Comparison of cross-matching method for detection of DEA 7 blood incompatibility

We compared 3 major cross-match (XM) tests to identify dog erythrocyte antigen (DEA) 7 blood incompatibilities in dogs as a result of anti\u2013DEA 7 antibodies: gel (GEL), standard tube (TUBE) agglutination, and immunochromatography strips (STRIP). Blood samples from 42 dogs were typed for DEA 7; 2 tested DEA 7\u2013positive (DEA 7+). The 40 DEA 7\u2013negative (DEA 7\u2013) plasma samples were cross-matched against the 2 DEA 7+ and 3 DEA 7\u2013 red blood cell (RBC) samples by GEL to identify samples with anti\u2013DEA 7 antibodies. Twenty DEA 7\u2013 plasma samples without and with anti\u2013DEA 7 antibodies were cross-matched with samples of the 2 DEA 7+ RBCs in a double-blind fashion using the TUBE and STRIP XM methods. GEL results were used as the reference method for comparison. To determine relationships between results, 2 7 2 tables were used. Cohen kappa coefficient (\u3ba) was calculated between results of GEL and the other 2 methods. With GEL, 21 of 40 XM tests were positive and 19 of 40 negative for anti\u2013DEA 7 antibodies. The same results were obtained by TUBE, whereas only 1 of 40 XM tests was positive by STRIP. There was a statistically significant relationship between results of GEL and TUBE (p < 0.000) with perfect agreement (\u3ba = 1.000), but not between GEL and STRIP results (p = 1.000) in which agreement was equivalent to chance (\u3ba = 0.0453). The GEL and TUBE XM tests, but not STRIP, are useful methods for identification of DEA 7 incompatibilities caused by anti\u2013DEA 7 antibodies