Failure to detect Epstein-Barr virus (EBV) DNA in plasma by real-time PCR in a case of EBV-associated posttransplantation lymphoproliferative disorder confined to the central nervous system.

We report here a patient who developed multiple central nervous system (CNS) space-occupying lesions 6 months after bone marrow transplantation from an HLA-matched unrelated donor. He had extensive chronic graft-versus-host disease and severe thrombocytopenia. Posttransplantation lymphoproliferative disorder (PTLD) was diagnosed after biopsy of the lesion was facilitated by the transfusion of 40 units of platelets. Epstein-Barr virus (EBV) DNA was not initially detected in the peripheral blood by real-time polymerase chain reaction, and the blood became positive for EBV at a low level only after more than 6 weeks had passed since the initial identification of detectable intracranial lesions. The patient died of cerebral herniation while donor leukocyte infusion was being prepared, and an autopsy confirmed the diagnosis of EBV-associated PTLD restricted to the CNS.