Efficacy of a latex agglutination test for diagnosing leptospirosis

摘要

Latex particles were adsorbed with a heat resistant antigen extracted from cells of Leptospira interrogans serovars ballum, pyrogenes, canicola, javanica, tarassovi and L. biflexa serovar patoc and used as antigen in a plate test for detecting agglutinins in animals sera. The latex antigens reacted with the homologous antiserum, as well as antisera against each of the above Leptospira serovars. Heterologous reactions were also observed with antiserum against bataviae, copenhagenii, dehong, australis and pomona. Latex adsorbed with ballum antigen was most cross reactive. For studying the efficacy of the latex antigen on field sera, the latex particles adsorbed with a pool of Leptospira antigens were used. As compared to microscopic agglutination test, the sensitivity and specificity of the latex test was satisfactory in dog (89.0 percent and 83.3 percent, respectively) and pig (88.8 percent and 81.2 percent), whereas it was poor with goat (60.0 percent and 77.0 percent). In cattle, the sensitivitywas low (63.0 percent) but the test possessed satisfactory level of specificity (84.0 percent). The study suggests that the latex agglutination test could be employed as a serodiagnostic test in pigs and dogs in those laboratories where facilities for conducting MAT or ELISA do not exist.