Efficacy of Darbepoetin alfa in anemic dogs with Chronic Kidney Disease – a review of 21 cases

Anemia due to Chronic Kidney Disease (CKD) represents a major portion of hemodynamic imbalance in dogs. Although the pathogenesis of the anemia in CKD is multifactorial, decreased production of erythropoietin by the diseased kidneys has been proven and the severity of anemia correlates positively with serum creatinine concentrations in affected dogs. Therapeutic whole and Packed Red Blood Cell transfusion has always been a main stay in practice. However, the unavailability of appropriate dog donors, blood typing modalities and occurrence of post transfusion reactions are the common hurdles encountered. Alternatively, Darbepoetin alfa, a hyperglycosylated synthetic recombinant erythropoietin which is commonly used in human patients with CKD induced anemia is used in recent canine practice. Unlike human transfusion medicine, not much of study has been documented in dogs in India. However anecdotally, darbepoetin is perceived to less likely form antibodies compared to erythropoietin. A study comprising of 21 dogs referred to Madras Veterinary College Teaching Hospital (MVCTH) with CKD (stage II, III & IV were 7, 9 & 5 respectively) of multifactorial etiology during the period of January to December 2017 was done. Injectable Darbepoetin was administered @0.5μg/kg subcutaneously once in a week for three weeks along with supplementation of Iron to achieve a medium hematocrit of 30%. Efficacy of Darbepoetin was evaluated by measuring pre and post therapeutic clinico pathological studies. Darbepoetin proved effective in increasing PCV, anemic crisis potentially in 66.7% of dogs. Hypertension, vomiting, melena, inappetance were common findings in affected dogs and coexistence of normocytic, normochromic progressive anemia which responds to Darbepoetin alfa therapy. Though expensive than Erythropoietin, Darbepoetin @0.5μg/kg s/c proved safe and effective in improving packed cell volume in CKD dogs as an alternative to packed RBC or whole blood transfusion. Further immunological, toxicological and clinical studies on Darbepoetin therapy is warranted in a large population in dogs. Keywords: Ckd; Azotemia; Anemia; Darbepoetin