PATHOLOGICAL ASPECTS OF HUMAN DEATHS DUE TO VENOMOUS ANIMALS IN BRAZIL

BENVENUTI, L.A.(1)

(1)Laboratório de  Anatomia Patológica do INCOR

Human death due to venomous animals is rare. In Brazil, the most dangerous species are the snakes from the generaBothrops, Crotalus and Micrurus, and the scorpion Tytius serrulatus. The viscerocutaneous form of loxoscelism, the stings of honey bees and the contact with Lonomia caterpillars can produce severe clinical compromise and death. Bothrops venom induces local lesions characterized by acute inflammatory infiltrate, hemorrhage and necrosis, which can secondarily infect, evolving the patient to septic shock and death. Meanwhile, death is usually due to systemic actions of the venom, which promotes hemorrhage, thrombosis and disseminated intravascular coagulation. The venom of the tropical rattlesnake (Crotalus durissust errificus) induces direct myotoxicity and systemic rhabdomyolysis. In severe cases, myoglobinuria is prominent and its toxic action on the renal tubular ephitelium leads to acute tubular necrosis and renal failure. The venom from the snakes of the genus Micrurus (coral snakes) produces neuromuscular blockade due to direct action of its neurotoxins on the end-plate receptors. Death is usually due to acute respiratory failure and asphyxia. Severe envenomation by the scorpion Tytius serrulatus produces cardiac failure, pulmonary edema, shock and may evolve to death, particularly in children. Coagulative myocytolysis is present in the myocardium, probably secondary to the deleterious effect of large amounts of circulating cathecolamines. Death due to the stings of honey bees can be caused by severe anaphylactic reactions or the direct action of the venom. In massive envenomation, rhabdomyolyis, myoglobinuria, renal acute tubular necrosis, hepatocellular necrosis, focal myocardial necrosis, and histopathological features of acute respiratory distress syndrome were described. Viscerocutaneous form of loxoscelism is characterized by intravascular hemolysis, disseminated coagulation and acute tubular necrosis, which may evolve to acute renal failure and death. Contact with Lonomia caterpillars can induce severe coagulopathy, systemic hemorrhagic syndrome and death due to cerebral hemorrhage.

CORRESPONDENCE TO:

Luiz Alberto Benvenuti, Laboratório de  Anatomia Patológica do INCOR, Avenida Dr. Enéas de Carvalho Aguiar 44, São Paulo, SP, CEP: 05403-000, Brasil, Email: anpluiz@incor.usp.br