Prolonged red cell aplasia after major ABO-incompatible allogeneic hematopoietic stem cell transplantation: removal of persisting isohemagglutinins with Ig-Therasorb immunoadsorption.

Delayed donor red cell engraftment and prolonged red cell aplasia (PRCA) are well-recognized complications of major ABO-incompatible myeloablative and non-myeloablative hematopoietic stem cell transplantation (HSCT). There is an intense debate about the impact on outcome, severity of hemolysis, association with graft-versus-host disease and survival after blood group-incompatible stem cell transplantation. Therefore, therapeutic strategies should be considered to avoid these possible complications. We present five patients, who received allogeneic HSCT from human leukocyte antigen-identical donors for hematological malignancies, which were treated with Ig-Therasorb immunoadsorption (five treatments/week) to remove persisting incompatible isohemagglutinins. After a median of 17 treatments (range 9-25), all the patients became transfusion independent with the presentation of donor's blood group. No side effects occurred during treatment. Ig-Therasorb immunoadsorption seems to be a promising therapeutic method for rapid, efficient and safe elimination for persisting isohemagglutinins for patients with PRCA after allogeneic hematological stem cell transplantation.