Phase II validation study of the rK39 ELISA prototype for the diagnosis of canine visceral leishmaniasis in Brazil

Abstract

Dogs are the main reservoirs in the domestic transmission cycle of visceral leishmaniasis, and the diagnosis is essential for the effectiveness of the control measures recommended by the Brazilian Ministry of Health. We assessed the diagnostic performance of the ELISA-Vetlisa/BIOCLIN prototype with serum samples from 200 dogs, in triplicate, including symptomatic, oligosymptomatic, asymptomatic, and healthy dogs, originated by two distinct panels (A and B) characterized by parasitological tests as the reference standard. In this study, the prototype kit showed a 99% sensitivity (95%CI: 94.5-100.0) and a 100% specificity (95%CI: 96.4-100.0). The sensitivity of the prototype kit did not vary significantly with the clinical status of the dogs. Considering the final result classification (positive or negative), agreement between the results of repeated tests was almost perfect (kappa = 0.99; 95%CI: 0.98-1.00). ELISA-Vetlisa/BIOCLIN is a promising option for the serological diagnosis of canine visceral leishmaniasis in Brazil.

Understanding hypergammaglobulinemia in experimental or natural visceral leishmaniasis

“…Antibody detection is used in the serological diagnosis of both HVL and CVL. The usual reaction is the detection of specific antibodies by parasite antigens, which can be performed using several methods, among which stand out the ELISA, 13 immunofluorescence reaction 14 and the rapid test 15 …”

“…12 Antibody detection is used in the serological diagnosis of both HVL and CVL. The usual reaction is the detection of specific antibodies by parasite antigens, which can be performed using several methods, among which stand out the ELISA, 13 immunofluorescence reaction 14 and the rapid test. 15 Antibodies seem to be involved in the immunopathology of the disease in both HVL and CVL, possibly due to the presence of immune complexes (IC) that could favour an exacerbated humoral response.…”