Botulism is a disease caused by clostridium botulinum (gram positive bacillus) which results in a descending, symmetrical flaccid paralysis. This is caused by blocking acetylcholine release from the presynaptic membrane.
The main causes of botulism are either via food (classically canned food) or by wound infection (most frequently in heroin users)
Clinical features of botulism include:
- Cranial nerve palsies (the first sign)
- Blurred vision/diplopia
- Dsyarthria
- Ptosis
- Descending flaccid paralysis
- Respiratory arrest
Sensory pathways are unaffected and intellectual function is preserved.
Routine/’normal’ lab tests are not useful for diagnosis of botulism but can be helpful to rule out differential diagnosis. For example, CSF may be helpful to distinguish botulism from Guillain-Barre syndrome – CSF protein is normal in botulism but raised in Guillain-Barre syndrome. Additionally the tensilon test may also be useful to distinguish botulism from myasthenia gravis; however, borderline positive tensilon tests have occurred in cases of botulism. Confirmation of botulism can be achieved by confirming presence of the toxin.
Treatment is with antitoxin and intensive care.
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