The Status of Epstein-Barr Virus Infection in Intestinal Mucosa of Chinese Patients with Inflammatory Bowel Disease.

AIMS: This cross-sectional study is to investigate the presence of Epstein-Barr virus (EBV) in colonic mucosa of inflammatory bowel disease (IBD) patients and its correlation with the clinical disease activities and therapeutic regimens.

METHODS: Subjects undergoing colonoscopy for screening of polyps were recruited as control. EBV DNA load was analyzed by means of quantitative real-time polymerase chain reaction and EBV-encoded RNAs were tested by in situ hybridization in intestinal mucosa of IBD patients. EBV infection was defined as positive with either method. Clinical disease activity was assessed using the Mayo Clinic Score for ulcerative colitis and Crohn's disease activity index for CD.

RESULTS: EBV was detectable in 33 out of 99 IBD patients (33.3%). In controls, EBV prevalence was 7.5% (3/40). We found a significant correlation between EBV prevalence and clinical disease activities (mild [10.71%, 3/28] versus moderate [32.73%, 18/55], severe [75.00%, n = 12/16], p < 0.001). However, no significant difference was found in EBV prevalence between patients who received immunosuppressive therapy and those who did not.

CONCLUSIONS: EBV infection is common in colonic mucosa of IBD patients. There is a significant correlation between EBV infection and clinical disease activities of IBD. However, prospective studies are still needed to explore the exact role of EBV in IBD.