The Serological Diagnosis of Canine Leishmaniasis: Commercial ELISA or in House IFAT?

Abstract

The levels of anti-Leishmania infantum antibodies are relevant with the diagnosis and the follow-up of infected dogs. Both ELISA (Enzyme-Linked Immunosorbent Assay) and IFAT (Indirect Immuno-Fluorescent Antibody Test) may be employed to estimate the antibody levels in dogs, but at present, the correlation between ELISA absorbance and IFAT titer has not been investigated. In this paper, we compared the optical densities obtained with a commercial ELISA, Leiscan® (Laboratorios Dr. Esteve S.A.), versus the titers obtained by in house IFAT. We measured ELISA absorbance of: 44 IFAT negative samples coming from an endemic area; 10 negative samples coming from a non endemic area; 29 samples with an IFAT titer between 1/40 and 1/80; 10 samples with an IFAT titer of 1/160; 9 samples with an IFAT titer of 1/320; 10 samples with an IFAT titer of 1/640; 10 samples with an IFAT titer ≥ of 1/1280.