Low incidence of HHV-6 reactivation in haploidentical hematopoietic stem cell transplantation with corticosteroid as graft-vs-host disease prophylaxis compared with cord blood transplantation.

Neither HLA disparity nor the use of methylprednisolone and antithymocyte globulin were risk factors for HHV-6 reactivation in our haplo-SCT patients. Rather than increasing risk, the administration of immunosuppressive agents potentially prevented HHV-6 reactivation after haplo-SCT by suppressing IL-6 production.