RESUMEN
Anemia is the most frequent complication of chronic renal failure. Epoetin therapy reveals to be an effective therapy; however, development of anti-erythropoietin antibodies has been reported. The present study was conducted to determine the etiology of refractory anemia after Epoetin therapy in patients with chronic renal failure. All adult patients [530 patients] who had been prescribed regular hemodialysis and rHUEPO for at least three months were followed in seven hemodialysis units in Tehran. During a 6- month period, Venofer-Eprex dose and hemoglobin was recorded monthly. Having ruled out hemolysis and iron deficiently state in severe anemic patients, bone marrow examination was ordered. Of 530 patients, 58% were men with median age of 59 years. About%80 of patients had received baseline dose of at least 4000 units Eprex per week, prescribed subcutaneously after hemodialysis. Approximately, 21% were not anemic, while 19% did suffer from severe anemia [Hb<8]. There were statistically significant associations between severity of anemia and age [p<0.001], longer Epoetin therapy [p<0.001], co-treatment with Venofer [p<0.011] and lack of underlying disease [p<0.04]. Bone marrow aspiration was performed for 30 patients and the most frequent findings were anemia due to chronic disease, bone marrow dysplasia, amd megaloblastic anemia. In case of poor response to Epoetin therapy, discontinuing the drug is strongly recommended. Bone marrow examination is an appropriate tool to find the cause of refractoriness to Epoetin therapy in hemodialysis patients