Epstein-Barr Virus (EBV) is a ubiquitous Y-herpesvirus. EBV usually established a lifelong asymptomatic infec­tion in immunocompetent people. On the other hand, EBV can cause severe problems in immunocompromised patients. In recipients of allogeneic hematopoietic stem cell transplant (allo-HSCT), EBV infection may progress to the onset of a post-transplant lymphoproliferative disease (PTLD). EBV-PTLD is a life-threatening complication with a high mortality rate of 80-90 % and incidence between 0.5 – 1.3 %. In 71 paediatric allogeneic allo-HSCT re­cipients transplanted at Department of Paediatric Haematology and Oncology, Haematopoietic Stem Cell Trans­plantation Unit, Comenius University Children’s Hospital, Bratislava between 2013 and 2017, there were inves­tigated the impact of routine EBV DNA monitoring the incidence of EBV infection, the potential risk factors and the development of EBV-PTLD. Quantitative realtime PCR assay was performed on all blood samples for all pa­tients. High EBV DNAemia levels were observed in 57 % of the actively infected recipients (52 %). Matched-un­related donor transplant and CMV reactivation were associated with the high viral load. Two patients developed EBV PTLD. The key to the initiation of early treatment is regular EBV DNA PCR monitoring in correlation with clin­ical symptoms and presence of risk factors. Immunotherapeutic intervention includes reduction of immunosup­pression and administration of anti-CD20 monoclonal antibody (rituximab), adoptive immunotherapy with the administration of EBV-specific T-cells or donor lymphocyte infusion (DLI).

Keywords: Epstein-Barr Virus, post-transplant lymphoproliferative disease (PTLD), Hematopoietic Stem Cell Transplantation (HSCT), rituximab