Immune-mediated haemolytic anaemia in 110 dogs in Victoria, Australia

Objective   Evaluate the survival and prognostic indicators (i.e. breed predilection, season, blood transfusion, and the prevalence of autoagglutination) of dogs with immune-mediated haemolytic anaemia (IMHA) in Victoria, Australia.
Design   Retrospective study of 110 diagnosed with primary IMHA at the University of Melbourne Veterinary Clinic and Hospital.
Results   In total, 80 of the dogs (72.7%) were discharged from hospital and 48 of 65 (73.8%) dogs available for follow-up were known to be alive at 1 year, giving an overall 1-year survival of 48 (50.5%) of 95 dogs for which survival data were available. Regarding breed, 80 (18.2%) of the 110 dogs were Maltese-breed dogs compared with 81 (7.4%) of 1100 control dogs (P < 0.001). Springer Spaniels (P = 0.02), Hungarian Vizslas (P = 0.02) and Airedale Terriers (P < 0.001) were also over-represented compared with the control sample. There was no evidence of an association between the occurrence of IMHA in dogs and season in this study. Receiving one or more blood transfusions did not affect survival to the time of discharge from hospital. On initial blood smear examination, 57 (51.8%) of the 110 dogs had spontaneous autoagglutination and its presence was associated with decreased survival to discharge from hospital (P = 0.03). Packed cell volume, white cell count, platelet count and serum total bilirubin on admission had no effect on survival to the time of discharge from hospital or 1 year later.
Conclusion   Dogs with IMHA have a guarded prognosis as only half are still alive 1 year after the acute event.