Detection of Epstein-Barr virus DNA in plasma reliably signaled “a broad range” of EBV+ diseases, according to investigators.

In contrast, the presence of EBV DNA in peripheral blood mononuclear cells did not reliably predict EBV diseases, said Dr. Jennifer A. Kanakry and her associates at Johns Hopkins University, Baltimore. Patients without EBV diseases can have EBV DNA in their PBMCs, particularly if they are immunocompromised, the researchers observed.

Latent EBV infection is associated with lymphomas, lymphoproliferative disorders, hemophagocytic lymphohistiocytosis, solid tumors, and other diseases. To characterize the relationship between these diseases and EBV DNA, the researchers studied viral quantitative real-time polymerase chain reaction assays of plasma and PBMCs from 2,146 patients tested at Johns Hopkins over 5 years. Patients were usually immunocompromised and hospitalized, the investigators noted ( Blood 2016;127:2007-17 ).

A total of 535 patients (25%) had EBV detected in plasma or PBMCs. Notably, 69% of patients who did not have EBV diseases had EBV in PBMCs, but not in plasma. Among 105 patients with active systemic EBV+ diseases, 99% had EBV DNA in plasma, but only 54% had EBV in PBMCs. Furthermore, the number of copies of EBV DNA distinguished untreated EBV+ lymphoma, remitted EBV+ lymphoma, and EBV- lymphoma, and also distinguished untreated, EBV+ post-transplantation lymphoproliferative disorder (PTLD), EBV+ PTLD in remission, and EBV– PTLD.

“Cell-free (plasma) EBV DNA performs better than cellular EBV DNA as a marker of a broad range of EBV+ diseases,” the investigators concluded. “Within a largely immunocompromised and hospitalized cohort, detection of EBV DNA in plasma is uncommon in the absence of EBV+ disease.”

The National Cancer Institute, National Institutes of Health, and Center for AIDS Research funded the study. The researchers had no disclosures.