Performance of rapid tests for canine visceral leishmaniasis diagnosis in Argentina

SALOMÓN, OD; PEREZ AA; RIARTE A; CASAS N; FRAGUEIRO-FRÍAS V; NEGRI V; SANTINI MS; LIOTTA DJ

MEDICINA (BUENOS AIRES)

MEDICINA (BUENOS AIRES)

Lugar: Buenos Aires; Año: 2020 vol. 80 p. 103 - 110

0025-7680

To diagnose dogs infected by Leishmania infantum rK39 rapid diagnosis test is widely used inthe Americas, while dual path platform (DPP) was recently adopted by Brazil. In this study weassessed the performance of rK39-RDT and DPP tests in recent urban transmission scenarios of Argentina.The sensitivity and specificity were evaluated with a sera panel and field samples, taken as true infected thosefrom parasitological and/or PCR positive tests. Since none of these tests can be taken as a gold standard, theperformance was also evaluated using Latent Class Analysis, a statistical modeling technique which allows toestimating sensitivity and specificity defining a latent class variable as the reference standard. The sensitivityof both tests in the panel was around 92% (symptomatic dogs 96%, asymptomatic 83%), while the sensitivityin field samples of rK39-RDT was 77%, and DPP 98% (mean in symptomatic dogs 89%, asymptomatic 82%).The specificity was similar for both tests and samples, around 98%. Therefore, these tests are acceptable forprogram dog population-based studies, as spatial stratification, focus intervention and follow up, and they couldbe used for individual screening and confirmation of clinical presumptive diagnosis in polysymptomatic dogs.The inability to discriminate between immunity and actual infectiousness suggest that a combination with othernon-immunological based tests will be required for highly sensitive/specific diagnosis in order to targeting controlmeasures in individual reservoirs from public health perspective, as for individual management from animal healthperspective.