de Medeiros Carlos R, Barbaro Kátia C, Lira Marcela S, França Francisco O S, Zaher Vera L, Kokron Cristina M, Kalil Jorge, Castro Fábio F M
Instituto Butatan, Hospital Vital Brazil, Av. Vital Brazil 1500, 05503-900 São Paulo, SP, Brazil.
Toxicon. 2008 Mar 15;51(4):672-80. doi: 10.1016/j.toxicon.2007.11.022. Epub 2007 Dec 3.
Since allergic sensitization to snake venom has been reported, anaphylactic reactions to snake venom might be an underestimated factor contributing to fatal snakebites, independently from the toxicity of the venom itself. However, little information is available on the determinants of such reaction. Hence, we studied a group of workers exposed to Bothrops jararaca venom (BJV), in order to clarify the factors related with snake venom allergy. The aim of this work was to investigate the prevalence and predictors of venom allergy among workers exposed to BJV and to confirm the involvement of IgE-mediated mechanisms in this condition. Workers exposed to BJV were assessed for venom allergy using questionnaires and immunological tests. The presence of BJV sensitization was determined through quantification of specific IgE. Allergens were studied using the Western blots and inhibition assays. Of the 67 workers evaluated, 7 (10.4%) presented specific IgE antibodies to BJV. Of those, 6 presented typical symptoms of an IgE-mediated allergic reaction when exposed to BJV. Venom sensitization was associated with length of employment (P=0.042), high levels of total IgE (P=0.034), atopy (P=0.051), and specific tasks, primarily the handling of dried venom (P=0.014). Our observations suggest that exposure to BJV can result in allergic sensitization in snake handlers through IgE-mediated mechanisms. The prevalence rate of this condition appears to be high among these workers, and the handling of dried venom, total IgE level above 100 kU/L, length of employment, and probably history of atopy were predictors of its occurrence.
由于已有对蛇毒过敏致敏的报道，对蛇毒的过敏反应可能是导致致命蛇咬伤的一个被低估的因素，与毒液本身的毒性无关。然而，关于这种反应的决定因素的信息却很少。因此，我们研究了一组接触巴西矛头蝮蛇毒（BJV）的工人，以阐明与蛇毒过敏相关的因素。这项工作的目的是调查接触BJV的工人中蛇毒过敏的患病率和预测因素，并确认IgE介导的机制在这种情况下的作用。通过问卷调查和免疫测试对接触BJV的工人进行蛇毒过敏评估。通过定量特异性IgE来确定BJV致敏的存在。使用蛋白质印迹法和抑制试验研究过敏原。在评估的67名工人中，7人（10.4%）出现了针对BJV的特异性IgE抗体。其中，6人在接触BJV时出现了IgE介导的过敏反应的典型症状。毒液致敏与工作年限（P=0.042）、总IgE水平高（P=0.034）、特应性（P=0.051）以及特定任务有关，主要是处理干毒液（P=0.014）。我们的观察结果表明，接触BJV可通过IgE介导的机制导致蛇类处理者发生过敏致敏。这种情况在这些工人中的患病率似乎很高，处理干毒液、总IgE水平高于100 kU/L、工作年限以及可能的特应性病史是其发生的预测因素。
