[Reduced-intensity umbilical cord blood transplantation for adult patients with fulminant aplastic anemia].

Allogeneic hematopoietic stem cell transplantation is recommended as a curative treatment option for fulminant aplastic anemia with no neutrophil despite the administration of granulocyte-colony stimulating factor. In the absence of an HLA-matched donor, unrelated cord blood transplantation (UCBT) is a treatment option that can be performed quickly. However, the optimal conditioning regimen of UCBT is yet to be established. We report two cases of fulminant aplastic anemia in adult patients who received UCBT. The first patient was a 52-year-old woman and the second was a 26-year-old man, both of whom received a conditioning regimen of total body irradiation (TBI; 2-4 Gy), fludarabine (Flu; 120 mg/kg), and cyclophosphamide (CY; 100 mg/kg) before UCBT. Short-term methotrexate and tacrolimus were used for prophylaxis of acute graft-versus-host disease (GVHD). Engraftments were achieved on days 26 and 19, and they exhibited complete donor chimerism by days 28 and 34. There was no evidence of acute GVHD, and therefore, the immunosuppressant drugs were discontinued. Reduced-intensity UCBT using a low-dose TBI/Flu/CY conditioning regimen could be an effective treatment option for fulminant aplastic anemia in the absence of a suitable donor.