NEUTRALIZATION OF LOCAL TISSUE-DAMAGE INDUCED BY BOTHROPS-ASPER (TERCIOPELO) SNAKE-VENOM

Local tissue damage represents a serious consequence of Bothrops asper envenomations. It encompasses a complex series of alterations, includ ing myonecrosis, dermonecrosis, hemorrhage and edema. Due to its rapid development it is difficult to neutralize by antivenoms, especially i f there is a delay in serotherapy. Experimental studies with this veno m and the polyvalent (Crotalinae) antivenom produced in Costa Rica ind icate that antivenom is effective in neutralizing these toxic activiti es when incubated with the venom prior to injection. However, if venom and antivenom are injected independently in mice, neutralization of t hese effects is only partial. Moreover, neutralization is not complete even if homologous or heterologous antibodies are present in the circ ulation before venom is injected. Despite differences in their pharmac okinetic profiles, equine whole IgG and F(ab')(2) antivenoms show simi lar efficacy in the neutralization of edema, hemorrhage and myonecrosi s induced by B. asper venom, suggesting that the use of antivenoms mad e of antibody fragments may not improve neutralization of these effect s. This is due, at least in part, to the fact that microvessel disrupt ion by Venom components favors a similar antibody concentration in the affected tissues. Recent advances in the development of neutralizing substances of rapid diffusion, that could be injected locally in the h eld, may contribute to the neutralization of metalloproteinases and ph ospholipases A(2) In addition, the rapid administration of antivenoms with high antibody titers against locally-acting toxins is very import ant in the treatment of these effects. (C) 1998 Elsevier Science Ltd. All rights reserved.