Plasma Epstein-Barr viral load measurement as a diagnostic marker of lymphoma in HIV-infected patients.

BACKGROUND AND OBJECTIVES To assess the use of the Epstein-Barr virus (EBV) viral load as a marker for lymphoma diagnosis in HIV-infected patients. We also aimed to identify the relationship between EBV viral load in plasma and the presence of EBV in lymphoma cells. PATIENTS AND METHODS Retrospective observational study of two HIV-infected populations: one of patients diagnosed with lymphoma and a control group. Thirty-nine patients with AIDS-related lymphoma (ARL) (32 non-Hodgkin's and 7 Hodgkin's lymphomas) and 134 HIV-positive individuals without neoplasia or opportunistic infections were studied. Blood samples were collected before lymphoma treatment in ARL patients. EBV viral load was measured in plasma by real-time quantitative PCR and the presence of EBV-EBER mRNA in lymphoma tumor was investigated by in situ hybridization. RESULTS Patients with ARL had higher EBV viral loads than those without lymphoma: 24,180.5 (±73,387.6)copies/mL versus 2.6 (±21.6)copies/mL (p<0.001). HIV-infected patients without lymphoma had negative or very low EBV load values. Among ARL patients, no correlation was found between EBV viral loads and CD4+ lymphocyte counts or between EBV and HIV RNA loads, or any other clinical or biological parameter. Cases with an EBV-EBER-positive lymphoma had higher EBV viral loads than those with EBER-negative tumors. CONCLUSIONS EBV viral load is a useful marker of lymphoma in HIV-infected patients, and may be a useful tool for early diagnosis and treatment.