Toxic traveler? Latrodectus species envenomation in Michigan with refractory symptoms after antivenin administration.

A 17-year-old male was envenomated on the right forearm by a black widow spider that had presumably traveled in a packaged dishwasher and been shipped from Mexico to Michigan. The patient experienced vomiting and severe pain in his abdomen and chest approximately 30 min after being bitten. He received 6000 units (1 vial) of Latrodectus antivenin intravenously about 7 h after he was envenomated. He did not experience significant improvement in his symptoms after the administration of antivenin and additional antivenin was not given. The patient was hospitalized for 7 days and still was complaining of intermittent episodes of pain in his chest and lower back 3 weeks after envenomation. To avoid prolonged symptomatology and hospitalization, additional Latrodectus antivenin should be given promptly to those individuals whose symptoms are not ameliorated after 1 vial.