Clinical trial of two antivenoms for the treatment of Bothrops and Lachesis bites in the north eastern Amazon region of Brazil.

The efficacies of specific Bothrops atrox-Lachesis and standard Bothrops-Lachesis antivenoms were compared in the north eastern Amazon region of Brazil. The main aim was to investigate whether a specific antivenom raised against the venom of B. atrox, the most important Amazon snake species from a medical point of view, was necessary for the treatment of patients in this region. Seventy-four patients with local and systemic effects of envenoming by Bothrops or Lachesis snakes were randomly allocated to receive either specific (n = 38) or standard (n = 36) antivenoms. In 46 cases (24 in the standard antivenom group, 22 in the other) the snake was identified either by enzyme immunoassay or by examination of the dead snake, as B. atrox in 45, L. muta in one. Patients were similar in all clinical and epidemiological respects before treatment. Results indicated that both antivenoms were equally effective in reversing all signs of envenoming detected both clinically and in the laboratory. Venom-induced haemostatic abnormalities were resolved within 24 h after the start of antivenom therapy in most patients. The extent of local complications, such as local skin necrosis and secondary infection, was similar in both groups. There were no deaths. The incidence of early anaphylactic reactions was 18% and 19%, respectively for specific and standard antivenoms; none was life-threatening. Measurement of serum venom concentrations by enzyme immunoassay (EIA) confirmed that both antivenoms cleared venom antigenaemia effectively. EIA also revealed that one patient had been bitten by Lachesis muta, although the clinical features in this case were not distinctive.

Clinical trial of two antivenoms for the treatmentof Bothrops and Lachesis bites in the northeastern Amazon region of Brazil

The efficacies of specific Bothrops atrox-Lachesis and standard Bothrops-Lachesis antivenoms were compared in the north eastern Amazon region of Brazil. The main aim was to investigate whether a specific antivenom raised against the venom of B. atrox, the most important Amazon snake species from a medical point of view, was necessary for the treatment of patients in this region. Seventy-four patients with local and systemic effects of envenoming by Bothrops or Lachesis snakes were randomly allocated to receive either specific (n=38) or standard (n=36) antivenoms. In 46 cases (24 in the standard antivenom group, 22 in the other) the snake was identified either by enzyme immunoassay or by examination of the dead snake, as B. atrox in 45, L. muta in one. Patients were similar in all clinical and epidemiological respects before treatment. Results indicated that both antivenoms were equally effective in reversing all signs of envenoming detected both clinically and in the laboratory. Venom-induced haemostatic abnormalities were resolved within 24 h after the start of antivenom therapy in most patients. The extent of local complications, such as local skin necrosis and secondary infection, was similar in both groups. There were no deaths. The incidence of early anaphylactic reactions was 18% and 19%, respectively for specific and standard antivenoms; none was life-threatening. Measurement of serum venom concentrations by enzyme immunoassay (EIA) confirmed that both antivenoms cleared venom antigenaemia effectively. EIA also revealed that one patient had been bitten by Lachesis muta, although the clinical features in this case were not distinctive.

[Epidemiological and clinical aspects of scorpion envenomation in the region of Santarém, Pará, Brazil]. / Aspectos epidemiológicos e clínicos do escorpionismo na região de Santarém, Estado do Pará, Brasil. citbelem@yahoo.com

This is a descriptive and prospective study on epidemiological and clinical aspects of 72 scorpion accidents admitted to Santarém Municipal Hospital, state of Pará, Brazil, from February 2000 to February 2001. Only 8.3% brought the animal with them, identified as T. cambridgei. The majority of victims were male (83.3%). The mean age and the time of the medical help were respectively 33.6 +/- 18.3 years and 4.6 +/- 3.2 hours. The parts of the body most affected were the superior members (51.5%). Local symptoms occurred in 91.7% cases and systemic manifestations in 98.6% of the accidents. The local symptoms included: paresthesia in 79.2% cases, pain in 52.8% and edema in 26.4%. Among the systemic manifestations neurological disorders predominated in 97.2%, and the symptom of "electric shock" occurred in 88.9% patients. The most common neurological signs were: myoclonia (93%), dysmetria (86.1%), dysarthria (80.6%), and ataxia (70.8%). The accidents were classified as moderate in 76.4% without any serious cases. The specific anti-venom serum was not administered in 32.7% of the moderate cases, due to non-availability of the anti-venom serum at the time of attendance. The victims of scorpion envenomation notified at Santarém, present a different clinical and regional behavior from previous reports in Brazil and Amazonia regions. The predominantly neurological picture has not previously been described in the Brazilian literature.

Aspectos epidemiológicos e clínicos do escorpionismo na regiäo de Santarém, Estado do Pará, Brasil / Epidemiological and clinical aspects of scorpion envenomation in the region of Santarém, Pará, Brazil

Este trabalho é um estudo prospectivo e descritivo dos aspectos epidemiológicos e clínicos de 72 envenenamentos por escorpiöes admitidos no Hospital Municipal de Santarém, Estado do Pará, Brasil, entre fevereiro de 2000 a fevereiro de 2001. Trouxeram o animal 8,3 por cento das vítimas, os quais foram identificados como T. cambridgei. O sexo masculino foi acometido em 83,3 por cento. A idade das vítimas e o tempo para o socorro médico foram respectivamente de 33,6±18,3 anos e 4,6±3,2 horas em média. Os membros superiores foram acometidos em 51,5 por cento dos casos. As manifestações locais estiveram presentes em 91,7 por cento e as sistêmicas em 98,6 por cento dos envenenamentos. Entre os sintomas locais encontramos: parestesia em 79,2 por cento, dor em 52,8 por cento, e edema em 26,4 por cento dos casos. Nas manifestações sistêmicas predominou as queixas neurológicas em 97,2 por cento das vítimas, sendo o sintoma de sensaçäo de "choque elétrico" pelo corpo (88,9 por cento) o mais freqüente. No exame neurológico os sinais mais encontrados foram: mioclonias (93,0 por cento), dismetria (86,1 por cento), disartria (80,6 por cento) e ataxia de marcha (70,8 por cento). Classificou-se como moderados 76,4 por cento dos envenenamentos, sem nenhum caso grave. Deixaram de realizar a soroterapia 32,7 por cento dos casos moderados, por ausência de soro específico no momento do atendimento. O escorpionismo da regiäo de Santarém mostra um comportamento clínico regional diferente daqueles descritos no Brasil e de outros locais da Amazônia e, apresenta uma clínica predominantemente neurológica, ainda näo descrita na literatura brasileira