Specific serodiagnosis of canine leishmaniasis by indirect immunofluorescence, indirect hemagglutination, and counterimmunoelectrophoresis

The increased prevalence of leishmaniasis in dogs in Mediterranean countries has necessitated use of a reliable specific method of immunodiagnosis. Research was carried out on 88 dogs, among which were 26 with severe clinical leishmaniasis (group A), 15 with mild signs of disease (group B), and 11 without signs of disease (group C); in addition, 15 were healthy (group D) and 21 were affected with various other diseases (group E). Dogs of groups D and E were used as controls. Infection was confirmed by cultural isolation of the parasite. Serotests that were used included the indirect immune fluorescent (IFAT) and indirect hemagglutination (IHAT) tests and counterimmunoelectrophoresis (CIEP); using these tests, specific antibodies against Leishmania infantum were detected in all 88 dogs. Sensitivity of the IFAT was 100% in dogs of groups A, B, and C; for the IHAT, it was 65.38%, 60%, and 54.5%, respectively, and for CIEP, it was 96.1%, 80%, and 72.7%, respectively. For dogs of groups D and E, specificity of the IFAT and IHAT was 100%, and for CIEP, it was 100% for group-D dogs and 90.5 for group-E dogs. Indirect immunofluorescence appeared to be the most specific and sensitive of the 3 tests.