Abstract:
Epstein - Barr Virus (EBV) is a member of the family of Human Herpes Viruses. It may be acquired and continue to be carried without expression of any clinical disease, or following a primary disease episode, most commonly infectious mononucleosis. In susceptible individuals it causes nasopharyngeal carcinoma, Burkitt and other lymphomata and oral hairy leukoplakia. Over 90% of the Kenyan population is seropositive for EBV, but immunocompetent individuals maintain the virus in a latent phase. In the course of HIV infection, changes in EBV activity are associated with the development of a variety of lymphoproliferative disorders. The aim of this study was to identify whether or not reactivation of EBV, and its attendant risks, can be detected in HIV positive patients, and whether such reactivation might have diagnostic or prognostic value in the management of the disease. A total of 101 adult subjects were randomly selected from HIV seropositive outpatients at Mbagathi District Hospital, Nairobi. Clinical and sociodemographic data were captured using a questionnaire, followed by a clinical examination of the head, neck and mouth. Citrated venous whole blood was used for EBV antibody assays by solid phase ELISA using EBV Profile 2 TM kits (Medizinische Labordiagnostika AG, Lubeck, Germany). The presence of anti EBNA-1, p22 and EA-D antibodies were regarded as diagnostic of reactivation disease, which is the stage at which AIDS lymphomas develop. The proportion of the study population who were positive for EBV antibodies was 95% while 5% were negative. Of those who were positive 18%, 60% and 11% were in early, late and reactivated infection respectively. EBV serostatus was then analyzed in relation to the subjects’ stage of HIV disease. The HIV clinical stage distribution of the study patients was Stage 1: 5.9% , Stage 2 : 35.6% and Stage 3 : 57.8% . The Odds Ratio for reactivated EBV infection with HIV Stage 3 as the exposure was 0.1 (95% CI 0.03 – 1.00). Thus, no significant risk of reactivation of EBV infection in HIV stage 3 was demonstrated. The Odds Ratio for advanced EBV disease (late and reactivated infection) with HIV stage 1 and 2 as the exposure was 0.32 (95% CI = 0.1 – 1.1). Cluster analysis of high intensity protein bands demonstrated EBNA1/EA-D as the weakest but most significantly different cluster pair in all HIV clinical stages. Whatever the stage of HIV disease or degree of overall immunosupression, reactivation of EBV has potentially serious neoplastic consequences for the patient. Although this study did not demonstrate a significant risk of Reactivation of EBV with HIV clinical stage 3 as the exposure factor, EBNA and EA-D appear to be the strongest candidate biomarkers of EBV reactivation in this population. Further research into biomarkers of EBV reactivation would result in diagnostic tests to help in early detection of EBV associated lymphomas in HIV patients.
