Anemia of chronic renal failure in dogs

Seventeen dogs with chronic renal failure (CRF) were studied to evaluate the incidence, type, and etiology of anemia in CRF. A nonregenerative, normochromic, normocytic anemia was seen in 12 of 17 dogs (70.6%). There was a direct correlation between the degree of anemia and the extent of CRF as assessed by serum creatinine concentrations (P = .0386, r = .50923). Erythrocyte concentrations of 2,3-diphosphoglycerate (DPG) were significantly increased in anemic animals and showed a close correlation to the degree of anemia. The high DPG concentrations may compensate for the anemia by decreasing the hemoglobin-oxygen affinity and thereby facilitating tissue oxygenation at low hematocrits. Serum concentrations of erythropoietin (Epo) were in the low to normal range, despite mild to moderate anemia, documenting a deficiency of Epo in dogs with CRF. The nonregenerative nature of the anemia supports impaired hematopoiesis as a significant etiologic factor. Other factors, such as increases in serum parathyroid hormone and phosphorus, were not found to correlate significantly with the degree of anemia, although there were significant differences between their concentrations in anemic compared with non-anemic dogs. There was no change in erythrocyte osmotic fragility with uremia. The documentation of a nonregenerative, normochromic, normocytic anemia, with failure of an appropriate increase in Epo production, supports the therapeutic use of Epo in the management of the anemia seen in CRF in the dog.