[Pure red cell aplasia in erythropoietin therapy in patients with kidney failure]

Since the nineties of the previous century, incidence of pure red-cell aplasia (PRCA) in patients with chronic renal failure (CRF) and renal anaemia treated with recombinant human erythropoietin (rHuEPO) has significantly increased. Due to the positive effects of rHuEPO on quality of life, lowering of morbidity and mortality of patients with CRF, such increased incidence has attained a widespread interest, though PRCA remains only a rare complication. The responsibility for the development of PRCA lies with the neutralizing anti-erythropoietin antibodies. The rise of antibodies and development of PRCA is related to the subcutaneous administration of erythropoietin and in the vast majority of patients to the treatment with Eprex, one of the epoetins alpha. At present, the most probable explanation is a change of the stabilizer in Eprex formulation, which is related to the increased immunogeneity of the product. The subcutaneous administration of rHuEPO, preferred for medical and economical reasons in both American and European guidelines, is known for its higher immunization power. Properties of the product, emphasized by the route of administration, can cause the rise of these antibodies. To prevent the rise of anti-erythropoietin antibodies and the development of PRCA, regulatory authorities and Eprex producers decided that Eprex cannot be administered to CRF patients subcutaneously, but only intravenously. Also the requirements on the handling of Eprex have become more stringent. Limitations do not concern either epoetin beta (NeoRecormon) or other epoetins alpha (of which the latter are not available in this country). Therapy of PRCA in patients treated with rHuEPO is based on suspension of rHuEPO and on the immunosuppressive therapy. Many questions concerning PRCA in CRF patients treated with rHuEPO remain unsolved. It is necessary to study further the ethiopathogenesis of this complication and possibly adjust preventive and therapeutic measures.