INFECTIONS OF GASTROINTESTINAL TRACT Flashcards
(70 cards)
- live bacteria in food & water are ingested & grows in body.
- then produces toxins that damage host cells
INFECTION
bacterial toxin or poison was ingested fr. food or water
INTOXICATION
- inflammation of mucosal lining of stomach
Gastritis
Establishment of infectious disease in digestive system is:
1.Pharmacologic action
2. Local inflammation
3.Deep tissue invasion
4.Perforation
-inflammation of small intestine
Enteritis
-inflammation of mucosal lining of stomach & small intestine
Gastroenteritis
3 mechanisms of Food poisoning
1.Ingestion of preformed toxin
2.Infection by toxigenic organisms
3.Infection by enteroinvasive organisms
- inflammation of colon (large intestine)
Colitis
- inflammation of liver
Hepatitis
- low-volume, painful, bloody diarrhea
Dysentery
Bacterial food poisoning is an illness caused by consumption of food contaminated w/ bacteria or bacterial toxins
Bacterial enterocolitis (food poisoning)
- present in contaminated food.
S/s dev hrs consisting of explosive diarrhea, abd pain. - Staph aureus, Vibrio. Clostridium perfringes
Ingestion of preformed toxin
involves secretory - enterotoxin, dysentery
Infection by toxigenic organisms
- is an inflammation of the lining of the intestines.
- Bacterial are; Escherichia coli, Salmonella sp. Shigella sp,Yersinia enterocolitica, Vibrio cholera, Clostridium perfringes, Clostridium difficile, Bacillus anthracis, Mycobacterium tuberculosis
Gastroenteritis (Diarrhea)
- proliferate, invade, destroy epithelial cells
- dysentery
Infection by enteroinvasive organisms
- is a soil organism; commonly contaminates rice
- When large amounts of rice are cooked and allowed to cool slowly, the _________ spores germinate, and vegetative cells produce toxin during log-phase growth or during sporulation.
B cereus
- gram (+)
- spore-forming bacilli (rods)
- facultative anerobe
- arranged in long-chains (square ends)
- spores in center of nonmotile bacilli.
- Most are Saprophytic (soil, water, air & on vegetation)
Bacillus cereus
- Main Reservoir: SOIL
- Transmission/ Predisposing Factor: Spores germinate in reheated rice, then bacteria produce exotoxins, which are ingested
- with Beta-lactamase- (resistant to penicillin)
- DISEASE: Food poisoning
B. cereus
a) emetic type: Fried rice, occasionally pasta
> Source: Rice
> begins 1–5 hours after ingestion
> appears when food containing pre-formed toxin produced during B. cereus growth is consumed
emetic toxin (vomiting)
toxin is heat-LABILE
> Tx: No antibiotic tx
> Profuse diarrhea w/ abdn’l pain & cramps;
> fever, vomiting uncommon.
> Required. Self limiting.
> Rice should not be Kept warm for long periods
Diarrheal type
b) Diarrheal type- meat Dishes & sauces
> incubation period: 8–24 hrs
> produced when enough B. cereus cells are consumed & microorganism is implanted & grows in small intestine producing the toxin,
enterotoxin (diarrhea)
Heat -stable
> N & V, abdominal cramps, occasionally diarrhea
> recovery w/n 24 hrs (self Limiting)
Emetic form
is uncommon w/ B anthracis but common w/ B cereus & saprophytic bacilli. Gelatin is liquefied, & growth in gelatin stabs resembles an inverted fir tree
Hemolysis
> can grow in foods and cause food poisoning by producing either an enterotoxin (diarrhea) or an emetic toxin (vomiting).
This is due to the way in which it is cooked; it is boiled in large quantities, kept unrefrigerated for several hours, depending on consumer’s demand, before being further processed (fried or heated). During this unrefrigerated storage the microorganism can grow and/or produce the emetic toxin that will not be destroyed or inactivated by a subsequent processing step [
B cereus