Pathology of Snakebite Envenomation

Snakebites are one of the major neglected health problems in the tropics which comprise mostly of the developing and underdeveloped countries. Viper bites are more common than other poisonous snakebites in human beings. The venom of snakes of the family Viperidae, to which the Russell's viper belongs, consists of a mixture of toxic proteins and enzymes which have hemotoxic and necrotizing properties. There is a profound difference in venom composition and enzymatic activity of these snakes found in different geographical locations. This is aptly reflected in mammoth degree of geographic variation in the pathological effects of its venom on human bite victims. The defective blood coagulability and renal failure are widespread. There are other pathological effects which show a strong geographic variation. Bites in Sri Lanka have resulted in neurotoxicity, rhabdomyolysis and intravascular haemolysis. Bites in Burma resulted furthermore in shock and generalized capillary permeability, whereas bites in Thailand resulted mostly in intravascular haemolysis and reduced coagulability. Pituitary hemorrhage and bleeding in the subarachnoid space has been reported after a bite by Russell's viper in Southern India and in Burma. The death is most protracted in viper bites from massive cerebral and retroperitoneal bleeding. The present paper reviews the variations in snakebite manifestations and highlights on the pathology of envenomation resulting from snakebites and its management.