The value of prospective monitoring of Epstein-Barr virus DNA in blood samples of pediatric liver transplant recipients.

Post-transplant lymphoproliferative disease (PTLD) is one of the major causes of morbidity and mortality in transplantation patients. A primary Epstein-Barr virus (EBV) infection is a major risk factor for developing PTLD. The aim of this study was to determine circulating EBV DNA after liver transplantation in pediatric patients in relation to primary EBV infection and development of PTLD. EBV serology was performed before transplantation. Every 4 weeks after transplantation a competitive quantitative polymerase chain reaction (PCR) assay for EBV nuclear antigen-1 was performed in 13 patients. Patients were followed for development of a PTLD. Before transplantation four patients were EBV seropositive and nine patients were EBV seronegative. In one of the four patients who were EBV seropositive before transplantation, EBV DNA became detectable after transplantation, with a peak load of 3600 copies/mL. None of these four patients developed a PTLD. Eight of the nine patients who were EBV seronegative before transplantation developed positive EBV DNA samples. EBV DNA was first detected at a mean of 64 days after transplantation (range 38-89). The mean peak EBV DNA load was 79,700 copies/mL (3600-446,000). Two of these patients developed PTLD, but they could not be identified based on prior or concomitant EBV PCR results.In pediatric liver transplantation EBV DNA load is higher in patients with a primary infection than in patients who were EBV seropositive before transplantation. The EBV PCR cannot be used to identify individual patients who develop PTLD. However, elevated EBV DNA load can be used to detect a group of patients at increased risk for PTLD.