Incidental EBV-positivity in paediatric post-transplant specimens demonstrates the need for stringent criteria for diagnosing post-transplant lymphoproliferative disorders

Aims To examine the need for minimal diagnostic criteria for post-transplant lymphoproliferative disorders (PTLD) in children, we sought to determine the rate of incidental Epstein-Barr virus (EBV)-positivity in tissues from organ transplant recipients (OTR). Methods EBV in situ hybridisation (ISH) was done retrospectively on tissue from 34 paediatric autopsies of OTR and paediatric tonsillectomy specimens from non-OTR (96) and OTR (6). Patients with a history of PTLD were excluded from both data sets. Results EBV-positivity was found incidentally in 2/34 autopsy cases (5.9%). Median time from transplant to death for all patients was 12.8 months (range 0.1-153 months). Median time between transplant and death in EBV-positive cases was 34 months. EBV was positive in 26/102 tonsils (25%). Among tonsils from OTR, 4/6 (67%) were EBV-positive. Conclusions These findings reinforce the need for strict morphological and clinical criteria, other than EBV-positivity, when diagnosing PTLD in the paediatric population.