Padronização de um teste de soroaglutinação rápida em látex para diagnóstico de leishmaniose visceral canina.

Abstract

Leishmaniasis is a parasitic disease, zoonotic, and therefore of great importance for public health. The diagnostic tests used by the Ministry of Health showed cross-reactivity and required a long wait time between sample collection, delivery of results and the removal of positive animals , favoring the spread of the disease among dogs and humans. This study aimed to standardize a Rapid Agglutination Test for the diagnosis of canine visceral leishmaniasis, based on the detection of specific antibodies against the recombinant protein HSP70 and comparing the test efficiency with the commercial ELISA kit S7. 416 serum samples were collected and 66 (15.9%) dogs were positive for LVC by ELISA S7. From these were selected 14 positive and 13 negative samples, confirmed by PCR. Selected sera were tested in the latex agglutination assay at dilutions of 1:2, 1:5, 1:8. The sensitivity and specificity was determined by those dilutions and the resulted were: 1:2 dilution, sensitivity 71.0%, specificity 69.0% and the Kappa value of 0.4066; 1:5 dilution, sensitivity 50.0%, specificity 92.0% and the Kappa value of 0.4162; 1:8 dilution, sensitivity 57.0%, specificity 67.0% and the Kappa value of 0.3379. Therefore there was a moderate seroreactivity in the dilutions 1:2 and 1:5. The results demonstrate that the recombinant HSP70 protein of Leishmania chagasi can be used in latex agglutination test because is antigenic, but requires adjustments in the latex sensitization to enhance sensitivity.