Report of two cases: Rattlesnake venom-induced thrombocytopenia.

We report 2 patients who presented with vasomotor symptoms and severe thrombocytopenia following rattlesnake bites. These symptoms persisted in spite of treatment with antivenin and transfusion of multiple doses of platelets. Thrombocytopenia is a common occurrence in moderate to severe crotaline envenomation. Algorithms suggested for the treatment of rattlesnake envenomation with crotaline-specific antivenin may not reverse the associated thrombocytopenia. The precise mechanism of venom-induced thrombocytopenia (VIT), even in the absence of significant coagulopathy, is unknown. Our experience suggests that, unless spontaneous bleeding occurs, repeated transfusion of fresh frozen plasma and/or platelets may not be indicated.