Efficacy and long-term outcome of treatment for pure red cell aplasia after allogeneic stem cell transplantation from major ABO-incompatible donors.

No standard of care for pure red cell aplasia (PRCA) after major ABO-incompatible hematopoietic stem cell transplantation (HSCT) has been established. We conducted a retrospective cohort study to learn the efficacy and outcome of treatment for PRCA. One hundred forty-five recipients who showed delayed recovery of erythropoiesis and survived >100 days after transplantation without early disease progression were selected from 2846 records of major ABO-incompatible transplantation in the registry database in Japan, and detailed data of 46 recipients were collected. Treatment of PRCA, such as rapid tapering of calcineurin inhibitors, corticosteroids, or additional immunosuppressants, was given to 22 patients but not to the other 24 patients. The overall response rate of the treatment group was 54.5%. The number of days from diagnosis of PRCA to recovery of reticulocytes >1% and the cumulative number of red blood cell transfusions were not significantly different between the 2 groups. Infections accounted for the death of 7 of 11 patients in the treatment group. Univariate analysis identified 5 variables influencing survival, including graft-versus-host disease, disease progression, and treatment of PRCA; disease progression remained as the only factor negatively affecting survival by multivariate analysis. The present study could not provide supportive evidence for the beneficial effects of treatment for PRCA after major ABO-mismatched HSCT.