The (re)challenging question of erythropoiesis-stimulating agents inducing pure red cell aplasia

The introduction of recombinant human erythropoietin (EPO) into routine clinical practice in the late 1980s heralded a new dawn for the treatment of anaemia in chronic kidney disease (CKD). Apart from the financial burden, limiting its use in the developing world, the early sideeffect profile was mild. It has been shown that full correction of anaemia, requiring high doses of EPO, does not confer mortality benefit to patients suffering from CKD [1,2], and is potentially detrimental to survival [1] even in haemodialysis patientswith cardiac disease; the administration ofEPOto raise haematocrit to42 is not recommended [3]. Pure red cell aplasia (PRCA), secondary to EPO, will form the basis of this review. This idiosyncratic immunological reaction involves the generation of anti-EPO antibodies (Abs) resulting in significant anaemia. The mechanisms governing this immunological response remain only partially understood. Whilst PRCA is infrequent, the disease is severe, and the aggressive treatment requirements present a significant complication to patients and a therapeutic conundrum to the treating clinician.