Neutralization of bitis parviocula (Ethiopian mountain adder) venom by the south african institute of medical research (SAIMR) antivenom / Neutralização do veneno de Bitis parviocula (serpente da Montanha da Etiópia) pelo antiveneno do Instituto Africano de Pesquisa Médica (SAIMR)

BACKGROUND: The Ethiopian mountain adder (Bitis parviocula) is a viperid known only from a few locations in southwestern Ethiopia. METHODS: a total of 30 µg of B. arietans and B. parviocula venoms were run on a 10-20 percent Tricine gel. To assay lethality dose fifty (LD50), five groups of eight mice for each venom were used. Hemorrhagic activity for crude venom was tested. Fibrinogenolytic activity of crude venom was measured using (2.5 mg/mL) of fibrinogen solution and (0.03 mg/mL) of crude venom. Gelatinase activity of the venom was tested on a Kodak X-OMAT TM film. Crude venoms of B. parviocula and B. arietans were tested for their abilities to affect clotting time, clotting rate and platelet function on whole human blood. RESULTS: The (SAIMR) antivenom was confirmed in this study to neutralize the lethal activity of venom from Bitis parviocula. The ED50s of SAIMR antivenom on B. parviocula and B. arietans neutralized half of 18.2 and 66.7 mg of venom, respectively. The hemorrhagic activities (MHDs) of B. parviocula and B. arietans were 0.88 and 1.7 µg, respectively. Bitis arietans and B. parviocula venoms degradated α and β chains at different times. The γ chains remained unaffected. Bitis parviocula venom did not exhibit gelatinase activity, while B. arietans had a MGD of 6.9 µg. At 3 mg/mL, the crude venoms of B. parviocula and B. arietans did not significantly affect clotting time or clotting rate. CONCLUSIONS: The SAIMR antivenom is very effective in neutralizing the venom of B. parviocula and should be considered in treating envenomations by these snakes.

BACKGROUND: Serpente das Montanhas da Etiópia (Bitis parviocula) é um viperídeo conhecido somente em poucas localizações do sudoeste da Etiópia. MÉTODOS: Um total de 30 µg de veneno de B. arietans e B. parviocula foram corridos em gel de 10 a 20 por cento de tricina. Para se estabelecer a quinquagésima dose de letalidade (LD50) foram usados cinco grupos de oito camundongos para cada veneno. A atividade hemorrágica para o veneno cru foi testada. A atividade fibrogenolítica do veneno cru foi medida usando 2,5 mg/mL de solução de fibrinogênio e 0,03 mg/mL de veneno cru. A atividade de gelatinase do veneno foi testada em um filme KODAK X-OMAT TM. Venenos crus de B. parviocula e B. arietans foram testados no que diz respeito à sua capacidade de afetar o tempo de coagulação, a velocidade de coagulação e a função plaquetogênica em sangue humano total. RESULTADO: o antiveneno SAIMR foi confirmado neste estudo no que diz respeito à neutralização da atividade letal do veneno de Bitis parviocula. ED50s do antiveneno SAIMR sobre a B. parviocula e B. arietans neutralizou metade de 18,2 e 66,7 mg respectivamente do veneno. As atividades hemorrágicas (MHDs) de B. parviocula e B. arietans foram respectivamente 0,88 e 1,7 µg. Os venenos de B. arietans e B. parviocula degradaram cadeias α e β em tempos diferentes. A cadeia Γ permaneceu não afetada. O veneno da B. parviocula não mostrou atividade de gelatinase, enquanto o de B. arietans teve um MGD de 6,9 µg. A nível de 3 mg/mL os venenos crus de B. parviocula e B. arietans não afetaram significantemente o tempo e a velocidade de coagulação. CONCLUSÕES: O antiveneno SAIMR é bastante efetivo para neutralizar o veneno da B. parviocula e deveria ser considerado para o tratamento de envenenamentos por estas serpentes.

Bilateral anterior cerebral artery infarction following viper bite.

The viper is one of India’s most commonly encountered poisonous snakes and envenomation following viper bite usually leads to consumption coagulopathy. Clinical manifestations most frequently include external and internal bleeding. In the setting of viper envenomation, large-vessel thrombosis is a very rare occurrence. Also, bilateral anterior cerebral artery infarction, when unrelated to anatomical abnormalities, subarachnoid haemorrhage, surgery or trauma, itself is an exceedingly rare event. We report a case of a 24-year-old previously healthy man who presented with bilateral anterior cerebral artery infarction following a viper bite. We also present hypotheses that may explain this unusual occurrence. ©

Acidentes por animais peçonhentos: serpentes peçonhetas / Envenomation caused by poisonous animals: poisonous snakes

São abordados aspectos da fisiopatologia, clínica e terapêutica dos envenenamentos humanos, causados por serpentes peçonhentas dos gêneros Bothrops, Crotalus e Micrurus, que ocorrem no sudeste do Brasil. Elaboração de diretrizes para o atendimento dos pacientes na U.E-HCFMRP-USP e reprodução dos princípios para a indicação de soroterapia antiveneno (SAV). Quando aplicada, a SAV deverá ser administrada por via intravenosa, gota a gota, sem diluição, precedida por drogas anti-histamínicas (anti ‘H IND. 1’ e anti ‘H IND. 2’) e corticóides, visando à proteção contra possíveis reações de hipersensibilidade e sem que sejam realizados testes cutâneos previamente

Cerebral infarction in a young male following viper envenomation.

Neurological deficits can occur following viper bite. It is usually due to intracerebral or subarachnoid bleed as a result of depletion of clotting factors. A healthy 21-year old male developed motor aphasia and right hemiplegia within two hours of being bit by a viper. Brain CT scan revealed a left frontal lobe infarction. The possible mechanisms for cerebral infarction in this patient are hypotension, endothelial injury, hypercoagulability and vascular.

Coagulation disorder following viper bite in Orissa.

Forty-three cases of viper bite were studied for coagulation disorder of which 34 (79.1%) cases had bleeding manifestations from one or more sites, haematuria being the commonest (46.5%). Disseminated intravascular coagulation was the predominant coagulation abnormality. Administration of snake venom antiserum resulted in prompt recovery from coagulation disorder. However, natural recovery from coagulation abnormality did occur though took longer time.

Clinicopathological study of acute renal failure following viperine snake bite.

Fifty patients of acute renal failure following Viperine snake bite were studied. Oliguria (100%), local swelling (48%) and bleeding tendencies (42%) were the predominant clinical features encountered. Of the 25 patients in whom detailed coagulation studies were done, 24 patients had disseminated intravascular coagulation (DIC) and 1 had primary fibrinolysis. DIC was commoner with Russell's viper bite (62%) in comparison to Echis carinatus bites (40%). Renal histology obtained in 29 cases revealed tubular necrosis (35%), cortical necrosis (24%) tubular degeneration (17%) and glomerular changes (17%). Ballooning of glomerular capillaries (59%), splitting of glomerular basement membrane (40.7%), swelling of endothelial cells (29.6%), and focal proliferation of mesangial cells (17%) were the significant glomerular changes encountered. 20 (40%) patients succumbed, DIC (50%), irreversible shock (30%) and septicaemia (20%) being the immediate causes of death. Development of oliguria within 24 hours of snake bite and cortical necrosis were associated with higher mortality.