Clostridial Diseases

Question 1

Clostridia

Answer 1

Gram +, spore forming, obligaet anaerobic bacilli

Question 2

C. perfringens

Answer 2

Acute benign diarrheal disease
Spores survive cooking temperatures & germinate to yeild vegetative forms, which proliferate when food is allowed to stand w/o refrigeration. Contaminated food contains vegetative clostridia but little preformed enterotoxin.
Vegetative form sporulates in the small bowel where they produce a variety of toxins that are cytotoxic to enterocytes.

Question 3

C. perfringens type C

Answer 3

Necrotizing Enteritis
prodices an enterotoxin that causes necrotizing enterocolitis.
Endemic to New Guinea- children
Green, necrotic pseudomembranes are seenin areas of necrosis and peritonitis.

Question 4

Gas gangerene

Answer 4

Clostridial myonecrosis
Infection that beings in contaminated wounds and spreads rapidly to adjacent tissues..
C. perfringens is the most common cause
Neutrophils are destroyed by myotixin

Question 5

C. tetani

Answer 5

Tetanus-Lock jaw- spastic skeletal muscle contractions
Necrotic tissue create anaerobic conditions for spores to revert to vegetative bacteria and release tetanus neurotoxin- blocks synaptic inhibition & accumulation of Ach in damaged synapses leads to rigidity and spasms of skeletal musculature.

Question 6

C. boulinum

Answer 6

Botulism
Symmetric descending paralysis of cranial nerves, limbs & trunk
Often found in foods that have not been canned properly, providing an anaerobic environment for the vegetative bacteria to grown and produce the neurotoxin, which resists gastric degradation and is readily absorbed from the proximal small bowel.

Question 7

C. dificile

Answer 7

C. dificile Colitis- necrotizing infectrion of the terminal small bowel and colon. Pseudomembranous colitis
Normal flora of colon for some
Often due to antibiotic administration, wiping out normal
Does not invade the colonic mucosa. Produces 2 exotoxins- Toxin A-fluid secretion Toxin B- Directly cytopathic.
Causes diarrhea