A Hemolytic Transfusion Reaction due to DEA 4 Alloantibodies in a Dog

A 6-year-old female intact Shih Tzu weighing 6.1 kg was referred to the Washington State University (Pullman, WA) Veterinary Teaching Hospital (WSU-VTH) for nonresponsive immune-mediated hemolytic anemia (IMHA).The dog originally presented to the referring veterinarian's office for lethargy, where IMHA was diagnosed.The dog had a PCV of 6%.A direct Coombs test was not performed, but a slide agglutination test was negative.Results of a coagulation profile and platelet count were normal.Two blood transfusions, each with 180-200 mL of stored packed red blood cells (PCV, approximately 60%), were administered 2 days apart, without crossmatching, with blood from ''universal'' donors (dog erythrocyte antigen [DEA] 1.1 negative, 1.2 negative, 3 negative, 4 positive, 5 negative, and 7 negative).No complications were observed.The PCV increased to 14% after the 1st transfusion and to 27% after the 2nd transfusion.Treatment was initiated after the 1st transfusion with prednisone a (1 mg/kg PO q8h), heparin b (75 IU/kg SC q8h), and gastric protectants (misoprostol c [5 mg/kg q8h], famotidine d [1 mg/kg q24h], and sucralfate e [100 mg/kg q12h]).Thoracic radiographs and an abdominal ultrasound were performed, with no abnormalities detected to explain the IMHA.During the next 10 days, the PCV decreased to 18%, and cyclophosphamide f (2 mg/kg PO q24h for 4 days) was added to the therapy.Four days later, the PCV had decreased to 12%, and the dog was referred to the WSU-VTH.No hemolysis or icterus was observed during this time.On physical examination at the WSU-VTH, the only abnormalities noted were pale mucous membranes and a grade II/VI heart murmur in the left apical area.After a blood transfusion, the murmur was no longer audible and was consequently diagnosed as a physiologic murmur.A CBC showed leukocytosis (35,300/L; reference range, 5,800-11,700/L) with a neutrophilia (23,471/L; reference range, 3,000-7,100/L) and left shift (2,471 bands/ L; reference range, Ͻ300/L) and a normocytic, normochromic anemia with a PCV of 10%.There were 1,520 reticulocytes/L, which was lower than expected for both