Sketchy Micro: Clostridium Botulinum

Question 1

Why are canned foods are a common source of C. botulinum?

Answer 1

Because C. botulinum is an obligate anaerobe, and it needs a sealed-off environment to grow.

(Think of the guy in the corner with the gas mask.)

Question 2

Like Clostridium tetani, C. botulinum is ________________.

Answer 2

spore-forming, Gram-positive rods (think of the mechanical nuts –like walnuts –and the violet background)

Question 3

How is the flaccid paralysis of C. botulinum different from Guillain-Barré syndrome?

Answer 3

GBS is ascending paralysis, while C. botulinum produces a descending paralysis.

Question 4

______________ is an early symptom of C. botulinum toxicity.

Answer 4

Ptosis (like the robots’ drooping eyelids), because botulism starts superiorly

Question 5

True or false: C. botulinum toxin cannot cross the BBB.

Answer 5

True, so the CNS is spared

Question 6

How does the C. botulinum toxin work?

Answer 6

It cleaves snare proteins in excitatory motor neurons.

Question 7

Differentiate the causes of botulism in adults and infants.

Answer 7

Adults: our stomach flora can outcompete the spores, so we have to ingest the preformed toxin (such as from canning)

Infants: their stomachs do not have other bacteria to compete with the C. botulinum spores, so ingesting the spores will cause botulism; spores often hide in honey (think of the baby robot who is floppy after the adult robot oiled him up with honey)