2016 ACVIM Forum Research Abstract Program

Dogs ranged 5 to 9 years old (median age, 9.5 years), and included 5 castrated males, 2 intact females and 1 spayed female. There were 6 miniature dachshunds, 1 Shih-tzu and 1 Papillon. Median Hct and absolute reticulocyte count were 16.3% and 59,640/ll, respectively. Bone marrow erythroid series were evaluated as hyperplasia in 5 dogs, euplasia in 2 dogs and hypoplasia in 1 dog. Erythroid maturation arrest was observed in all dogs. 6 of 8 dogs underwent core biopsy and 2 dogs showed myelofibrosis. 5 of 8 dogs responded to the first regimen and time to response was between 28 and 52 days. 3 dogs stopped receiving the first regimen due to anorexia that might be induced by Cyclosporine. 6 month prognoses of the other 2 dogs were complete remission (CR: Hct increased to reference range) and partial remission (PR: Hct did not reach the reference range), respectively. 3 dogs that did not respond to first regimen were proceeded to the second regimen. 1 of 3 dogs showed response after 29 days and 6 month prognosis was PR. The other 3 dogs that discontinued receiving Cyclosporine were also proceeded to the second regimen, and 6 month prognoses were CR in 2 dogs and PR in 1 dog. 2 dogs that did not show any response to both treatments had myelofibrosis.