Gastroenteritis Flashcards
Which gastroenteritis bugs have a 1-6 hr incubation?
Staph aureus and bacillus cereus
Which GI bugs have a 8-14 hr incubation?
Clostridium perfringens
Bacillus cereus
Which bugs have a 16 hour incubation or longer?
- cholera
- vibrio parahemolyticus
- ETEC
- Salmonella
- Shigella
Common food to get ETEC
salad
Easy way to get vibrio parahemolyticus
oysters/shellfish
Easy way to get C perfringens:
beef/poultry
Easy way to get shigella
Potato/egg salad,
Raw veggies
What population is at greater risk for shigella?
MSM and daycare populations
What can cause gastroenteritis in a pregnant woman?
Listeria
HepE
What does non-inflammatory diarrhea (toxin mediated) look like?
Affects the proximal small bowel
Watery stool with no WBCs
What does inflammatory diarrhea look like?
Affects the colon
bloody/mucoid appearance
Fecal WBC is elevated
What are some bugs that cause inflammatory diarrhea?
Shigella, salmonella
EHEC/EIEC (NOT ETEC)
C difficile
Campylobacter
What causes penetrating diarrhea?
Salmonella typhi
What is the definition of diarrhea?
3 loose stools in a 24 hr period
At what point is diarrhea considered “persistent”?
14 days
At what point is diarrhea considered chronic?
30 days
When would you want to work up diarrhea?
- bloody
- hypovolemia
- Small volume stool w/ blood/mucus
- Immunocompromised/pregnant (listeria)
- High fever, duration > 48 hrs
- Recent antibiotic use
What can you do to test whether an infectious agent is causing the diarrhea?
- Fecal WBC
- Lactoferrin
- Stool culture (salmonella, shigella, campylobacter, EHEC)
- Ova and parasite screen for crypto, giardia, amoeba
How does norovirus cause disease?
Damages the brush border. Causes NON bloody diarrhea
How is rotavirus released into the body?
Activatino by proteolysis releases subviral particles
How do you diagnose norovirus?
PCR
How do you diagnose rotavirus?
Rapid antigen detection
How do you treat noro/rotavirus?
SUPPORTIVE
How does shigella cause disease
It invades the colonic epithelial cell and causes ulcerations
What is a serious complication of shigella?
Shiga toxin can cause hemolytic anemia
How does s. typhi cause disease
- Penetrates bowel mucosa
- ->lymphatics
- ->bile
- ->GI
What does S typhi look like, clinically?
headache/fever/malaise
Rose spots
T-pulse dissociation
Positive blood cultures
How do you treat s typhi?
Ampicillin
Tmp/SMX
Cipro