B5.020 Diarrheal Pathogens Flashcards
types of manifestations of GI infections
typhoid fever hepatitis dysentery chronic gastritis food poisoning secretory diarrhea
differential for chronic gastritis (peptic and duodenal ulcer)
features: stomach, ab pain, no diarrhea
agents: H. pylori
differential for food poisoning (pre formed toxin)
features: upper GI, nausea and vomiting, rapid onset
agents: staph aureus, bacillus cereus, C. perfringens, C. botulinum (peripheral nerves)
differential for acute infectious secretory diarrhea
features: proximal small bowel, watery diarrhea (no fecal leukocytes)
agents: ETEC, EPEC, EHEC, EAEC, vibrio cholera, rotavirus, norovirus, giardia lamblia, cryptosporidium parvum
differential for acute infectious dysentery
features: colon, fever, pain, blood, mucopurulent diarrhea
agents: campylobacter, salmonella, shigella, yersinia, EIEC, entamoeba histolytica, strongyloides, C.diff
differential for acute infectious diarrhea hemorrhagic colitis
features: colon, pain, diarrhea, grossly bloody stools, HUS
agents: EHEC
differential for typhoid fever
features: entry via small bowel, but systemic febrile illness, monocytic leuocytosis
agents: salmonella typhi, yersinia
differential for chronic diarrhea in immunocompromised pts
features: small bowel, protracted watery diarrhea
agents: crypto, microsporidia, cyclo, CMV, mycobacterium avium
location of secretory gastroenteritis
proximal small intestine
type of illness associated with secretory gastroenteritis
watery diarrhea
stool exam of secretory gastroenteritis
no fecal leukocytes
mechanism of secretory gastroenteritis
enterotoxin or bacterial adherence/ invasion causes a shift in water and electrolyte excretion/absorption
classic secretory gastroenteritis pathogens
vibrio cholera ETEC clostridium perfringens Bacillus cereus s. aureus
location of inflammatory gastroenteritis
colon
type of illness associated with inflammatory gastroenteritis
dysentery
stool exam of inflammatory gastroenteritis
fecal polymorphonuclear leukocytes
mechanism of inflammatory gastroenteritis
bacterial invasion or cytotoxins cause mucosal damage that leads to inflammation
classic inflammatory gastroenteritis pathogens
shigella EHEC salmonella vibrio parahaemolyticus C. diff campylobacter
location of invasive gastroenteritis
distal small intestine
type of illness associated with invasive gastroenteritis
enteric fever
stool exam of invasive gastroenteritis
fecal mononuclear leukocytosis (if pt has diarrhea)
mechanism of invasive gastroenteritis
bacteria penetrate the mucosa and invade the reticuloendothelial system
classic invasive gastroenteritis pathogens
salmonella typhi/paratyphi
Yersinia
