Canine visceral leishmaniosis: a comparative analysis of the EIE-leishmaniose-visceral-canina-Bio-Manguinhos and the IFI-leishmaniose-visceral-canina-Bio-Manguinhos kits.

ABSTRACT

This study evaluated the performance of the EIE-leishmaniose-visceral-canina-Bio-Manguinhos (EIE-LVC) kit and to compare it with that of the IFI-leishmaniose-visceral-canina-Bio-Manguinhos (IFI-LVC) kit. Four groups of dogs were studied group 1 (G1), dogs with clinical signs indicative of CVL and testing positive for the parasite (n = 25); group 2 (G2), dogs with only a presumed diagnosis of CVL (n = 62); group 3 (G3), dogs that had never lived in an area where CVL is endemic and never received a blood transfusion (n = 16); group 4 (G4), dogs carrying other parasites such as babesiosis (n = 4), ehrlichiosis (n = 6) and demodicosis (n = 1). G1 and G3 were used for the calculation of sensitivity and specificity, respectively. The EIE-LVC showed a sensitivity of 72% (IC 95% 50.4-87.1%) and a specificity of 87.5% (IC 95% 60.4-97.8%). The value of the kappa index was 0.975 (CI 95% 0.926-1.024), which represents an excellent fit. For IFI-LVC, the sensitivity was 68.0% (CI 95% 46.4-84.3%) and the specificity 87.5% (CI 95% 60.4-97.8%). When the tests were conducted in parallel, sensitivity was 92.0% (CI 95% 72.5-98.6%) and specificity 75.0% (CI 95% 47.4-91.7%). However, when conducted consecutively, the tests showed a sensitivity of 48.0% (CI 95% 28.3-68.2%) and a specificity of 100.0% (CI 95% 75.9-99.4%). The analysis of clinically suspected dogs using IFI-LVC and EIE-LVC kits in parallel, revealed that 26/62 animals were positive. Cross-reaction was observed in a dog with demodicosis. These results lead to the following conclusions: (1) the performance of the EIE-LVC kit is not statistically different from the IFI-LVC and (2) the kits must be used in parallel if higher sensitivity is required, reducing the number of false-negative results.