ESA-induced pure red cell aplasia presenting as a precipitous hemoglobin drop in end-stage renal disease

Abstract

Anemia is a nearly universal complication of chronic kidney disease (CKD). While erythropoiesis-stimulating agents (ESAs) are the standard of care, they rarely induce acquired pure red cell aplasia (PRCA) via neutralizing anti-erythropoietin (anti-EPO) antibodies. Diagnosis is often delayed as clinical focus frequently shifts toward more common causes of acute anemia, such as hemorrhage. An 88-year-old male on maintenance hemodialysis presented with a precipitous hemoglobin drop to 6.8 g/dL. Investigation revealed replete hematinics but profound reticulocytopenia. After excluding occult gastrointestinal bleeding, hemolysis, and nutritional deficiencies, a bone marrow biopsy demonstrated isolated erythroid aplasia with preserved myeloid and megakaryocytic lineages, leading to a diagnosis of PRCA. Anti-EPO antibody testing was not performed, which limits definitive etiological confirmation. Due to the high risk of immunosuppression in an elderly patient and the limited accessibility of hypoxia-inducible factor-prolyl hydroxylase inhibitors (HIF-PHIs), management was restricted to ESA cessation and supportive transfusions. This case highlights the diagnostic approach for severe anemia and the significance of profound reticulocytopenia in PRCA. The definitive hallmark remains the detection of circulating anti-EPO antibodies paired with a bone marrow study demonstrating near-total depletion of erythroid precursors, but preserved myeloid and megakaryocyte lineages. Management includes the permanent cessation of ESAs, immunosuppression to reduce circulating antibodies, and supportive blood transfusions. In chronic hemodialysis patients, early recognition of iatrogenic PRCA is essential to prevent the continued administration of potentially harmful ESAs and to facilitate a transition toward alternative therapies, such as HIF-PHIs.