Arboreal green pit vipers (genus Trimeresurus) of south-east Asia: bites by T. albolabris and T. macrops in Thailand and a review of the literature

Abstract

In Thailand 29 patients were proved to have been bitten by arboreal green pit vipers: 24 by Trimeresurus albolabris and 5 by T. macrops. They were studied in order to define the clinical effects of envenoming, to characterize the haemostatic abnormalities and assess the efficacy of Thai Red Cross antivenom. T. macrops caused only local painful swelling, neutrophil leucocytosis and thrombocytopenia. T. albolabris caused more severe envenoming with local blistering and necrosis, shock, spontaneous systemic bleeding, defibrination, thrombocytopenia and leucocytosis. There was no evidence of disseminated intravascular coagulation, but fibrinolytic activity was increased. Platelet function was normal. The product of admission venom antigen concentration and the delay between bite and admission was significantly higher in defibrinated patients than in those without severe coagulopathy. Antivenom (5 ampoules intravenously) restored blood coagulability, but there was persistent venom antigenaemia, associated in some cases with recurrent coagulopathy. The literature on bites by south Asian green pit vipers of the genus Trimeresurus is reviewed; these bites are common medical problems and causes of morbidity. The identification of individual species is difficult, but may be important if antivenom is to be improved and used appropriately.

Venomous snakebites and antivenom treatment according to a protocol for pediatric patients in taiwan

“…Snakebite injuries are not uncommon in Asia (1)(2)(3)(4). However, reports of their clinical features and management in children are scarce, even in countries known to present a high snakebite incidence (5,6).…”

Neurological Involvement and Hepatocellular Injury Caused by a Snake With Hematotoxin Envenomation

“…Moreover, symptoms can recur in patients bitten by vipers because of slow absorption of the venom from the wound, as seen in this patient. 3,17 In addition, this patient had severely prolonged coagulation tests while his platelet count was relatively normal. These results were compatible with the kinetic study of venom antigen of green pit viper that showed early prolongation of coagulation test but delayed thrombocytopenia.…”

TA-2, a thrombin-like enzyme from the Chinese white-lipped green pitviper (Trimeresurus albolabris)

“…The main feature of its venom is its high proteolytic activity which is thought to be responsible for most of the local and systemic effects observed following envenoming by this snake [20,38,39]. Some components have been isolated, identified and cloned from the venom of this species in Thailand to understand their effects [20,21,40], but the venom of this same species in China has not been extensively studied and identified, although one component (Chitribrisin, a TLE) was previously cloned in our laboratory [9].…”