Pre‐ and Post‐Transfusion Alloimmunization in Dogs Characterized by 2 Antiglobulin‐Enhanced Cross‐match Tests

BACKGROUND: When dogs are transfused, blood compatibility testing varies widely but may include dog erythrocyte antigen (DEA) 1 typing and rarely cross‐matching. OBJECTIVES: Prospective study to examine naturally occurring alloantibodies against red blood cells (RBCs) and alloimmunization by transfusion using 2 antiglobulin‐enhanced cross‐match tests. ANIMALS: Eighty client‐owned anemic, 72 donor, and 7 control dogs. METHODS: All dogs were typed for DEA 1 and some also for DEA 4 and DEA 7. Major cross‐match tests with canine antiglobulin‐enhanced immunochromatographic strip and gel columns were performed 26–129 days post‐transfusion (median, 39 days); some dogs had an additional early evaluation 11–22 days post‐transfusion (median, 16 days). Plasma from alloimmunized recipients was cross‐matched against RBCs from 34 donor and control dogs. RESULTS: The 2 cross‐match methods gave entirely concordant results. All 126 pretransfusion cross‐match results for the 80 anemic recipients were compatible, but 54 dogs died or were lost to follow up. Among the 26 recipients with follow‐up, 1 dog accidently received DEA 1‐mismatched blood and became cross‐match‐incompatible post‐transfusion. Eleven of the 25 DEA 1‐matched recipients (44%) became incompatible against other RBC antigens. No naturally occurring anti‐DEA 7 alloantibodies were detected in DEA 7− dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: The antiglobulin‐enhanced immunochromatographic strip cross‐match and laboratory gel column techniques identified no naturally occurring alloantibodies against RBC antigens, but a high degree of post‐transfusion alloimmunization in dogs. Cross‐matching is warranted in any dog that has been previously transfused independent of initial DEA 1 typing and cross‐matching results before the first transfusion event.