age groups are most commonly affected by Hanta pulmonary syndrome, & Hanta infection generally?

Children & healthy young adults

Are the rodents that carry Hantavirus ill appearing?

No – they have a chronic infection

What are the main clinical features of Hanta pulmonary syndrome?

(2)

1. Respiratory failure

(alveoli fill with

protein-rich

fluid)

2. Cardiac depression (low cardiac output with high vascular resistance)

What are the typical activities associated with catching Hanta infection?

Sweeping, cleaning, or construction in a rodent-infested building

What symptoms often occur in the early stages of Hanta infection?

• Fever

• Myalgia & headache

• GI distress

 (n/v/d & pain)

Is cough common in the early stages of Hanta infection?

No – it comes just before the very serious phase (pulmonary edema and cardiac suppression)

Will you see an enlarged cardiac silhouette in Hanta pulmonary syndrome?

No –

The CXR looks like CHF, but this is due to profound leakiness mainly, not cardiac dilation

Which lab values can be a clue to the presence of Hanta, if followed over time?

(3)

1. The platelet count (it falls during the prodrome)

2. Immature WBC forms are seen in the peripheral blood

3. IgM to Hanta will be present

Can Hantavirus spread from person to person?

Generally, no

(one S. American type can, but it is not likely to be on the boards)

If patients survive the shock phase of Hanta pulmonary syndrome, what is the usual prognosis?

Good

(some residual pulmonary problems may persist but they are mild)

What is the usual cause of impetigo?

Staph aureus

What are the two forms of impetigo?

Bullous

&

Non-bullous

(this one more likely to be caused by other organisms, mainly GABHS, in addition to S. aureus)

How does impetigo cause infection?

Bacteria invade the skin at points of minor trauma

In Fitz–Hugh–Curtis syndrome, what is the problem with the right upper quadrant?

Perihepatitis

(infection around the liver capsule, not in the liver itself, usually coming from a gyn source)

“Early” infection with Group B Strep produces what sort of neonatal infection?

Sepsis in the first week of life

What factors, related to the birth itself, make Group B Strep infection more likely?

1. Younger age

2. Lower SES

3. Multiple sex partners

4. History of STDS

If microabscesses are seen on the internal organs of a septic newborn, what is the likely cause of the sepsis?

Listeria monocytogenes

If the mother of a septic newborn has had “flu–like symptoms,” what is the likely cause of the infant’s sepsis?

Listeria

If the mother of a septic infant was asymptomatic during pregnancy/delivery, what is the likely cause of the infant’s sepsis?

Group B strep

(don’t forget N. meningitis is also a possibility)

In adolescents, how is PID usually treated?

Inpatient, due to risk to fertility if compliance is poor

(usually gentamicin  +  clindamycin – both meds have “mice” in the name)

Outpatient treatment is also acceptable, if the adolescent meets criteria for outpatient treatment, including likelihood of compliance

How does an osteomyelitis from pseudomonas get started?

Classically, the vignette will be a nail through a sneaker (rubber sole)

Which other patient groups are likely to develop pseudomonal infections?

1. Burn patients

2. Mechanically ventilated (waterborne)

3. CF

4. Leukemia

In otherwise healthy folks, what pseudomonal infection is fairly common?

Otitis externa

Which cephalosporin is frequently used against pseudomonas?

Ceftazidime

A child who becomes sick while staying on a dairy farm (fevers, myalgia) may have what dairy-related disorder?

Brucellosis

Mnemonic:

Picture a cow saying “BRUUUCE” instead of “MOOO!”

An STD  +  arthritis or multiple skin nodules  =  what diagnosis?

Gonorrhea

Arthritis  +  right upper quadrant tenderness in a female  =  what diagnosis?

Gonorrhea –

specifically Fitz–Hugh–Curtis syndrome

Since botulism is caused by a bacterium, why don’t we treat it with antibiotics?

(3 reasons)

1. The toxin is the problem, not the bacteria

2. Killing the spores may result in increased toxin release in the gut (infant botulism)

3. Some antibiotics actually make the effects of the toxin worse

How does botulism cause problems?

It blocks release of Ach

If you give the “tensilon test” to a botulism patient, will it be positive?

No –

it is positive in myasthenia gravis

(tensilon inhibits acetylcholinesterase, but that doesn’t help if there’s no ACh)

How does botulism cause problems for children & adults?

Preformed toxin is ingested (usually from canned goods)

How is infant botulism different from the disorder seen in children and adults?

Spores are ingested, these grow in the gut, then release toxin

(Doesn’t happen in older children, because gut flora prevent significant growth by the botulinum spores)

An infant with poor feeding, ptosis, and/or descending paralysis most likely has what disorder?

Botulism

(even if honey ingestion is not mentioned)

If an infant’s mother has a history of syphilis – properly treated – does the newborn infant require treatment?

No –

but IgG titers should be followed & they should fall over time if the antibodies came from the mom

If a mother is being treated with penicillin for syphilis, will her in utero fetus be treated at the same time?

Yes –

PCN crosses the p la c e n ta!

A newborn with a maculopapular rash, hepatosplenomegaly, and “peeling skin,” is likely to have what disorder?

Syphilis

Which test is more specific and reliable when you are looking for possible syphilis – VDRL or FTA–Abs?

FTA–Abs – (fluorescent treponemal antigen antibodies – this test remains positive for life)

If a patient sustains a “dirty wound,” how do you know whether a tetanus booster is needed?

If it is more than 5 years from the child’s most recent booster (or original immunization) a booster is needed

In addition to obviously dirty wounds, what three other important categories of wounds are considered to be dirty?

1. Crush injuries

2. Burns

3. Frostbite

If a child has a “clean” wound, how do you know whether a tetanus booster is required?

>10 years since last immunization

What bacterium is especially associated with hemolytic uremic syndrome (HUS)?

E . coli

(especially 0157:H7)

Vignettes in which the child has consumed spoiled milk or undercooked beef are likely to involve what bacterium?

E . coli

(Think of that unfortunate fast food incident a few years back . . . in which several children died due to contaminated burgers!)

What is one simple way to differentiate staph scalded skin syndrome from the erythema multiforme group of disorders?

Staph scalded skin should not involve the mucosa

What is toxic epidermal necrolysis (TEN) caused by?

Hypersensitivity reaction (not a toxin) –

usually it’s a reaction to medication

What causes staph scalded skin syndrome?

Exotoxin from particular Staph bacteria

What causes toxic shock syndrome?

Toxin-producing Staph (occasionally strep can do it also)

If you are treating a patient for Strep who is PCN allergic, what other medication can you use?

Clindamycin

What is the drug of choice for tularemia?

Streptomycin

(Gentamicin is an acceptable alternative)

How is tularemia acquired on the boards?

(& how is it acquired in real life?)

Boards – involvement with rabbit meat or skinning

(real life – mainly tick-borne)

Burn patients are especially at risk for what fungal infection?

Candidiasis

Burn patients are especially at risk for what bacterial infection?

Pseudomonas

Patients on TPN are especially likely to develop what fungal infection?

Candidiasis

What virus likes to cause viral meningitis during the summer months?

Enterovirus

(also causes rash & high fever)

If a child has a swollen parotid gland, but is fully immunized, what causes should you think of?

(4)

1. Obstructing stone

2. Bacterial infection (toxic appearance)

3. Viral infection

4. Bulimia, if it’s bilateral

If a child has not completed his or her immunizations, or has come to the country from abroad, and has swollen parotid glands, what disease should you consider?

Mumps

What is the “formal name” for roseola? (it’s often listed this way in answer choices)

HHV–6

(Human herpesvirus type 6)

What is the typical pattern seen in roseola infection (usual clinical course)?

1. 3–5 days’ high fever

2. Maculopapular rash when the fever ends

3. Complete recovery

What is the formal name for the type of measles associated with birth defects?

Rubella – also known as German measles

Mnemonic:

Imagine an infant speaking German wearing a “bell” that hangs over her heart. The bell is to warn others when she’s coming, because she often bumps into things, due to poor vision (cataracts)

If a pregnant mother is found to be measles (rubella) non-immune, should you give the vaccine?

No – it is a live vaccine & can cause problems itself

What two defects are seen most commonly in infants affected by rubella?

PDA (& other heart issues)

&

Cataracts

Regular measles (rubeola) has an average incubation period of one to one–and–a–half weeks. When are patients most likely to be contagious?

5 days before until 5 days after the rash first appears

In what age group is measles (rubeola) most often seen?

Preschool

How is rubeola spread?

Contact with secretions

&

Aerosolized droplets inhaled

Is measles (rubeola) seen in native-born US children?

Yes

What are the buzzwords for the classic measles (rubeola) presentation?

(5)

Fever

Cough

Coryza

Conjunctivitis

Cutaneous rash

(+/− Koplik spots in the mouth)

Should HIV patients receive the MMR (live) vaccine?

Yes – the risk of the diseases is worse than the risk of the immunization

If an infant is exposed to rubeola, what should be done?

(2 steps)

1. Give MMR within 3 days of exposure

 (Mnemonic:

 3 letters in

 MMR means

 you have 3 days)

2. Give immunoglobulin within 6 days of exposure

If an infant has received rubeola immunoglobulin, does that change the protocol for MMR vaccination?

Yes – in addition to the initial vaccine, another dose should be given in 5 months

If a child receives the MMR before he or she is 1 year old, is reimmunization needed?

Yes –

when the child is more than 1 year old

In addition to supportive care, what specific intervention is recommended for a child with measles by WHO, regardless of the country of origin?

Vitamin A

(one dose on two consecutive days, to reduce possible complications)