What is the diagnostic yield and clinical impact of diagnostic imaging in dogs diagnosed with immune-mediated hemolytic anemia in Belgium: A Retrospective Study

Immune-mediated hemolytic anemia (IMHA) is common in dogs and according to the ACVIM consensus guidelines is described as associative (aIMHA) or non-associative (naIMHA) depending on whether an underlying cause is identified. The utility of diagnostic imaging (DI: abdominal ultrasound and thoracic radiographs) to screen for underlying causes has been questioned. This study aimed to report the prevalence of aIMHA in dogs as well as the outcome of suspected naIMHA in dogs with or without DI. Medical records from dogs, presented to a university teaching hospital between 2017 and 2023, and diagnosed with IMHA were retrospectively reviewed. Two blinded board-certified internal medicine specialists individually reviewed records and classified patients as aIMHA or naIMHA. If classification was unequivocal, a third internist reviewed the case. For dogs with naIMHA and a minimum follow-up period of 3 months, the chances of being alive were assessed at 3, 6, and 12 months. These dogs were further divided into a first group that received ultrasound and radiographs (DI) and a second group that either received partial (ultrasound or radiographs) or absolutely no DI (noDI). Multivariable logistic regression was applied to compare groups. One hundred and twenty-two dogs with IMHA were identified. The reviewers unanimously classified 7 (5.7%) as aIMHA and 115 (94.3%) as naIMHA. Of the dogs with naIMHA, Shih Tzus were overrepresented (n=15, 13.0%), and follow-up was available for 73 (DI=27; noDI=46), 67 (DI=23; noDI=44) and 59 (DI=20; noDI=39) dogs, at 3, 6 and 12 months, respectively. The chances of being alive were 50.7%, 43.3% and 30.5% at 3, 6 and 12 months, respectively. DI did not significantly affect the chance of being alive at 3, 6 and 12 months (p=0.682, 0.554, 0.522, respectively). In conclusion, Shih Tzus were overrepresented in this study. Performing DI in dogs with naIMHA did not affect the chance of being alive in this cohort of dogs in Belgium. A diagnosis of aIMHA was uncommon in this cohort, which may be due to regional differences. DISCLOSURES No disclosures to report.