Clostridial Diseases

Question 1

Clostridia

Answer 1

• G+ spore forming obligate anaerobic bacilli
• form spores in aerobic env
• vegetative division in anaerobic env

Question 2

C. perfringens

Answer 2

• one of most common cause of bacterial food poisoning in world
• acute, benign diarrhea for less than 24 hrs
• spores survive cooking temps

Question 3

C. perfringens Type C

Answer 3

• produces an enterotoxin that causes necrotizing enterocolitis
• usually in children
• green necrotic pseudomembranes are seen in areas of necrosis and peritonitis

Question 4

Gas gangrene

Answer 4

• C. perfringens is most common cause
• necrotizing, gas forming infection beginning in contaminated wounds and spreading to adjacent tissues
• myotoxins destroy cell membrane

Question 5

Tetanus

Answer 5

• C, tetani
• tetanus toxin released and transported through ventral roots of peripheral nerves and release of inhibitory NTs are blocked –> unopposed muscle contraction

Question 6

Botulism

Answer 6

• C. botulinum neurotoxin
• symmetric descending paralysis
• especially resistant to drying and boiling
• affects cholinergic nerve endings at NMJ
• inhibits acetylcholine release

Question 7

C. difficile

Answer 7

• Colitis is necrotizing infection of terminal small bowel and colon
• Abx associated diarrhea, change in intestinal flora allows it to flourish, produce toxin, and damage the colonic mucosa via two exotoxins
  Toxin A - fluid secretion
  Toxin B - cytopathic