Botulism is an acute neurologic disorder that causes potentially life-threatening neuroparalysis due to a neurotoxin produced by Clostridium botulinum. The 3 main clinical presentations of botulism are as follows:
- Infant botulism
- Foodborne botulism
- Wound botulism
Essential update: FDA approves first heptavalent botulism antitoxin
On March 22, 2013, the FDA approved the first botulism antitoxin that can neutralize all 7 known botulinum nerve toxin serotypes. The heptavalent antitoxin is derived from horse plasma and is the only drug available for treating botulism patients over 1 year of age, including adults. It is also the only available drug for treating infant botulism that is not caused by nerve toxin type A or B.[1, 2, 3, 4]
Signs and symptoms
More than 90% of patients with botulism have 3-5 of the following signs or symptoms:
- Nausea
- Vomiting
- Dysphagia
- Diplopia
- Dilated/fixed pupils
- Extremely dry mouth unrelieved by drinking fluids
Generally, botulism progresses as follows:
- Preceding or following the onset of paralysis are nonspecific findings such as nausea, vomiting, abdominal pain, malaise, dizziness, dry mouth, dry throat, and, occasionally, sore throat
- Cranial nerve paralysis manifests as blurred vision, diplopia, ptosis, extraocular muscle weakness or paresis, fixed/dilated pupils, dysarthria, dysphagia, and/or suppressed gag reflex
- Additional neurologic manifestations include symmetrical descending paralysis or weakness of motor and autonomic nerves
- Respiratory muscle weakness may be subtle or progressive, advancing rapidly to respiratory failure
The autonomic nervous system is also involved in botulism, with manifestations that include the following:
- Paralytic ileus advancing to severe constipation
- Gastric dilatation
- Bladder distention advancing to urinary retention
- Orthostatic hypotension
- Reduced salivation
- Reduced lacrimation
Other neurologic findings include the following:
- Changes in deep tendon reflexes, which may be either intact or diminished
- Incoordination due to muscle weakness
- Absence of pathologic reflexes and normal findings on sensory and gait examinations
- Normal results on mental status examination
