Foodborne illness

Question 1

Food poisoning by enterotoxins A-E and G-I

Answer 1

Staphylococcal

Question 2

Resistance of staphylococcal enterotoxins in food poisoning

Answer 2

Heat stable at 100 C for 30 minutes
Resistant to hydrolysis by gastric and jejunal enzymes

Question 3

Superantigen in staphylococcal food poisoning

Answer 3

Enterotoxin B

Question 4

Toxin that causes staphylococcal pseudomembranous enterocolitis

Answer 4

Enterotoxin B

Question 5

Abrupt onset of severe vomiting, nausea, diarrhea, and abdominal pain within 6 hours of eating contaminated food that resolves within 24 hours. Caused by gram positive cocci in clusters.

Answer 5

Staphylococcal food poisoning

Question 6

Gram positive cocci in clusters. Coagulase and catalase positive

Answer 6

Staph aureus

Question 7

Gram positive cocci in clusters. Catalase positive. Coagulase negative. Resistant to novobiocin.

Answer 7

Staph saprophyticus

Question 8

Gram positive cocci in clusters. Catalase positive. Coagulase negative. Sensitive to novobiocin.

Answer 8

S epidermidis

Question 9

Aerobic, spore-bearing, gram positive bacilli arranged end to end.

Answer 9

Bacillus cereus

Question 10

Vomiting and diarrhea starts 1-6 hours after eating contaminated food and lasts for 8-10 hours without fever. Due to preformed heat stable emetic toxic (ETE).

Answer 10

Emetic type of bacillus cereus food poisoning.

Question 11

Diarrhea, nausea, and abdominal cramps start 8-16 hrs after eating food contaminated with spores, lasting up to 48 hours.

Answer 11

Diarrheal type of bacillus cereus food poisoning.

Question 12

Enterotoxins of diarrheal type of bacillus cereus

Answer 12

HBL and Nhe
Heat labile

Question 13

Food poisoning and necrotizing enteritis associated with highly invasive tissue necrosis

Answer 13

C perfringens food poisoning

Question 14

Large gram positive rods with subterminal spore. Spreading colonies with double zone of hemolysis on blood agar.

Answer 14

C perfringens

Question 15

Important toxins of C perfringens

Answer 15

Alpha toxin
Heat labile enterotoxin (CPE)
Beta toxin

Question 16

C perfringens toxin associated with necrotizing activity

Answer 16

Beta toxin

Question 17

Abdominal cramps and watery diarrhea start <12 hours after eating enterotoxin contaminated meat. No nausea, vomiting, or fever. Lasts less than 12 hours.

Answer 17

C perfringens type A food poisoning

Question 18

How to destroy heat labile enterotoxin of C perfringens

Answer 18

Heat food to 74 C

Question 19

Causal agent of enteritis necroticans

Answer 19

C perfringens type C

Question 20

Pt prevents with acute abdominal pain, vomiting, and bloody diarrhea with ulceration and necrosis of small intestine

Answer 20

C perfringens type C

Question 21

Complications of C perfringens type C

Answer 21

Perforation of intestinal wall leading to peritonitis and shock

Question 22

Mortality rate of C perfringens type C

Answer 22

50%

Question 23

Treatment of C perfringens type C

Answer 23

NPO with IV nutrition
Bowel decompression
Resection of necrosed bowel

Question 24

Antibiotics related to C diff

Answer 24

Clindamycin
Ampicillin
Fluoroquinolones
Cephalosporins

Question 25

Toxins produced by C diff

Answer 25

Toxin A/TcdA –> enterotoxin
Toxin B/TcdB –> cytotoxin

Question 26

Complications of C diff

Answer 26

Fulminant colitis
Toxic megacolon
Bowel perforation

Question 27

Endoscopy findings in C diff

Answer 27

Raised yellow plaques
Pseudomembrane

Question 28

Treatment for management of severe diarrhea/colitis in C diff

Answer 28

Metronidazole
Vancomycin

Question 29

Anaerobic, gram positive, endospore forming rod. Produces 7 distinct toxins.

Answer 29

C botulinum