title: [The risk factors of post-transplant lymphoproliferative disorders following haploidentical hematopoietic stem cell transplantation].
abstract: OBJECTIVE
  Post-transplant lymphoproliferative disorder (PTLD) occurring after allogeneic hematopoietic stem cell transplantation (allo-HSCT) is rare but severe. Risk factors including pre-HSCT exposure variables, conditioning regimens, transplant-related complications, and post-HSCT immune reconstitution were investigated in the development of PTLD after allo-HSCT.
  
  
  METHODS
  A nested case-controlled study was designed. Patients diagnosed with PTLD and controls match for time were identified from a cohort of 1 184 patients who underwent haploidentical HSCT between 2006 and 2012 for hematologic malignancies.
  
  
  RESULTS
  There were 12 PTLD patients with median time to diagnosis 63.5 d (45-360 d) post-HSCT. The pre-HSCT exposure variables, conditioning regimens and transplant-related complications of the two groups had no statistical difference. Similar rates of graft versus host disease (GVHD) and cytomegalovirus (CMV) infection were seen in both groups. But the absolute count of CD⁺₁₉ cells, CD⁺₃ cells, CD⁺₄ cells and CD⁺₈ cells at day 30 after HSCT, the serum IgG and IgM were much higher in the control group. In multivariate analysis, absolute count of CD⁺₄ cells lower than 0.019 9×10⁹/L (OR = 6.71, 95% CI 1.42-31.25, P = 0.016) at day 30 after HSCT was an independent risk factor for PTLD. Two cases (3.03%) of PTLD occurred in the low risk group (absolute count of CD⁺₄ cells ≥ 0.019 9 ×10⁹/L), the other 10 cases (15.15%) in the high risk group (absolute count of CD⁺₄ cells < 0.019 9 × 10⁹/L).
  
  
  CONCLUSIONS
  Patients with delayed immune reconstitution are at higher risk of developing PTLD after allo-HSCT. Improving the early immune reconstitution may help to decrease the incidence of PTLD after haploidentical HSCT.
authors.affiliation: Peking University People's Hospital, Peking University Institute of Hematology, Beijing 100044, China.
authors.forename: Chunli
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Peking University People's Hospital, Peking University Institute of Hematology, Beijing 100044, China.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Huang
authors.affiliation: Peking University People's Hospital, Peking University Institute of Hematology, Beijing 100044, China.
authors.forename: Daihong
authors.initials: D
authors.lastname: Liu
authors.affiliation: Peking University People's Hospital, Peking University Institute of Hematology, Beijing 100044, China.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Mo
authors.affiliation: Peking University People's Hospital, Peking University Institute of Hematology, Beijing 100044, China.
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Peking University People's Hospital, Peking University Institute of Hematology, Beijing 100044, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Chen
authors.affiliation: Peking University People's Hospital, Peking University Institute of Hematology, Beijing 100044, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Han
authors.affiliation: Peking University People's Hospital, Peking University Institute of Hematology, Beijing 100044, China.
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Peking University People's Hospital, Peking University Institute of Hematology, Beijing 100044, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Peking University People's Hospital, Peking University Institute of Hematology, Beijing 100044, China.
authors.forename: Jingzhi
authors.initials: J
authors.lastname: Wang
authors.affiliation: Peking University People's Hospital, Peking University Institute of Hematology, Beijing 100044, China.
authors.forename: Fengrong
authors.initials: F
authors.lastname: Wang
authors.affiliation: Peking University People's Hospital, Peking University Institute of Hematology, Beijing 100044, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Zhao
authors.affiliation: Peking University People's Hospital, Peking University Institute of Hematology, Beijing 100044, China.
authors.forename: Yanrong
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Peking University People's Hospital, Peking University Institute of Hematology, Beijing 100044, China.
authors.forename: Kaiyan
authors.initials: K
authors.lastname: Liu
authors.affiliation: Peking University People's Hospital, Peking University Institute of Hematology, Beijing 100044, China. Email: lpxu_0415@sina.com.
authors.forename: Lanping
authors.initials: L
authors.lastname: Xu
mesh_terms: D016022:Case-Control Studies; D003586:Cytomegalovirus Infections; D020031:Epstein-Barr Virus Infections; D006086:Graft vs Host Disease; D019337:Hematologic Neoplasms; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D015994:Incidence; D008223:Lymphoma; D008232:Lymphoproliferative Disorders / Q000453:epidemiology*; D012307:Risk Factors; D014184:Transplantation, Homologous