Application of a direct flow cytometric erythrocyte immunofluorescence assay in dogs with immune-mediated hemolytic anemia and comparison to the direct antiglobulin test.
A direct flow cytometric erythrocyte immunofluorescence assay (FC) was developed and compared with the direct antiglobulin test (DAT) for detection of erythrocyte-bound immunoglobulin (IgG and IgM) and complement (C3) in dogs with immune-mediated hemolytic anemia (IMHA). Tests were performed on erythrocytes from 13 healthy nonanemic dogs and from 13 anemic dogs with IMHA. The FC and DAT were negative for erythrocyte-bound immunoglobulin in all healthy dogs. The FC was negative for erythrocyte-bound C3 in 12 healthy dogs and positive in 1 healthy dog, and the DAT was negative for C3 in all healthy dogs. Of the 13 IMHA dogs tested for erythrocyte-bound IgG, 12 were positive using the FC and 7 were positive using the DAT. Sensitivity for the detection of erythrocyte-bound IgG in the 26 dogs was 92% for FC and 53% for DAT. Specificity for detection of erythrocyte bound IgG for FC and DAT was 100%. The addition of IgM and/ or C3 did not increase the sensitivity for FC or DAT. In this group of dogs, the FC provided a more rapid, cost-effective, sensitive, objective method to quantitate erythrocyte-bound immunoglobulin and/or complement compared with the currently used DAT.
Quigley
K A
KA
Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada.
Chelack
B J
BJ
Haines
D M
DM
Jackson
M L
ML
D000743:Anemia, Hemolytic / Q000175:diagnosis / Q000276:immunology / Q000662:veterinary*; D000818:Animals; D003298:Coombs Test / Q000662:veterinary; D004283:Dog Diseases / Q000175:diagnosis* / Q000276:immunology; D004285:Dogs; D004912:Erythrocytes / Q000276:immunology; D005434:Flow Cytometry / Q000662:veterinary*; D007074:Immunoglobulin G / Q000032:analysis*; D007075:Immunoglobulin M / Q000032:analysis*; D011951:Receptors, Complement; D012680:Sensitivity and Specificity
D007074:Immunoglobulin G; D007075:Immunoglobulin M; D011951:Receptors, Complement