Sirolimus-based immunosuppression as GVHD prophylaxis after bone marrow transplantation for severe aplastic anaemia: a case report and review of the literature.

Congenital or acquired severe aplastic anaemia (SAA) is cured by bone marrow transplantation (BMT) from a histocompatible leukocyte antigen- (HLA-) identical sibling. The best conditioning regimen is cyclophosphamide (CTX) with or without antithymocyte globulin (ATG), followed by short-term methotrexate (MTX) and cyclosporine A (CsA) to prevent graft-versus-host disease (GvHD). In our pediatric oncology-hematology unit, a 5-year-old girl with SAA was treated with two BMT from the same HLA-identical sibling donor. Severe CsA-induced adverse events (severe hypertension and PRES) after the first BMT led necessarily to CSA withdrawal. Alternative immunosuppressive treatment for GvHD prevention as tacrolimus and mycophenolate were not tolerated by our patient because toxicity > grade II. For this reason we decided to administrate sirolimus alone as GvHD prophylaxis and to prevent disease relapse after the rescue BMT. Here we report the successful use of sirolimus alone for GvHD prophylaxis after the second transplant in a pediatric BMT setting for SAA.