[Haploidentical hematopoietic stem cell transplantation for the treatment of severe aplastic anemia in children].

This study was purposed to assess the effectiveness of haploidentical hematopoietic stem cell transplantation (HSCT) without in vitro T cell depletion for the treatment of severe aplastic anemia (SAA) in children. Two children with SAA/very SAA (VSAA) received T cell-depleted HSCT from their fathers with 2 loci mismatched in our center between October 2010 and March 2013. During 4 months after onset, both failed in treatment of cyclosporine (CsA)+ granulocyte colony stimulating factor (G-CSF), had active or serious infections, were transfusion dependent and lacked HLA-identical sibling donors and unrelated donors. The conditioning regimen before HSCT included fludarabine, cyclophosphamide and thymoglobulin. The source of grafts was a combination of G-CSF mobilized peripheral blood hematopoietic stem cells and BM. The recipients received CsA, mycophenolate mofetil (MMF) and short-term MTX for GVHD prophylaxis. Both children with SAA achieved 100% donor myeloid engraftment. Neutrophil engraftment occurred at day 12 and day 18 after transplant respectively. Platelet engraftment occurred at day 17 and day 26 after transplantation respectively. Two patients all developed grade I acute graft versus host disease (GVHD), one of which evolved into chronic limited GVHD well-controlled. Both have survived for two years after transplantation with 100% donor myeloid engraftment and effective lymphoid reconstitution. In conclusion, these limited cases suggest that haploidentical HSCT for children with SAA without a HLA-identical sibling donor and unrelated donor may be feasible. Further prospective clinical study is required to increase the overall survival (OS) by decreasing GVHD while maintaining stable engraftment.