Pure red cell aplasia following ABO-incompatible bone marrow transplantation: response to erythropoietin.

Allogeneic bone marrow transplants with major ABO incompatibility may be associated with delayed erythroid engraftment. A case of a male patient with erythroleukemia (blood group O) who received a bone marrow transplant from an HLA-identical sibling (blood group AB) is reported. The bone marrow transplantation was followed by normal myeloid and megakaryocytic engraftment, but pure red cell aplasia was present for more than 230 days after bone marrow transplant. Despite documentation of an elevated endogenous erythropoietin level (360 mU/mL; normal value, < 19 mU/mL) during the period of absent erythropoiesis, erythroid engraftment was observed soon after the initiation of human recombinant erythropoietin at a dose of 50 U per kg daily. This experience suggests that high-dose erythropoietin may stimulate sufficient production of erythroid precursors to overcome circulating inhibitors resulting in the correction of pure red cell aplasia.