Micro 7 - Diarrhea Flashcards
What does Enterohemorrhagic E.coli (EHEC)cause?
Bloody diarrhea and severe illness. It produces shiga-like toxin. Can lead to hemolytic uremic syndrome (HUS); anemia, thrombocytopenia, acute renal failure.
What is the treatment for Enterohemorrhagic E.coli (EHEC)?
Supportive.
What type of food is most commonly infected with enterohemorrhagic E.coli (EHEC)?
From infected meat.
What is the most common serotype of Enterohemorrhagic E.coli (EHEC)?
O157:H7.
What does Enterotoxigenic E.coli (ETEC) cause?
Watery diarrhea due to heat-labile and heat stable enterotoxins. Does not infect the intestinal wall and is the most common type of traveler’s diarrhea.
What does Enteropathic E.coli (EPEC) cause?
Produces watery diarrhea, but no toxin produced; the bacteria adhere to the apical surface and flatten the villi, preventing absorption. It is common in children.
What does Enteroinvasive E.coli (EIEC) cause?
Bloody diarrhea and fever die to intestinal wall invasion.
To what other bacteria is Enteroinvasive E.coli (EIEC) related to?
Shigella.
What is the treatment for Enteroinvasive E.coli (EIEC)?
Flouroquinolones, TMP-SMX, azithromycin.
What does Shigella cause and why?
It causes watery diarrhea that turns to bloody diarrhea because it invades the intestinal mucosa, causing inflammation and necrosis.
How is Shigella transmitted? How many of these bacteria are needed to cause disease?
Can spread from person to person contact and contaminated food and water. It is very virulent, only needs 10 of these to cause symptoms.
What is the structural difference between Shigella and salmonella?
Shigella does not have flagella.
How long does Shigella infection last?
From one to two weeks.
Which type of Shigella is associated with Reiter syndrome?
Shigella flexneri.
What does Salmonella cause?
Bloody diarrhea and fever. It is a non-lactose fermenter (like Shigella). The diarrhea begins 1 to 3 days later.
What foods are associated with Salmonella infections?
Egg salads and poultry.
What settings is associated with Salmonella other than foods?
Pet stores, especially turtles.
What can salmonella cause in sickle cell patients?
Osteomyelitis because the salmonella has flagella.
What type of reactive arthritis can salmonella cause?
Reiter syndrome.
What are “rose spots” on the abdomen indicate?
Typhoid fever (Salmonella typhi).
What are four special traits of Campylobacter jejuni?
G(-), Z-shaped, Oxidase positive, and grows in 40C.
What does Campylobacter jejuni cause?
Causes bloody diarrhea, especially in children.
What syndrome is associated with Campulobacter jejuni?
Guillain-Barre syndrome.
What does Vibrio cholerae cause and why?
Watery diarrhea, “rice-water”; it permanently activates cAMP.
What is the treatment for Vibrio cholerae?
Aggressive oral rehydration.
What does Yersinia enterocolitica cause?
Bloody diarrhea and mesenteric adenitis (Can mimic appendicitis).
What does Klebsiella pneumoniae cause?
Normal intestinal flora, but can cause lobar pneumonia when aspirated, especially in people with weakened immune systems. This causes red currant jelly sputum, and necrosis in the lungs. Is a major cause of UTIs.
What does Toxin A of Clostridium difficile do?
Toxin A (AKA enterotoxin), Binds to the brush border of the gut, leads to intestinal fluid secretion and inflammation.
What does Toxin B of Clostridium difficile do?
Toxin B (AKA cytotoxin) causes death of enterocytes by targeting its cytoskeleton. This results in pseudomembranous colitis; necrosis with exudates, fibrin, and leukocytes.
How do we diagnose pseudomembranous colitis and what is the treatment for it?
We test for C.diff toxin in the stool. Treatment is Metronidazole or Vancomycin (orally).
What type of foods are associated with Staph aureus toxin infection?
Meats, mayonnaise, custard and potato salad.
What food is associated with Bacillus cereus?
Reheated rice.
What foods are associated with Vibrio parahaemolyticus and vulnificus?
Shellfish.
What foods are associated with Clostridium botulinum?
Improperly canned foods.
What foods are associated with Clostridium perfringens?
Reheated meat dishes.
What foods are associate with E.coli 0157:H7?
Undercooked contaminated hamburger meat.
What organism would cause food poisoning as a result of mayonnaise sitting out too long?
Staph aureus.
What organism would cause diarrhea caused by G(-) nonmotile organism that does not ferment lactose?
Shigella.
What organism would cause Rice-water stools?
Vibrio cholerae, could be ETEC.
What organism S-shaped organism causes diarrhea?
Campylobacter.
What organism would cause diarrhea transmitted from house hold pets?
Yersinia enterocolitica.
What organism would cause food poisoning resulting from reheated rice (chinese food)?
Bacillus cereus.
What motile G(-) organism causes diarrhea that does not ferment lactose?
Salmonella.
What is the most common cause of “traveler’s diarrhea”?
ETEC.
RFF: Food poisoning due to exotoxin.
Staph aureus and bacillus cereus.
RFF: Osteomyelitis in sickle cell disease.
Salmonella.
