Performance of laboratory ELISA and rapid ELISA tests for Ehrlichia spp. and Anaplasma spp. antibody detection in dogs

Abstract

The aim of the study was to compare the performance of two diagnostic approaches for the detection of antibodies against Ehrlichia canis (E. canis) and Anaplasma phagocytophilum (A. phagocytophylum). Two types of tests were used. Anti-E. canis ELISA Dog (IgG) and Anti-A. phagocytophilum ELISA Dog (IgG) are ELISA kits for the detection of relevant antibodies in laboratory conditions, and SNAP® 4Dx Plus is a pet-side ELISA-based serological screening test for simultaneous detection of antibodies against A. phagocytophilum/A. platys, E. canis/E. ewingii, B. burgdorferi and Dirofilaria immitis antigens. A total of 61 blood samples obtained from dogs with clinical signs and haematological changes suspect for granulocytic anaplasmosis or monocytic ehrlichiosis were analysed. Antibodies against E. canis were found out in 29 (47.54%) and A. phagocytophilum in 7 (11.48%) of the samples tested by laboratory ELISA. When using the SNAP test, the results were 35 (57.38%) and 11 (18.03%), respectively. Using the laboratory ELISA kit, 18 samples (29.50%) were positive for antibodies against both pathogens vs 9 (14.75%) samples tested by SNAP. The comparison of the two tests showed a greater agreement of the results in the detection of antibodies against Ehrlichia spp. (52 samples) than against Anaplasma spp. (44 samples). This difference was attributed to possible cross-reactions