ID Flashcards
What bacteria is responsible for ecthyma gangrenosum (round, indurated black lesion with central ulceration)?
Pseudomonas
Who to prophylax for meningococcemia (4)?
1) Household contacts
2) Close contacts outside the home
3) Contact with oral secretions
4) Anyone who examined the throat
What prophylaxis for meningococcemia?
Rifampin for children; rifampin, ceftriaxone, cipro, azithro for >18yo
Risk factors for SBP?
Nephrotic syndrome and cirrhosis of liver
Bacteria responsible for SBP?
Enteric flora; in nephrotic syndrome–encapsulated organisms (loss of IgG in urine)
Treatment of SBP?
3rd gen cephalosporin and aminoglycoside
Bacteria responsible for secondary peritonitis?
GNR and anaerobes; consider staph epi in PD patients
Infections that latex agglutination can test for (BINS)?
B (Group B strep)
Influenza, haemophilus
Neisseria meningitidis
Strep pneumo
What is cryptosporidium?
Protozoan causing severe, watery, non-bloody diarrhea mostly in immunocompromised (but also immunocompetent) patients
How long does cryptosporidium diarrhea last?
Self-limiting in immunocompetent (~10 days); much longer in immunocompromised–can be indefinite and resistant to treatment
Treatment for cryptosporidium?
Nitazoxanide or paromomycin+azithro
What is cryptococcus?
Encapsulated yeast causing pulmonary disease and meningitis/meningoencephalitis–think AIDS!
Risk factors for cryptosporidium?
Contaminated pools
Risk factors for cryptococcus?
Exposure to bird-droppings (pigeons)
Treatment of cryptococcus?
Ampho B +/- flucytosine, then fluconazole
Classic CXR finding on active TB?
Hilar adenopathy
Treatment of active TB pulmonary disease?
2 months of RIP (rifampin, INH, pyrazinamide) then 4 months of rifampin and INH
Other sites of TB infection?
Meningitis
Adenitis
Pleuritis
Disseminated (Miliary disease)
Treatment of TB meningitis?
2 months of RIPS (rifampin, INH, pyrazinamide, and streptomycin) then 10 months of rifampin and INH; always use steroids
What is constitutes a positive PPD?
5mm–HIV+, abnormal CXR, close contacts, severely immunocompromised
15mm– >/= 4yo and no risk factors
10mm–everyone else
Presentation of chlamydia trachomatis pneumonia?
Afebrile, staccato cough, tachypnea, +/- eye discharge
Treatment of chlamydia trachomatis conjunctivitis?
PO erythromycin or sulfonamides; NOT topical treatment
Treatment of chlamydia trachomatis pneumonia?
Azithromycin x5 days, erythromycin x14 days
Treatment of chlamydia genital infections?
Azithromycin x1 or doxycycline x7 days
Presentation of chlamydia pneumoniae pneumonia?
> 5yo (usually adolescent), low grade fever, infiltrates, bronchospasm
Presentation of RMSF?
Fevers, myalgias, headache, petechial rash (starts peripheral–>central), May/June
Bug causing RMSF?
Rickettsia rickettsii
Treatment of RMSF?
Doxycycline (even if <8yo)
Other presenting lab abnormalities of RMSF?
Thrombocytopenia and hyponatremia
What other tick-born illness presents like RMSF?
Ehrlichiosis (more likely to have leukopenia and elevated LFTs)
What is Q fever?
Rickettsial illness (Coxiella) causing pneumonia, no rash, spread by inhalation of infected animal particles; not caused by tick bite
The 4 C’s of Coxiella?
Cattle
Cats
Cilled (killed–slaughterhouses)
Conception (exposure to infected animal products during birthing)
Treatment of Q fever and ehrlichiosis?
Doxycycline
Treatment of cat scratch disease?
Supportive mostly; don’t I&D; azithro and rifampin can reduce time to lymph node resolution or in immunocompromised patients
Bacteria and treatment of cellulitis from cat or dog bite?
Pasteurella multocida; Augmentin (Bactrim + clinda if PCN allergic)
Possible infections from HiB?
Meningitis, pneumonia, periorbital cellulitis, pyogenic arthritis, epiglottitis
Treatment of HiB?
Ceftriaxone (meropenem if PCN allergic)
What to use for ppx of HiB close contacts?
Rifampin
Who and how to treat Salmonella gastroenteritis?
Infants <3mo, immunocompromised; treat with ceftriaxone
Presentation of typhoid fever (Salmonella typhi)?
Fever, malaise, HSM, “rose spots” on trunk
Diagnosis of typhoid fever?
3 sets of blood cultures; bone marrow culture is best
Treatment of typhoid fever?
Ceftriaxone, ampicillin, Bactrim, fluoroquinolones based on sensitivity
Types of infections with Pseudomonas?
Pneumonia, sepsis, nail-puncture cellulitis/osteomyelitis, endocarditis (IV drug user), bacteremia in burn patient, ecthyma gangrenosum
Presentation of brucellosis?
Fever, malaise, mylagias, LAD, HSM
Transmission of brucellosis?
Unpasteurized milk and cheest, inhalation (cows, dairy farm), or handling carcasses
Treatment of brucellosis?
Doxy + aminoglycoside or doxy + rifampin or Bactrim + rifampin (high rate of relapse–must use combo)
What virus can be superinfected to cause strep TSS or necrotizing fasciitis?
Varicella
Can strep cellulitis cause rheumatic fever?
No–only post-strep GN (strep throat can cause both)
Why treat strep?
To prevent rheumatic fever (does not prevent post=-strep GN)
Presentation of early onset GBS infection (up to 7 days of life)?
Sepsis, pneumonia, meningitis
Presentation of late onset GBS infection (7 days - 3 months?
Bacteremia, meningitis, osteomyelitis
What give pregnant moms GBS ppx?
Decreases early onset GBS, but not late onset
Who to give GBs ppx to (4)?
1) GBS+ this pregnancy
2) GBS bacteriuria this pregnancy
3) Previous infant with invasive GBS disease
4) Unknown GBS and 18hrs, or intrapartum fever
Diagnosis of botulism?
Organisms and/or toxin in blood or stood
How does botulinum toxin work?
Blocks release of Ach into synapse
Treatment of infantile botulism?
Supportive care or anti-toxin (NO antibiotics)
Treatment of campylobacter?
Azithromycin
Presentation of tularemia (Francisella tularensis)?
Fevers, HSM, LAD, irregular ulcer at site of innoculation
Transmission of tularemia?
Rabbits, transmitted by tick or fly bites
Treatment of tularemia?
Gentamicin, doxycycline, or streptomycin
Presentation of bubonic plague (Yersinia pestis)?
Septicemia (with buboes–large, suppurative, painful LN); pneumonic form; meningeal form
Transmission of bubonic plague?
Wild rodents is reservoir; transmitted by fleas or direct contact; pneumonic form transmitted to bystanders by coughing (bioterrorism)
Geographical difference between tularemia and plague?
Tularemia–midwest (AK, MO, OK)
Plague–desert southwest
Treatment of plague?
Streptomycin (2nd line–gent, doxy, fluoroquinolones)
Presentation of anthrax?
Cutaneous–painless papules->paniless vesicle->painless ulcer->painless black eschar
Treatment of anthrax?
Cipro or doxy (ppx with cipro)
In what patient is rifampin contraindicated?
Pregnant patient (known teratogen)
Treatment of shigella?
Ceftriaxone, cipro, or azithro (all patients should be treated)
Diagnosis of neonatal CMV?
Urine CMV culture in first 3-4 weeks of life
4C’s of CMV?
Chorioretinitis
Cerebral calcifications (periventricular)
Censorineural hearing loss
Culture, urine for dx
(Also thrombocytopenia, blueberry muffin lesions, HSM, jaundice, SGA, microcephaly, seizures, hypotonia)
Infection with blood transfusion (especially pneumonia)?
CMV
Coxsackie B can cause what “-itis”?
Myocarditis
Presentation of mumps?
Fever, headache, malaise, myalgias, swelling of parotid gland and/or testicles
Complications of MUMPS?
Meningitis Underwear (orchitis) Muscle aches Pancreatitis Swelling of the parotid gland
What causes intermittent parotid swelling?
Stone in the salivary gland
Which is more common from mumps–orchitis, meningitis, pancreatitis?
Orchitis
Presentation of congenital rubella infection?
Cataracts, glaucoma, hearing loss, PDA, thrombocytopenia, blueberry muffin lesions, HSM, hepatitis
What are blueberry muffin lesions?
Extramedullary hemotopoiesis
Presentation of measles?
Cough, coryza, conjunctivitis, fever, Koplik spots, rash at hairline
Who should get measles immunoglobulin?
Infants <12 months, pregnant women, immunocompromisde individuals (give within 6 days of exposure)
Does delivery via C-section rule out HSV transmission with active infection?
NO–can still be transmitted as ascending infection (although it does decrease the risk)
Best test for HIV in children 18 months and younger?
HIV DNA by PCR
When to test for HIV after exposure?
At exposure, 6 weeks, 12 weeks, and 6 months
Presentation of childhood HIV?
Recurrent bacterial infections, recurrent or persistent thrush, HSM, FTT, DD, cognitive impairment
When to screen infants for HIV (with PCR)?
Birth, 2 months, 4 months, and 6 months
Buzzword for PCP on CXR?
Ground glass opacities or appearance
What vaccines to give kids with HIV?
All except live viruses
Complications of VZV infection?
Secondary bacterial infection (staph and strep), pneumonia, encephalitis, transient cerebellar ataxia
What is VZV exposure for a neonate (to treat with VZIG)?
Mom develops VZV between 5 days before delivery through 2 days after delivery (treat with VZIG within 96 hours of exposure)
When are children with VZV contagious?
1-2 day prior to rash until all lesions are crusted over
Treatment for rabies exposure?
Rabies Ig and vaccine within 7 days of exposure
Presentation of ascaris lumbricoides (parasite)?
Returning from endemic area, abdominal pain, bowel obstruction (travel through GI to blood to lungs then are swallowed)
Treatment of ascaris lumbricoides?
Albendazole, mebendazole, or ivermectin
Non-dysentery presentation of entamoeba histolytica?
Liver abscess, brain abscess, lung disease
Treatment of entamoeba histolytica?
Iodoquinol, paromomycin, or diloxanide; metronidazole 1st if severe or extraintestinal disease
Presentation of toxocara canis?
1) Visceral larbal migrans–GI symptoms (hepatomegaly and abdominal pain) and respiratory symptoms (wheezing)
2) Ocular larval migrans–visual disturbances
3) Covert toxocariasis–GI symptoms and pruritic rash
- Eosinophilia!
Risk factors for toxocara canis?
Exposure to cat and dogs; preschooler eating dirt
Diagnosis of visceral larval migrans?
ELISA and stool culture (to rule out other infections)
Treatment of toxocara canis?
Mebendazole or thiabendazole
Treatment of schistosomal/liver fluke/tapeworm?
Praziquantel
Treatment of strongyloidiasis?
Ivermectin
Treatment of enterobius vermicularis (pinworms–scotch tape test!)?
Menbendazole, pyrantel pamoate, or albendazole (treat whole family)
Presentation of coccidioidomycosis?
Vague flu-like illness, travel to CA, AZ, or TX
Treatment of coccidioidomycosis?
Amphotericin B or fluconazole
Presentation of aspergillosis?
“Asthmatic” with worsening symptoms despite tx; increased eosinophilias and CXR infiltrates
Who develops invasive aspergillosis?
Immunocompromised patients
Treatment of aspergillosis?
Voriconazole or amphotericin B
Presentation of histoplasmosis?
Flu-like illness; HSM; OH, MO, MS
Transmission of histoplasmosis?
Bird droppings; cave exploration
Treatment of histoplasmosis?
Supportive care for healthy kids; amphotericin B for immunocompromised patients
