Pure Red Cell Aplasia Induced by Antibodies against Human Recombinant Erythropoietin

Human recombinant erythropoietin (epoetin) is a very effective and safe biopharmaceutical. However, in 1998 the incidence of pure red cell aplasia (PRCA) induced by antierythropoietin (anti-EPO) antibodies in patients treated with epoetin started to increase. PRCA is a rare condition of non-regenerative anemia which can be associated with a variety of diseases and is in some cases of immunological origin. To date the incidence rate of epoetininduced PRCA has fallen again. The temporary rise in incidence was associated with the subcutaneous use of the epoetin alpha preparation distributed outside the USA and followed a change in the formulation of this product to human serum albumin-free polysorbate 80. Among several reasons that have been explored, the most likely cause has been the contamination of the solution with organic compounds leaching from rubber stoppers of pre-filled syringes. The diagnosis of PRCA is based on typical clinical features, detection of anti-EPO antibodies and typical findings in bone marrow. In cases of suspected PRCA, epoetin medication needs to be discontinued immediately. Immunosuppressive treatment can be successful and should be initiated if possible once the diagnosis has been confirmed.