Properties

Pathogenesis

Clinical findings

Laboratory diagnosis

Treatment & Prevention

Gram-positive rods

Obligate anaerobes

Form spores

Transmission:

- spores, widespread in soil, contaminate vegetables & meat.

- badly canned/bottled preserved food without adequate sterilization – green beans, peppers, mushrooms, smoked fish.

- toxin is heat-labile, inactivated by boiling for several minutes.

Botulinum toxin:

- absorbed from gut & carried via blood to peripheral nerve synapses.

- block release of acetylcholine.

- polypeptide encoded by a lysogenic phage.

Descending weakness & paralysis:

- diplopia

- dysphagia

- respiratory muscle failure.

2 clinical forms:

- wound botulism: spores contaminate a wound, germinate & produce toxin at the site.

- infant botulism: organisms grow in gut & produce toxins.

Organism is usually not cultured.

Mice are inoculated with a sample of the clinical specimen & will die unless protected by antitoxin.

Treatment:

- benzylpenicillin

- trivalent antitoxin (types A, B & C)

- respiratory support.

Prevention:

- proper sterilization of canned & vacuum-packed foods.

- discard swollen cans.