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Snake bites are life-threatening injuries that can require intensive care. The diagnosis and treatment of venomous snake bites is sometimes difficult for clinicians because sufficient information has not been provided in clinical practice. Here we review the literature to present the proper management of bites by mamushi, habu, and yamakagashi snakes, which widely inhabit Japan and other Asian countries. No definite diagnostic markers or kits are available for clinical practice; therefore, definitive diagnosis of snake-venom poisoning requires positive identification of the snake and observation of the clinical manifestations of envenomation. Mamushi (Gloydius blomhoffii) bites cause swelling and pain that spreads gradually from the bite site. The platelet count gradually decreases due to the platelet aggregation activity of the venom and can decrease to <100,000/mm(3). If the venom gets directly injected into the blood vessel, the platelet count rapidly decreases to <10,000/mm(3) within 1 h after the bite. Habu (Protobothrops flavoviridis) bites result in swelling within 30 min. Severe cases manifest not only local signs but also general symptoms such as vomiting, cyanosis, loss of consciousness, and hypotension. Yamakagashi (Rhabdophis tigrinus) bites induce life-threatening hemorrhagic symptoms and severe disseminated intravascular coagulation with a fibrinolytic phenotype, resulting in hypofibrinogenemia and increased levels of fibrinogen degradation products. Previously recommended first-aid measures such as tourniquets, incision, and suction are strongly discouraged. Once airway, breathing, and circulation have been established, a rapid, detailed history should be obtained. If a snake bite is suspected, hospital admission should be considered for further follow-up. All venomous snake bites can be effectively treated with antivenom. Side effects of antivenom should be prevented by sufficient preparation. Approved antivenoms for mamushi and habu are available. Yamakagashi antivenom is used as an off-label drug in Japan, requiring clinicians to join a clinical research group for its use in clinical practice.

In autumn 2014, with great effort by the Ministry of Health, Labour and Welfare, the research group will obtain several vials of redback spider (RBS) antivenom for emergency use. However, these small amounts of antivenom are insufficient to cover the demands from majority of hospitals in Japan. The research group carefully discussed the domestic RBS antivenom production by themselves for this emergency. We have now entered the second stage for large-scale antivenom production. Although the domestic production of RBS antivenom has started, great caution is required as we move forward with this plan.

Background: Redback spiders (Latrodectus hasselti) (RBSs) are venomous spiders that have recently spread to Asia from Australia. Since the first case report in 1997 (Osaka), RBS bites have been a clinical and administrative issue in Japan; however, the clinical characteristics and effective treatment of RBS bites, particularly outside Australia remains unclear. This study aimed to elucidate the clinical characteristics of RBS bites and to clarify the effectiveness of the administration of antivenom for treatment., Methods: We performed a retrospective questionnaire survey from January 2009 to December 2013 to determine the following: patient characteristics, effect of antivenom treatment, and outcomes. To clarify the characteristics of patients who develop systemic symptoms, we compared patients with localized symptoms and those with systemic symptoms. We also examined the efficacy and adverse effects in cases administered antivenom., Results: Over the 5-year study period, 28 patients were identified from 10 hospitals. Of these, 39.3% were male and the median age was 32 years. Bites most commonly occurred on the hand, followed by the forearm. Over 80% of patients developed local pain and erythema, and 35.7% (10 patients) developed systemic symptoms. Baseline characteristics, vital signs, laboratory data, treatment-related factors, and outcome were not significantly different between the localized and systemic symptoms groups. Six patients with systemic symptoms received antivenom, of whom four experienced symptom relief following antivenom administration. Premedication with an antihistamine or epinephrine to prevent the adverse effects of antivenom was administered in four patients, which resulted in no anaphylaxis. One out of two patients who did not receive premedication developed a mild allergic reaction after antivenom administration that subsided without treatment., Conclusions: Approximately one third of cases developed systemic symptoms, and antivenom was administered effectively and safely in severe cases. Further research is required to identify clinically applicable indications for antivenom use.

Background: Rhabdophis tigrinus (Yamakagashi snake) is a rear-fanged colubrid snake present throughout Russia and Asia. Its venom induces life-threatening hemorrhagic symptoms and severe disseminated intravascular coagulation with a fibrinolytic phenotype. R. tigrinus antivenom manufactured by the immunization of horses to neutralize the venom has the risk of adverse events such as anaphylaxis and serum sickness disease. It should be used when benefit is greater than the risk of adverse effects; however, its efficacy has not been well evaluated. Although our previous survey of nine cases demonstrated that seven of all cases treated with antivenom survived, the clinical characteristics and prognosis without antivenom administration remained unclear. We assumed that R. tigrinus antivenom administration overlaps self-recovery with supportive care. We aimed to determine the association between antivenom administration and outcome with further analyzed cases., Methods: We retrospectively reviewed the records of the Japan Snake Institute between January 1, 1973 and December 31, 2013. Antivenom and without antivenom groups were compared with regard to baseline demographic features, treatment-related factors, and outcomes., Results: In total, 34 patients were analyzed (97% male, median age 37.5 years). Twenty-five patients were further examined from our previous study. On admission, the median levels of fibrinogen and fibrinogen degradation products were 35 mg/dL and 200 μg/mL, respectively, and platelet counts were 107,000/mm(3). The median disseminated intravascular coagulation score (defined by the Japanese Association of Acute Medicine) was 5. Antivenom was administered to 19 patients, with a median interval of 32 h between bite and antivenom administration. The in-hospital mortality rate was 12%. In univariate analysis, baseline characteristics and laboratory data were not significantly different between the antivenom and without antivenom groups. Hospital mortality in the antivenom group was significantly better than that in the without antivenom group (0% vs. 26.7%, P = 0.03). Moreover, the number of patients developing renal failure requiring hemodialysis was significantly lower in the antivenom group (5.3% vs. 40.0%, P = 0.03)., Conclusions: In our small retrospective study, antivenom administration was likely to be effective in the management of R. tigrinus bites. Apparently, further research is required to confirm its efficacy.

As a response to the recent article by Hifumi et al. published in the Journal of Intensive Care, the present correspondence clarifies the family-level taxonomy of the yamakagashi (Rhabdophis tigrinus). Further, the relevance of the term 'venom-induced consumptive coagulopathy,' instead of disseminated intravascular coagulation, in describing the procoagulant coagulopathy of R. tigrinus is highlighted.

Background: Yamakagashi (Rhabdophis tigrinus) is a species of pit viper present throughout Russia and Eastern Asia. Although R. tigrinus venom is known to induce life-threatening hemorrhagic symptoms, the clinical characteristics and effective treatment of R. tigrinus bites remain unknown. The present study aimed to clarify these issues., Methods: Records in the Japan Snake Institute between 2000 and 2013 were retrospectively investigated. The following were determined: patient characteristics, coagulation and fibrinolytic system abnormalities, effect of antivenom treatment, and outcomes., Results: Nine patients (all males; median age, 38 years) with R. tigrinus bites were identified. On admission, the median levels of fibrinogen and fibrinogen degradation products, and platelet counts were 50 mg/dL, 295 μg/mL, and 107,000/mm(3), respectively. The median (minimum-maximum) disseminated intravascular coagulation (DIC) score defined by the Japanese Association of Acute Medicine was 8 (1-8). Antivenom was administered to seven patients, with a median interval of 35 h between bite and antivenom administration. All patients treated with antivenom survived, and the in-hospital mortality rate was 11%., Conclusions: Patients with R. tigrinus bites presented with DIC of a fibrinolytic phenotype, which can result in life-threatening injury unless appropriate antivenom and DIC treatment are provided.