On October 16, 2007, a possible case of botulism in a 54-year-old heroin injection drug user (IDU) was reported to Public Health. The patient was hospitalized on October 9, 2007, after surgical repair of a hip fracture sustained in a fall. After initial recovery from surgery, the patient developed acute respiratory failure and was intubated. Two days after intubation the patient was noted to have ptosis and bilateral weakness in the upper body and upper extremities. Physical examination of the skin revealed old injection sites but no apparent wound or abscess.

On October 19, laboratory testing of serum identified Clostridium botulinum toxin type A. The positive serum test, combined with negative stool studies for C. botulinum toxin and C. botulinum culture, confirmed the diagnosis of wound botulism. On October 19, 2007, the patient received botulinum antitoxin, facilitated by the CDC in conjunction with Public Health and the patient’s health care provider. Public Health also distributed a brochure on wound botulism to clients at Needle Exchange sites in King County (online at www.metrokc.gov/health/apu/harmred/wound-botulism.htm). As of the end of October, the patient’s strength and cranial nerve impairment were improving but mechanical ventilation was still required.

The last case of wound botulism reported in King County was in November 2004, in a black tar heroin IDU, with laboratory confirmed C. botulinum toxin type A in serum (summary at www.metrokc.gov/health/epilog/vol4411.pdf). In November 2003, Washington State Department of Health issued an alert regarding two probable cases of wound botulism among injecting users of black tar heroin in Pierce and Yakima counties. Wound botulism is transmitted via inoculation of C. botulinum spores during trauma, or via intramuscular injection or snorting of drugs, particularly black tar heroin.

Clinical hallmarks of botulism include ptosis, blurred vision and the ‘four Ds’: diplopia, dysarthria, dysphonia, and dysphagia. These symptoms are followed by symmetric, descending weakness and paralysis. If botulism is suspected, a thorough physical exam for evidence of cellulitis and abscesses, as well as examination of the paranasal sinuses, should be performed. A history of injecting or inhaling black tar heroin should be determined, as well as a diet history to assess the possibility of foodborne botulism. CSF protein is normal in botulism; EMG may help differentiate causes of paralysis. Imaging tests should be completed to rule out other causes of acute neurologic disease, including stroke or hemorrhage. Initiation of treatment with antitoxin should be based on the clinical diagnosis and should not await laboratory confirmation. Because antitoxin can prevent, but not reverse neuromuscular blockade due to botulinum toxin, early treatment with antitoxin is important to prevent progression to respiratory failure, the most frequent cause of death. Wounds suspected of being contaminated with C. botulinum should be widely debrided and irrigated, ideally after the administration of botulinum antitoxin. Anaerobic cultures should be obtained. Mechanical ventilation is the main supportive therapy for severe cases of botulism.

Report suspected cases to Public Health immediately at 206-296-4774. We will: 1) facilitate laboratory confirmation, 2) assist in obtaining antitoxin from the CDC, 3) investigate and when possible remove likely sources of infection, and 4) identify other persons at risk.