title: Risk factors for post-transplant lymphoproliferative disorder in pediatric patients: a case-control study.
abstract: Post-transplant Lymphoproliferative Disorder (PTLD) because of the Epstein-Barr Virus (EBV) is a major concern after pediatric transplantation. The group at greatest risk is EBV-seronegative recipients who receive EBV-seropositive organs. Additional risk factors remain to be determined, including those among EBV-seropositive recipients. In this case-control study, PTLD cases were biopsy-proven over a period of 4 yr (1997-2000, inclusive). Each case was matched with 2 controls, based on the type of organ transplanted and the period of transplantation (+/-1 yr). Variables compared between cases and controls included those relating to the clinical and virologic profiles and immunosuppressive therapy. Twenty-two cases of PTLD were diagnosed during the study period. PTLD cases occurred at a median of 22.8 months post-transplantation (range 1-131). The median age of cases was 26.2 months (range 6.1-194) compared with 47.4 months (range 0.8-202.2) for controls (p = 0.93). Cases had a higher mean baseline EBV load compared with controls (3.1 log(10) (s.d. +/- 1.0) vs. 1.6 log(10)/10(6) PBMCs (s.d. +/- 1.4), with every 1 log increase in viral load resulting in a three times increase in the likelihood of PTLD (p < 0.007). Close to one in four cases of PTLD were EBV-seropositive pretransplantation. These seropositive recipients tended to be older patients with a trend to a worse outcome compared with their seronegative counterparts. The occurrence of PTLD was not associated with the use of any specific immunosuppressants. A significant proportion of PTLD cases occurred among EBV-seropositive transplant recipients, with a tendency towards an unfavorable outcome. Besides EBV-seronegative recipients who receive seropositive organs, some EBV-seropositive pediatric patients are at risk of PTLD. Additional studies are warranted to further define the factors associated with PTLD in EBV-seropositive transplant recipients.
authors.affiliation: Division of Infectious Diseases, The Department of Pediatrics, Hospital for Sick Children, University of Toronto, Ontario, Canada. upton.allen@sickkids.ca
authors.forename: Upton D
authors.initials: UD
authors.lastname: Allen
authors.forename: Gabrielle
authors.initials: G
authors.lastname: Farkas
authors.forename: Diane
authors.initials: D
authors.lastname: Hébert
authors.forename: Sheila
authors.initials: S
authors.lastname: Weitzman
authors.forename: Derek
authors.initials: D
authors.lastname: Stephens
authors.forename: Martin
authors.initials: M
authors.lastname: Petric
authors.forename: Raymond
authors.initials: R
authors.lastname: Tellier
authors.forename: Bo
authors.initials: B
authors.lastname: Ngan
authors.forename: Annie
authors.initials: A
authors.lastname: Fecteau
authors.forename: Lori
authors.initials: L
authors.lastname: West
authors.forename: Samia
authors.initials: S
authors.lastname: Wasfy
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D020031:Epstein-Barr Virus Infections / Q000150:complications*; D005260:Female; D004854:Herpesvirus 4, Human / Q000276:immunology*; D006801:Humans; D007223:Infant; D016015:Logistic Models; D008232:Lymphoproliferative Disorders / Q000821:virology*; D008297:Male; D016377:Organ Transplantation; D012307:Risk Factors