ID 5 Flashcards
what is emetic type of b cereus usually caused by? characteristics?
1) rice and pasta
2) nausea and vomiting within 1-5 hours
what causes emetic type of food poisoning caused by b cereus?
Cereulide, a preformed toxin
characteristics of diarrheal type of food poisoning caused by b cereus?
watery, non bloody diarrhea + GI pain within 8-18 hours
rises sardonicus presentation
Raised eyebrows and open grin
tetanus treatment
1) antitoxin +/- vaccine booster
2) diazepam (for muscle spasm)
3) wound debridement
tetanus prophylaxis
tetanus vaccine
floppy baby syndrome?
botulism in babies
what are local botox injections used for?
1) focal dystonia
2) achalasia
3) muscle spasms
sources of botulism
juice and honey
stability of c perfringens toxin?
spores can survive in undercooked food
c perfringens toxin
heat-labile enterotoxin
AB structure of c diff
A = enterotoxin that binds to brush border of the gut B = cytotoxin that causes cytoskeletal disruption via actin depolymerization
what else is c diff associated with?
PPI use
How do you diagnosis c diff?
Detection of one or both toxins in stool by PCR.
diphtheria toxin encoded by…
beta-prophage
other symptoms of diphtheria…
1) myocarditis
2) arrhythmias
appearance of diphtheria on culture?
Black colonies on cystine-tellurite agar
diphtheria diagnosis
1) metachromatic (blue and red) granules
2) elek ttest positive
listeria causes…
1) amnionitis
2) septicemia
3) spontaneous abortion in pregnant women
4) granulomatosis infantiseptica
5) neonatal meningitis
6) meningitis in immunocompromised
7) gastroenteritis in healthy
where is nocardia found?
soil
TB mimic?
nocardia
Nocardia causes
1) pulmonary infection in immunocompromised similar to TB presentation
2) cutaneous infections after trauma in immunocompetent
nocardia treatment
sulfonamides (TMP-SMX)
where is actinomyces found?
Normal oral, reproductive, and GI flora
what else can actinomyces cause?
PID with IUDs
actinomyces treatment
penicillin
Negative PPD means..
1) no infection
2) *sarcoidosis
other TB test?
Interferon-gamma release assay (IGRA)
characteristic findings with secondary TB?
1) caseating granulomas with central necrosis
2) Langerhans giant cells
ghon complex =
Hilar nodes + Ghon focus
what happens after primary TB?
1) over 90% heal by fibrosis and calcification. BUT can reactivate to secondary TB
2) 10% progress (usually in AIDS patients or malnourished people)
Presentation of secondary/reactivated TB?
Fibrocaseous cavitary lesion (usually upper lobes)
what can secondary TB progress to?
1) localized destructive disease with *caseation in kidneys or lungs.
2) OR bacteremia
Where does bacteremic TB infect?
1) meninges
2) vertebra
3) lymph nodes
4) lungs
5) liver
6) spleen
7) adrenal gland
8) joints and long bones
When do you need M avid prophylaxis?
CD4 less than 50
m scrofulaceum causes…
cervical lymphadenitis in children
cord factor appearance
“serpentine cord” appearance
cord factor MOA
Inhibits macrophage maturation + induces release of TNF-alpha
other virulence factor of TB
sulfatides
sulfatides MOA
Inhibit phagolysosomal fusion.
lepromatous leprosy presentation
1) diffuse over skin
2) leonine (lion-lake) facies
3) can be lethal
lepromatous immune response
humoral Th2
tuberculoid immune response
High cell-mediated immunity with a largely Th1-type response
what do you add for lepromatous form?
clofazimine
tuberculoid treatment
dapsone + rifampin
comma-shaped rods?
1) campylobacter
2) cholera
3) h pylori
coccobacilli?
1) h flu
2) pasteurella
3) brucella
4) b pertussis
5) francisella
maltose utilization characteristic of…
n meningitidis
fast lactose fermenters?
1) klebsiella
2) e coli
3) enterobacter
H2S production on TSI agar?
1) salmonella
2) *proteus
mycobacterium leprae characteristics
acid-fast bacillus that likes cool temperatures
