Carbamazepine-induced pure red cell aplasia in an elderly patient with ESKD on hemodialysis: a case report

Pure red cell aplasia (PRCA) is a rare blood disorder characterized by the selective absence of erythroblasts in an otherwise normal bone marrow, leading to severe reticulocytopenic anemia. In patients with end-stage kidney disease (ESKD) undergoing hemodialysis, PRCA is most often caused by anti-erythropoietin (EPO) antibodies induced by recombinant human EPO therapy. However, non-EPO-stimulating agent (ESA) drugs can also trigger PRCA, although this is underrecognized in this patient population. Carbamazepine, a widely used anticonvulsant, has rarely been implicated in PRCA, with only a few cases reported in the general population and none in patients undergoing dialysis. Herein we describe a case of carbamazepine-induced PRCA in an elderly male patient with ESKD undergoing hemodialysis, whose anemia improved after carbamazepine discontinuation. A 70-year-old male patient with ESKD undergoing hemodialysis for eight years presented with sudden-onset of severe anemia, with a hemoglobin (Hb) of 6.2 g/dL. This marked a sharp decline from his usual Hb level ranged of 10.0–11.0 g/dL while being intravenously administered an ESA (epoetin-α, three times a week). Bone marrow examination confirmed a diagnosis of PRCA. Further examination identified carbamazepine-induced PRCA as the likely cause. The results of the enzyme-linked immunoassay, used to test for anti-EPO antibodies, were also negative. Carbamazepine was discontinued and replaced with levetiracetam (Keppra®) for an anticonvulsant effect. One month later, the patient’s Hb level increased to 8.7 g/dL and red blood cell (RBC) transfusions were no longer required. However, two months later, his Hb level again decreased to 7.3 g/dL. These findings suggest that the patient’s anemia was caused by EPO deficiency due to chronic renal failure. This condition was treated by gradually increasing the ESA dose, which ensured that the patient’s Hb level remained stable at 11.0 g/dL. This is the first reported case of carbamazepine-induced PRCA in a patient undergoing hemodialysis that resolved with drug withdrawal alone, thereby avoiding the need for immunosuppressive therapy.