[Treatment of Gaucher disease with allogeneic hematopoietic stem cell transplantation: report of three cases and review of literatures].

OBJECTIVE To explore the efficacy of unrelated umbilical cord blood transplantation (UCBT) in the treatment of Gaucher disease. METHOD The clinical characteristics of three children with Gaucher disease underwent UCBT in our hospital between April 2013 and September 2014 were retrospectively analyzed. Literature on allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the treatment of Gaucher disease was searched at Wanfang and Pubmed databases between 1983 and 2015 and was reviewed and summaried. RESULT Three children with Gaucher disease, all were female, received UCBT. These patients' age at receiving transplantation was 3.8 years, 7.1 years and 2.6 years, respectively. The second case received the second transplantation. The first and third case received splenectomy before UCBT. The pretreatment regimen was busulfan (Bu)/fludarabine (Flu)/cyclophosphamide (CTX)/antithymocyte globulin (ATG), and for the patient received the second transplantation melphalan was added to the myeloablative conditioning regimen of Bu/Flu/CTX/ATG. Cyclosporine and mycophenolate mofetil (MMF) wee used for prophylaxis of acute graft versus host disease (aGVHD). The dose of cord blood stem cell nucleated cell counts was 9.7 × 10⁷ /kg,11.9 × 10⁷ /kg and 7.6 × 10⁷/kg respectively. The dose of cord blood stem cell CD34⁺ cell counts was 5.4 × 10⁵/kg , 3.5 × 10⁵/kg and 3.2 × 10⁵/kg respectively. The day of granulocytes exceeding 0.5 × 10⁹/L was day 11, 12 and 19 after transplantation, respectively. The day of platelets exceeding 20 × 10⁹/L was day 14, 33 and 74 after transplantation, respectively. At one month after transplantation the rate of chimerism was over 95% and all patients got donor complete chimerism. The level of β-glucocerebrosidase recovered to normal at one month after transplantation. During transplantation, all patients developed cytomegalovirus (CMV) and Epstein-Barr virus (EBV) viremia. In case 1 immune thrombocytopenia occurred at five month after transplantation unresponding to steroids and mesenchymal stem cells infusion was administered and his platelet in routine blood test recovered to normal. But the patient died because she was infected with varicella-zoster virus out of hospital at nine month after transplantation and the level of β-glucocerebrosidase was normal before death and chronic GVHD (cGVHD) was not found. The case 2 is now in 19th month after transplantation and his level of β-glucocerebrosidase was normal. cGVHD was not found. The patient is currently free of disease. The case 3 was in 9th month after transplantation and his level of β-glucocerebrosidase was normal. cGVHD was found at 112 day after transplantation and was localized and could be controlled by hormonal therapy. The patient is currently free of disease. Three patients' size of liver was significantly reduced after their level of β-glucocerebrosidase ecovered. There were 50 cases with Gaucher disease who were treated with allo-HSCT in the literature and none of them were reported from China. Disease-free survival rate of patients treated with allo-HSCT for Gaucher disease was 85%. In all reports, there were 31 cases who had information of typing of Gaucher disease, of whom 22 cases had type 1 and 9 cases had type 3. Twenty-nine cases had information of survival, of whom 24 cases survived and 5 cases died of infection. Fifteen cases had data of engraftment, 2 of whom had graft failure and one had late graft failure.Glucocerebrosidase recovered to normal in 25 of 31 cases who had relevant data, in one of whom with late graft failure the enzyme recovered to normal 3 month after transplantation, but his enzyme decreased to the initial level 9 month after transplantation. Along with enzyme level's recovery to normal, in a part of cases bone pain and hepatomegaly were relieved and growth delay was improved. CONCLUSION The unrelated UCBT may be a form of treatment that offers the potential of permanent cure and a procedure with possible long-term benefits in patients with Gaucher disease.