[The clinical characteristics of adult hemophagocytic lymphohistiocytosis treated with haploidentical donor hematopoietic stem cell transplantation].

Objective: To analyze the clinical characteristics of adult patients with hemophagocytic lymphohistiocytosis (HLH) receiving haploidentical donor hematopoietic stem cell transplantation (HID HSCT). Method: We retrospectively reviewed 20 adult patients with HLH from August 2009 to August 2014.The clinical features and outcome were analyzed. Results: Conditioning regimens consisted of total body irradiation/etoposide/cyclophosphamide (TBI/VP-16/CTX) and busulfan (Bu)/VP-16/CTX in HLH with anti-thymocyte globulin (ATG) 8 mg/kg.The stem cells were mobilized from donors' peripheral blood.Median time to white blood cell engraftment was 13 (9-27) days.Median time to platelet engraftment was 14 (10-28) days.Mixed chimerism after transplantation developed in 4 patients and no patient presented graft failure.Eight patients developed grade Ⅱ to Ⅲ acute graft-versus-host disease (GVHD), while as chronic GVHD occurred in 9 patients.Among 12 patients with EB virus(EBV) reactivation, 2 patients developed post-transplant lymphoproliferative disorder (PTLD), 7 were suspected as PTLD and 3 were considered as relapse of primary disease.With a median follow-up of 20 months (range: 0.5-108 months) after transplantation, the estimated 2-year overall survival (OS) rate was (60.0±11.0)% in all patients.During the follow-up, 12 patients survived, 8 died including 5 within 100 days after HSCT.Among 5 non-remission patients before HSCT, 4 patients died within 100 days after HCT. Conclusions: HID HSCT is an effective treatment for adult patients with HLH to achieve remission and long-term survival. High proportion of mixed chimerism has been seen at early stage after transplantation.EBV reactivation and early transplant-related mortality are common.