Standardization of an enzyme linked immunosorbent assay (ELISA) for detecting circulating toxic venom antigens in patients stung by the scorpion Tityus serrulatus Padronização de um teste imunoenzimático (ELISA) para detectar antígenos tóxicos circulantes do veneno em pacientes picados pelo escorpião Tityus serrulatus

• Published in: Revista do Instituto de Medicina Tropical de São Paulo
• Main Authors: Nilton Alves de Rezende, Mariana Borges Dias, Délio Campolina, Carlos Chavéz-Olortegui, Carlos Faria Santos Amaral
• Format: Article in Journal/Newspaper
• Language: English
• Published: Universidade de São Paulo (USP) 1995
• Subjects: Immunodiagnosis; Scorpion envenoming; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic
• Online Access: https://doi.org/10.1590/S0036-46651995000100011; https://doaj.org/article/3dfccc2bfab24b468a43dba4f79bef17

The sensitivity and specificity of an enzyme-linked immunosorbent assay (ELISA) for the detection of circulating antigens from toxic components of Tityus serrulatus scorpion venom was determined in patients stung by T. serrulatus before antivenom administration. Thirty-seven patients were classified as mild cases and 19 as moderate or severe cases. The control absorbance in the venom assay was provided by serum samples from 100 individuals of same socioeconomic group and geographical area who had never been stung by scorpions or treated with horse antisera. The negative cutoff value (mean + 2 SD) corresponded to a venom concentration of 4.8 ng/ml. Three out of the 100 normal sera were positive, resulting in a specificity of 97%. The sensitivity of the ELISA when all cases of scorpion sting were included was 39.3%. When mild cases were excluded, the sensitivity increased to 94.7%. This study showed that this ELISA can be used for the detection of circulating venom toxic antigens in patients with systemic manifestations following. T. serrulatus sting but cannot be used for clinical studies in mild cases of envenoming since the test does not discriminate mild cases from control patients. Neste trabalho foram determinadas a sensibilidade e a especificidade da técnica imunoenzimática (ELISA) desenvolvida por CHAVÉZ-OLORTEGUI et al. para detectar antígenos circulantes de veneno em pacientes picados po Tityus serrulatus. A média mais dois desvios padrão da observância do soro de 100 pacientes controles foi utilizada como limite entre teste positivo e teste negativo ("cutoff"). A especificidade do ELISA foi igual a 97,0%. A sensibilidade do método, quando incluidos pacientes classificados como casos leves, moderados e graves de escorpionismo, foi de 39,3% e aumentou para 94,7% quando considerados apenas os casos moderados e graves. Estes resultados mostram que o ELISA pode ser utilizado para detecção de antígenos tóxicos circulantes em pacientes com manifestações sistêmicas de envenenamento escorpiônico mas não deve ser ...