Dysphagia can lead to aspiration pneumonia. Muscles of the extremities and trunk and of respiration progressively weaken in a descending pattern. There are no sensory disturbances, and the sensorium usually remains clear. Fever is absent, and the pulse remains normal or slow unless intercurrent infection develops. Routine studies of the blood, urine, and CSF are usually normal.
Constipation is common after neurologic impairment appears.
Major complications include respiratory failure caused by diaphragmatic paralysis and pulmonary infections. Wound botulism is manifested by neurologic symptoms, as in foodborne botulism, but there are no GI symptoms or evidence implicating food as a cause. A history of a traumatic injury or a deep puncture wound in the preceding 2 wk may suggest the diagnosis. Careful search should be made for breaks in the skin and for skin abscesses caused by self-injection of illegal drugs. Cranial nerve deficits typically include ptosis, extraocular muscle palsies, weak cry, poor suck, decreased gag reflex, pooling of oral secretions, and an expressionless face.