Validation of a cage‐side agglutination card for Dal blood typing in dogs

Abstract

Background Although 98% of the canine population is Dal‐positive, Dal‐negative dogs are more common in some breeds such as Doberman Pinschers (42.4%) and Dalmatians (11.7%), and finding compatible blood for these breeds may be challenging, given limited access to Dal blood typing. Objectives To validate a cage‐side agglutination card for Dal blood typing and determine the lowest packed cell volume (PCV threshold) at which interpretation remains accurate. Animals One‐hundred fifty dogs, including 38 blood donors, 52 Doberman Pinschers, 23 Dalmatians and 37 anemic dogs. Three additional Dal‐positive canine blood donors were included to establish the PCV threshold. Methods Dal blood typing was performed on blood samples preserved in ethylenediaminetetraacetic acid (EDTA) <48 hours using the cage‐side agglutination card and a gel column technique (gold standard). The PCV threshold was determined using plasma‐diluted blood samples. All results were read by 2 observers, blinded to each other's interpretation and to the sample's origin. Results Interobserver agreement was 98% and 100% using the card and gel column assays, respectively. Overall, the sensitivity and specificity of the cards were 86%‐87.6% and 96.6%‐100%, respectively, depending on the observer. However, 18 samples were mistyped using the agglutination cards (15/18 by both observers): 1 false‐positive (Doberman Pinscher), and 17 false‐negative samples including 13 anemic dogs (PCV range, 5%‐24%; median, 13%). The PCV threshold allowing reliable interpretation was determined to be >20%. Conclusions and Clinical Importance Dal agglutination cards are reliable as a cage‐side test, but results should be interpreted cautiously in severely anemic patients.

Delayed haemolytic transfusion reaction in a Lhasa Apso with Dal– blood type

“…Testing for Dal type after its recognition has been available to researchers, and more recently a commercial kit has become available (DMS Laboratories). 14 Dalblood type had been found in many other breeds than Dalmatians, including the Beagle, Cane Corso, Doberman, Lhasa Apso, Mastiff, Pug, Shih Tzu, Whippet and some crossbred dogs. 15,16 Due to the lack of availability of Dal typing in the UK at the time that this case was being managed and more recently, this appears to be the first case and survey to have identified Dalblood type in any breed in the UK.…”

“…Testing for Dal type after its recognition has been available to researchers, and more recently a commercial kit has become available (DMS Laboratories) 14 . Dal– blood type had been found in many other breeds than Dalmatians, including the Beagle, Cane Corso, Doberman, Lhasa Apso, Mastiff, Pug, Shih Tzu, Whippet and some crossbred dogs 15,16 .…”

“…Beside DEA 1 typing kits that have been available for more than two decades, DEA 4 and Dal typing kits, are now commercially available (DMS Laboratories). , 14 The availability of these typing kits allows identification of donors within blood bank programmes who are negative for DEA 1, DEA 4 and Dal antigens. In the meantime, the ongoing support and education of practitioners about the limitations of pre‐transfusion typing and the continued necessity for crossmatching fo more than 4 days after any transfusion is also paramount.…”

Letter regarding “Validation of a cage‐side agglutination card for Dal blood typing in dogs” – Validation of agglutination card kit or simple comparison to gel column method for canine Dal blood typing?

“…To the Editors, Drs. Ver on and Blais from Montreal University recently compared typing results of blood samples from 150 anemic and nonanemic dogs 1 that were obtained with a novel commercial Dal typing agglutination card kit (DMS Laboratories Inc., Flemington, NJ) and a previously reported laboratory gel column method. 2 To further evaluate the ability of the card kit to assess Dal positivity in anemic dogs, they diluted 3 normal samples with their plasma.…”