Clostridia

Question 1

Describe the microscopic appearance of clostridia bacteria

Answer 1

gram-positive anaerobic bacilli.

Question 2

Which clostridia?

produces α-toxin, a lecithinase, which causes gas gangrene (myonecrosis) and haemolysis

features include tender, oedematous skin with haemorrhagic blebs and bullae

Crepitus may present on palpation

Answer 2

C. Perfringens

Question 3

What clostridia?
Is typically seen in canned foods and honey

prevents acetylcholine (ACh) release leading to flaccid paralysis

Answer 3

C. botulinum

Question 4

Which clostridia?
causes pseudomembranous colitis, typically seen after the use of broad-spectrum antibiotics

produces both an exotoxin and a cytotoxin

Answer 4

C. Difficile

Question 5

Which clostridia?
produces an exotoxin (tetanospasmin) that prevents the release of glycine from Renshaw cells in the spinal cord causing a spastic paralysis

Answer 5

C. Tetani