Bacterial Diarrhea Microbiology

  1. Watery diarrhea bugs that don’t cause fever:
    • ETEC
    • Vibrio cholerae
    • Staph aureus
  2. Watery diarrhea bugs that causes fever:
    • EPEC
    • Salmonella
    • Vibrio parahamolyticus
    • Norovirus
    • Rotavirus
  3. Of the vomiting and bloody diarrhea bugs: EIEC ______fever, EHEC ______ fever
    • Causes (EIEC)
    • Does not cause (EHEC)
  4. Bugs that causes bloody diarrhea, fever but no vomiting:
    • Campylobacter jejuni
    • Shigella
    • Clostridium difficile
  5. Gram stain/shape of Listeria monocytogenes?
    • Gram positive
    • Coccobacillus
    • (short and chubby)
  6. What is characteristic of Listeria monocytogenes?
    Tumbling motility
  7. Listeria monocytogenes are ______ hemolytic, catalase ______. Facultatively _____
    • Beta
    • Positive
    • intracellular
  8. True/false: Listeria grows in 42 degree temperature
    False; it grows well at cold fridge temperature. 42 degrees is for Campylobacter jejuni
  9. Listeria most common found in the US in these foods:
    • Soft cheeses
    • Deli meat
  10. What is the Listeria toxin?
    Lysteriolysin O
  11. True/false: Listeria can colonize the female genital tract so baby can be infected at birth
  12. Newborn Meningitis and sepsis can be caused by this bug ____
  13. Abortion, stillbirths, premature births are associated with this bug ____
  14. T/F: Listeria is nonmotile
    False; they are motile
  15. How would you diagnose species of listeriosis?
    Sugar fermentation tests
  16. T/F: Meningitis and sepsis caused by listeria does not require treatment
    False; Listera gastroenteritis deos not require treatment, but meningitis and sepsis definitely need it – treat with ampicillin or gentamicin or you’ll die
  17. What are the non-enterobacteriaceae bugs?
    • Vibrio
    • Campylobacter jejuni/coli
  18. Non-enterobacteriaceae are Gram _____. Oxidase _____
    • Gram negative, rods
    • Positive
  19. Which non Enterobacteriaceae is found in water?
    Vibrio cholerae
  20. Which biotypes of V cholerae cause most epidemics?
    • El Tor
    • O 139
  21. T/F: V cholerae are acid resistant, does not take much to cause illness
    False; they are NOT acid resistant, need to ingest millions to cause illness
  22. What is the toxin for Cholera?
    AB toxin
  23. V cholerae has this toxin ________. And it works by stimulation of _____ which causes increase in______, leading to loss of ___________.
    • Adenylate cyclase
    • cAMP
    • fluid and electrolyte loss
  24. T/F: Cholera gene was acquired from a bacteriophage
  25. V. cholerae _____(Does/does not) ferment sucrose. V parahaemolyticus and V vulnificus ____ (does/ does not) ferment sucrose
    • Does
    • Does NOT

    • Vibrio parahaemolyticus is transmitted through ______
    • Ingestion of raw or undercooked seafood, especially OYSTERS
  26. T/F: V cholerae and V parahaemolyticus both have AB toxin
  27. Vibrio vulnificus can cause _____ and lead to _____ in immunocompromised
    • Cellulitis in wound injuries
    • Fatal septicemia
  28. Which Vibrio infection requires immediate antibiotic treatment?
    V vulnificus
  29. T/F: V cholerae requires antibiotic treatment
    False; just fluids and electrolytes
  30. Campylobacter jejuni is gram ______, oxidase _____ and part of the ___ family
    • Positive
    • Rod
    • Positive
    • Non-Enterobacteriaceae
  31. Oxygen use for campylobacter jejuni?
    Microaerophilic – requires less O2 to grow
  32. T/F: Campylobacter jejuni grows at cold fridge temperature
    False; grows at 42 degrees. Cold fridge temp is for Listeria
  33. Which bug is associated with Guillain-Barre?
  34. _______ is associated with meningitis. _____ is associated with Guillan-Barre
    • Listeria
    • Campylobacter
  35. T/F: Campylobacter is associated with shellfish
    False; Campylobacter is found in domestic animals notably puppies. Shellfish is for Vibrio
  36. Which bug is Nalidixic acid resistant?
  37. Campylobacter can be diagnosed from ____
    Blood agar plus antibiotics
  38. True/false: ALL of the Enterobacteriaceae bugs are oxidase NEGATIVE, and facultative anaerobes
    True! Just as the non-enterobacteriaceae ones are oxidase positive
  39. Gram stain/shape of Shigella. What is its motility, lactose fermenting?
    • Gram negative rods
    • Non-motile
    • Non-lactose fermenting
  40. How does Shigella cause enteritis?
    Invades enterocytes and get into macrophages. But they do NOT penetrate into the body
  41. Shigella _____(is/is not) acid resistant. Cholera ______(is/is not) acid resistant
    • Shigella IS acid resistant
    • Cholera is NOT
  42. What are the “4 F’s” in shigellosis transmission?
    • Food
    • Finger
    • Flies
    • Fomites
  43. What is the Shigella antigen?
    O-Antigens (LPS)
  44. Which is the most common Shigella infection in the states?
    S. sonnei (mild disease)
  45. T/F: all strains of Shigella makes the Shiga toxin (enterotoxin)
    False; only some strains make the shiga toxin
  46. Salmonella reservoir:
    Eggs, poultry and humans
  47. Which are the strains of Salmonella found in human?
    • S typhi (tyophoid fever)
    • S paratyphi
  48. 3 types of diseases caused by Salmonella?
    • Enterocolitis (self-limiting)
    • Septicemic (extraintestinal)
    • Enteric fever (typhoid fever)
  49. Turtles! ______. Puppies!______
    • Salmonella
    • Campylobacter
  50. T/F: Salmonella septicemia usually happens with ingestion of raw eggs
    False; it is usually acquired in the hospital
  51. Patients with which condition are at high risk of serious and reoccurring bone infections?
    Sickle-cell patients
  52. How is Salmonella diagnosed?
    Blood culturing. Non-lactose fermenting and H2S production
  53. T/F: Salmonella colonize ileum, cecum, and penetrate intestines, by activating adenylate cyclase
    True; like ETEC and cholera
  54. Treat enteric fever (Casued by Salmonella typhi) with ____
  55. E coli is lactose _______. Salmonella is lactose ______. Shigella is lactose_____. What about V. cholera?
    • Fermenting
    • Non-fermenting
    • Non-fermenting
    • V cholera is SUCROSE fermenting
  56. E coli is Gr______. Motility?
    • Gram negative rod
    • Motile
  57. Which is the strain of E coli that causes Travelers diarrhea?
    ETEC (toxigenic E coli)
  58. What are the exotoxins in toxigenic E coli (ETEC)?
    • LT (heat labile)
    • ST (heat stable)
  59. What is so different about ST (heat stable) ETEC exotoxin?
    It activates GUANYLATE cyclase, increase cGMP; instead of adenylate cyclase and increase cAMP
  60. What is the heat labile (LT exotoxin) of ETEC?
    Works like cholera toxin (AB toxin) – activates adenylate cyclase, increase cAMP
  61. What is EPEC?
    • enteropathogenic E coli. P for Pili!
    • Causes microvilli damage of the small intestine and leads to malabsorption and diarrhea
  62. Which E coli causes malabsorption of the small intestine?
  63. What is EIEC?
    EnteroInvasive E coli. Invades the colon so get bloody diarrhea like Shigella
  64. Which E coli is alike Shigella infection?
    EIEC – bloody diarrhea
  65. What is EHEC?
    • Enterohemorrhagic E coli. Causes Hemorrhagic colitis from eating undercooked beef
    • Destroys villi in Large intestines
  66. Which E coli is likely from undercooked beef or in water contaminated with cattle feces?
  67. Microvilli damage in the small intestine is caused by _____. In the large intestine is ______
    • EPEC
    • EHEC
  68. Which E coli can cause hemolytic uremic syndrome (HUS) in children?
    EHEC. HUS is toxin from EHEC attacking the kidneys
  69. What is the toxin in EHEC that leads to hemolytic uremic syndrome in children?
    Shiga toxin (stx- phage)
  70. True/false: EHEC caused HUS should be treated with antibiotics
    FALSE! Absolutely do NOT give antibiotics to treat this.
Card Set
Bacterial Diarrhea Microbiology
GI Final- Microbiology