Neurotoxins

Question 1

Clostridia is what type of bacteria physically?

Answer 1

Gram positive, spore forming rod

Question 2

Why is clostridia so dangerous?

Answer 2

Clostridia is a nightmare because it includes agents of botulism, tetanus, gas gangrene, food poisoning, C-Diff and psuedomembranous colitis

Question 3

What is the difference between botulism in food, wound botulism, and infant botulism?

Answer 3

Botulism food poisoning results from eating food that contains pre-formed toxin.

Wound botulism occurs when toxin is produced by C botulinum organisms contaminating traumatic wounds

Infant botulism is due to a toxin produced by C. botulinum within the GI tract

Question 4

We know that botulinu toxin stops acetylcholine from leaving, but how does it do this?

Answer 4

It is a zinc dependent endoprotease that cleaves a component of the neurosecretory apparatus such as the vesicle-associated membrane protein

Question 5

Symptoms of botulinum poisoning

Answer 5

Dry mouth, difficulty swallowing, visual disturbances, speech difficulties and descending paralysis.

No fever.

Question 6

How do we treat botulinum toxin

Answer 6

Give horse antitoxin, unless it is infant botulinum, then you give human antitoxin antibodies.

Question 7

How does Tetanus work?

Answer 7

Cleaves VAMP and prevents the release of the neurotransmitter glycine from inhibitory interneurons in the spinal cord, leading to the stimulation of muscle contractions and spasms of tetanus

Question 8

Presentation of tetanus

Answer 8

Initial sign is lockjaw (trismus) followed by, after a while, the characteristic facial expression of risus sardonicus.

Patient may have stiffness of the neck, difficulty swallowing, and rigidity of abdominal muscles.

Gradual muscle involvements of other voluntaries, causing them to tonically spaz.