Breed predispositions, clinical findings, and prognostic factors for death in dogs with nonregenerative immune‐mediated anemia

Abstract

Abstract Background Breed predispositions, survival, and prognostic factors have not been evaluated in dogs with nonregenerative immune‐mediated anemia (nrIMA). Hypothesis/Objectives To describe clinicopathologic variables, evaluate their associations with survival, and determine breed predispositions for dogs with nrIMA. Animals Fifty‐nine client‐owned dogs with nrIMA. Methods Referral hospital records were reviewed retrospectively for dogs with primary nrIMA (PCV ≤30%, corrected reticulocyte percentage (CR%) ≤1.0, bone marrow sampling with evidence of immune‐mediated destruction, and underlying causes excluded). Breed predispositions were evaluated by calculation of odds ratios in a case control study; prognostic factors by logistic regression in a cohort study. Results Fifty‐nine dogs with nrIMA had a median PCV of 12% (interquartile range [IQR]: 10%‐17%) and CR% 0.1 (0%‐0.2%). At least ≥1 ACVIM IMHA diagnostic criteria were met by 35 dogs (59%). Whippets, Lurchers, and miniature Dachshunds were predisposed to nrIMA. Median survival time was 277 days (IQR: 37‐1925), with 3‐ and 12‐month survival rates 61% and 43%, respectively. Erythroid regeneration and remission were achieved by 88% and 62% of dogs, respectively. Corrected reticulocyte percentage >0.2 was associated with improved survival. Conclusion and Clinical Importance Although there is overlap of clinical features between dogs with IMHA and nrIMA, the prognosis for those with nrIMA depends predominantly on the severity of reticulocytopenia.

Keywords

• bone marrow
• CHAOS
• IMHA
• PIMA
• rubriphagocytosis