Transfusion-related Epstein-Barr virus infection among stem cell transplant recipients: a retrospective cohort study in children.

BACKGROUND Blood safety warrants strict screening measures to minimize the risk of transmitting blood-borne pathogens. However, transfusion-transmitted infections for which testing is not currently performed continue to be a concern. Among these untested agents is Epstein-Barr virus (EBV) which, in the transplant setting, is associated with lymphoproliferative disease, a potentially fatal cancer. The aim of this study was to analyze the incidence of posttransplant EBV infection and its association with administration of blood products in children receiving a hematopoietic stem cell (HSC) graft. STUDY DESIGN AND METHODS This retrospective cohort study sought to review charts of pediatric recipients of HSC grafts to collect information on the presence of EBV antibodies in the recipients' pretransplant sera and in HSC donor sera, incidence of posttransplant EBV infection, and patients' transfusion history. Cumulative incidence of posttransplant EBV infection was estimated by Kaplan-Meier methods according to pretransplant serology. The association between blood products and EBV infection was measured by Cox regression models. RESULTS The pretransplant EBV seroprevalence was 77.9% for recipients and 61.8% for graft donors. Virtually, all recipients received blood products during the peritransplant period. Among seronegative recipients, the 30- and 60-day cumulative incidences of posttransplant EBV infection were 4.6 (95% confidence interval [CI], 1.2-17.3) and 13.4% (95% CI, 5.8%-29.4%), respectively. The 60-day cumulative incidence was 8.3% (95% CI, 2.2%-29.4%) when restricting the analysis to seronegative recipients of cord blood grafts. Importantly, there was a clear positive trend associating EBV infection to transfusion volume. CONCLUSION This study suggests an association between transfusions and posttransplant EBV infection in HSC transplant recipients.