Department of Emergency Medicine, University of California, Los Angeles, California.
Department of Emergency Medicine, University of California, Los Angeles, California.
Ann Emerg Med. 2022 Dec;80(6):525-527. doi: 10.1016/j.annemergmed.2022.06.013. Epub 2022 Aug 9.
Rattlesnake envenomation can result in significant cutaneous and hematologic toxicity. While Cotalidae polyvalent immune Fab (ovine) antivenom (marketed as CroFab) was available for years, it is associated with increased late hematologic toxicity compared with its predecessor. Consequently, Crotalidae Immune F(ab') equine antivenom [marketed as Anavip; F(ab')AV] has been recently become available. In this paper, we report a case of a 53 year-old man envenomated on his right hand by a Southern Pacific rattlesnake (Crotalus helleri). Edema was present, and his initial platelets were not able to be measured, prompting the administration of 10 vials of F(ab')AV. Ultimately, he received a total of 52 vials of antivenom, before his platelets peaked at 102,000/μL, 56 hours post envenomation. Within hours, his platelets began to fall again. Ultimately, his platelets reached a post-antivenom nadir of 65,000/μL. He was observed closely as an outpatient without additional antivenom, and ultimately had normalization of his platelets (211,000/μL) 20 days post envenomation. This case is one of the first cases demonstrating an inability to achieve control of the hematologic toxicity following Southern Pacific rattlesnake envenomation after treatment with F(ab')AV.
响尾蛇咬伤可导致严重的皮肤和血液毒性。多年来，虽然已经有 Cotalidae 多价免疫 Fab（羊）抗蛇毒血清（商品名为 CroFab）可用，但与前一代产品相比，它会导致晚期血液毒性增加。因此，最近已经有 Crotalidae 免疫 F(ab')马抗蛇毒血清（商品名为 Anavip；F(ab')AV）可用。在本文中，我们报告了一例 53 岁男性右手被南太平洋响尾蛇（Crotalus helleri）咬伤的病例。存在水肿，且他的初始血小板无法测量，因此给予了 10 瓶 F(ab')AV。最终，在被蛇咬伤后 56 小时，他总共接受了 52 瓶抗蛇毒血清，血小板达到 102,000/μL 的峰值。数小时后，他的血小板又开始下降。最终，他的血小板达到抗蛇毒血清后的最低点 65,000/μL。他作为门诊患者接受了密切观察，未再给予额外的抗蛇毒血清，最终血小板恢复正常（211,000/μL），在被蛇咬伤后 20 天。这是首例在使用 F(ab')AV 治疗后，无法控制南太平洋响尾蛇咬伤后血液毒性的病例之一。
