Snake envenomation: a component based review on hemostatic alterations

Abstract

Considered by the World Health Organization a neglected public health problem, snakebites occur predominantly in tropical areas of Africa, Asia and Latin America. Approximately 2.7 million people worldwide are victims of snakebites each year, of which between 81,000 and 138,000 later die. Among the survivors, about 400,000 have some permanent disability. The entirety of the mechanism responsible for the venom pathophysiology is not completely understood. However, most of the venom toxins affect human hemostasis, as Bothrops venom components, which destabilize endothelium, affect platelet aggregation, blood clotting and fibrinolysis. Such effects are not only components of the clinical picture of patients who have suffered envenomation, but are also directly associated with the severity of the accident. Thus, it is of great importance to understand the main hemostatic alterations observed in envenomation’s by snakes of the genus Bothrops, which is predominant in South America. Therefore, this review describes the hemostatic changes that occur in Bothrops snakebites, to further improve the understanding of the general pathological mechanisms of snake envenomation’s and the correlation between endothelium dysfunction and coagulation/fibrinolysis systems as a result of the interaction of each class of venom components with human hemostasis. This knowledge is crucial for the development of new effective therapeutic approaches, attenuating the severity of snakebites and reducing amputations and deaths. Besides this, a molecular comprehension of the hemostatic alterations caused by each component of Bothrops venoms may help to identify new molecules and targets for therapeutic applications.