Frequency of dog erythrocyte antigen 1 blood group and risk of incompatible transfusion in dogs of different breeds and mongrels from the city of Salvador - BA, Brazil

The dog erythrocyte antigen 1 (DEA 1) is the most immunogenic blood group in dogs, and blood transfusions may trigger some undesirable effects in veterinary patients, which are directly associated with incompatible transfusions. The present study aimed to investigate the frequency of positive DEA 1 blood group in blood donor dogs from a blood bank in Salvador, Bahia, Brazil, and also to calculate the risk of managing incompatible blood in both first and second transfusion. A number of 203 dogs of different breeds, aged between 1 and 8 years, weighing 28 kg, with no degree of kinship and of both sexes in Salvador - BA, Brazil were evaluated to investigate the blood type DEA 1 frequency, by means of chromatography and flow cytometry tests for blood typing. The risk of incompatible blood transfusion in either a first or a second transfusion was also calculated. The frequency of the DEA 1 group ranged from 0% to 100% in various breeds, but with a mean positivity of 62.07% (126/203). And the lowest risk of an DEA 1 negative animal receiving DEA 1 positive blood within the group of animals evaluated was 0.92% at a first transfusion; and the risk of the same animal receiving incompatible blood for the DEA group 1 in the second transfusion was 0.008%. The highest risk of an DEA 1 negative animal receiving DEA 1 positive blood from these animals was 69.12%; and the risk of receiving incompatible blood for DEA 1 was 47.77%. In conclusion, the frequency of the DEA 1 group varied between the studied breeds and the risk of incompatible blood transfusions varies according to donor and recipiente breeds, but this can be overridden if blood typing tests are performed along with the cross-reaction test for compatibility.

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–DEA 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–positive (DEA 7+). The 40 DEA 7–negative (DEA 7–) plasma samples were cross-matched against the 2 DEA 7+ and 3 DEA 7– red blood cell (RBC) samples by GEL to identify samples with anti–DEA 7 antibodies. Twenty DEA 7– plasma samples without and with anti–DEA 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 × 2 tables were used. Cohen kappa coefficient (κ) 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–DEA 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 (κ = 1.000), but not between GEL and STRIP results ( p = 1.000) in which agreement was equivalent to chance (κ = 0.0453). The GEL and TUBE XM tests, but not STRIP, are useful methods for identification of DEA 7 incompatibilities caused by anti–DEA 7 antibodies.