CLUSTER OF WOUND BOTULISM IN CALIFORNIA - CLINICAL, ELECTROPHYSIOLOGIC, AND PATHOLOGICAL-STUDY

Over a period of 15 months we have seen 6 patients with long-standing history of subcutaneous heroin injections who experienced acute blurre d vision, dysphagia, dysarthria, and generalized weakness. Decreased o r absent deep tendon reflexes, pupillary abnormalities, incremental re sponses to fast repetitive nerve stimulation, and positive serology fo r Clostridia botulinum toxin A were found, but not in all cases. Muscl e biopsies showed variable signs of neurogenic atrophy. In vitro elect rophysiology studies revealed decreased end-plate potentials quantal c ontent, confirming the presynaptic nature of the disorder, Mechanical ventilation was required in 5 patients. Half of the patients were trea ted with polyvalent antitoxiin. Prognosis was favorable, though recove ry was slow. In conclusion, acute bulbar weakness with visual symptoms in patients with subcutaneous heroin abuse strongly suggets the possi bility of wound botulism. High diagnostic suspicion combined with hist ology and in vitro electrophysiology confirmation of presynaptic failu re, especially in seronegative cases, may significantly improve morbid ity. (C) 1997 John Wiley & Sons, Inc.