Foodborne Botulism Case Studies


"A 31-year old man ate unheated home-canned green chili. One day later he developed blurred vision, dry mouth and limb weakness. On day two he developed respiratory weakness requiring mechanical ventilation, ophthalmoplegia, fixed dilated pupils, facial weakness, dysphagia, tongue and neck muscle paralysis and severe weakness of all limbs, worse proximally than distally. Urinary retention and constipation occurred transiently but the patient had normal bowel sounds and bowel movements had returned before drug treatment was started. Deep tendon reflexes were absent. Sensation and mentation remained normal. The New Mexico State Toxicology Laboratory identified type A botulinum toxin in the patient's stool and from the jar of green chili. Trivalent (A, B, E) equine botulinum antitoxin was administered on day three. Over the next three months, the patient made a slow, steady recovery."5

"On June 30, 1994, a 47-year-old resident of Oklahoma was admitted to an Arkansas hospital with subacute onset of progressive dizziness, blurred vision, slurred speech, difficulty swallowing, and nausea. Findings on examination included ptosis, extraocular palsies, facial paralysis, palatal weakness, and impaired gag reflex. The patient also had partially healed superficial knee wounds incurred while laying cement. He developed respiratory compromise and required mechanical ventilation. Differential diagnoses included wound and foodborne botulism, and botulism antitoxin was administered intravenously. Electromyography demonstrated an incremental response to rapid repetitive stimulation consistent with botulism. Anaerobic culture of the wounds were negative for Clostridium. However, analysis of a stool sample obtained on July 5 detected type A toxin, and culture of stool yielded C. botulinum. The patient was hospitalized for 49 days, including 42 days on mechanical ventilation, before being discharged. The patient had reported that, during the 24 hours before onset of symptoms, he had eaten home-canned green beans and a stew containing roast beef and potatoes. Although analysis of the left-over green beans was negative for botulism toxin, type A toxin was detected in the stew. The stew had been cooked, covered with a heavy lid, and left on the stove for 3 days before being eaten without reheating. No other persons had eaten the stew."7

"During May 4 - 5 [1992], a man of Egyptian descent aged 32 years made three visits to a hospital emergency department because of rapidly progressive problems including dizziness, ptosis, facial drooping, dry mouth, weakness, and respiratory failure requiring mechanical ventilation. On the third visit, myasthenia gravis was diagnosed on the basis ofa positive Tensilon (use of trade names is for identification only and does not imply endorsement by the Public Health Service or the U.S. Department of Health and Human Services) test. On May 6, the patient was transferred to another hospital for treatment of suspected myasthenia gravis; on arrival, he was admitted to intensive care and continued on mechanical ventilation for respiratory failure. Plasmapheresis was performed without improvement in symptoms. Also on May 6, three family members developed blurred vision, ptosis, and dry mouth. A diagnosis of botulism was considered, and the three family members were hospitalized. All four patients received trivalent (types A, B, and E) botulinal antitoxin. NJDH traced the source of botulism to an ethnic preparation of fish known as moloha, an uneviscerated, salt-cured fish product. On May 3, the family consumed moloha reported to have been purchased that day from a local retail fish market. They consumed the moloha without cooking or heating it. Botulinal toxin type E was detected in leftover fish and in a stool specimen from the index patient. A family friend who also ate some of the fish but did not develop symptoms was treated with antitoxin as a prophylactic measure. On May 6, no moloha or similar fish products were found at the market, and the owner denied selling this type of fish. The fish distributors serving this market were contacted, but no source of the fish could be identified. On May 7, NJDH notified all New Jersey acute-care hospitals, public health departments in the New Jersey and Jew York City areas, and the New Jersey Poison Information and Education System of the outbreak and signs and symptoms of botulism. On May 8, the public was alerted through the news media to avoid consumption of moloha and to seek medical care if symptoms of botulism developed. CDC notified state epidemiologists of nearby states of the outbreak. No additional cases were identified."14


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