Scorpion Venom Interactions with the Immune System

Abstract

Scorpion envenomation (SE) is a common medical problem in many countries; it is an important cause ofmorbidity and mortality, especially among children. In certain cases scorpion stings lead to multiorgan failure that may be fatal; the manifestations include acute respiratory distress syndrome and systemic inflammatory response syndrome. Neurotoxins are the most active components ofthe scorpion venom responsible for the toxic effects induced after SE. They induce a massive release of neurotransmitters during stimulation ofsympathetic and parasympathetic ofthe autonomic nervous system. The pathophysiological disturbances caused by scorpion venom are not exclusively assigned to the released neurotransmitters. The activation and release of inflammatory mediators (cytokines, kinins, eicosanoids, reactive oxygen species, and nitric oxide) may also play an important role in the pathophysiology of envenomation after stings and may be responsible for some of the inflammatory manifestations and organ failure. The massive release of these mediators from injured and activated cells promotes the inflammatory response and may be responsible for its exacerbation and its maintenance. The present chapter focuses on the role ofinflammatory mediators and on elucidation ofthe potential mechanisms by which the immune system affects the pathophys- iology following SE. Understanding of involved inflammatory cascade in scorpion envenoming syndromes may have future therapeutic and diagnostic benefits.