Prevalence of Cytomegalovirus and Epstein Barr Virus in Inflamed Colon Tissue of Patients with Mild to Moderate Inflammatory Bowel Disease – Preliminary Results

Abstract

Purpose: Cytomegalovirus (CMV) infection and Epstein Barr virus (EBV) DNA have been detected in colon tissue of patients with severe steroid refractory inflammatory bowel disease (IBD). However, the prevalence of CMV and EBV infection in colon tissue from patients with less severe IBD is not known. We aimed to evaluate the prevalence of CMV and EBV infection in colon tissue of patients with mild to moderate IBD as compared to their prevalence in normal colon mucosa of non IBD patients, non inflamed colon mucosa in same IBD patients and inflamed mucosa in patients with other inflammatory diseases of the colon. Methods: Consecutive colonic tissue biopsy specimens were taken through colonoscopy from 41 patients with quiescent and mild to moderate IBD (N = 30 with ulcerative colitis and N = 11 with Crohn's colitis) and from 49 control patients; N = 6 with colitis from other inflammatory conditions of the colon and N = 43 from patients without IBD undergoing colonoscopy for purposes of colorectal cancer screening. Detection of CMV and EBV infection from tissue biopsies was performed using quantitative PCR and immunohistochemistry or in-situ hybridization. Results: Prevalence of CMV and EBV in inflamed mucosa of quiescent and mild-moderate IBD is 8.1% and 11.4%, respectively. CMV was significantly more prevalent in inflamed mucosa of UC patients compared to healthy controls (11.5% vs 0%; P < 0.05). EBV is significantly more prevalent in inflamed mucosa of IBD and ulcerative colitis patients as compared to healthy controls (11.4% vs 0%; P < 0.04, 11.5% vs 0%; P < 0.05 respectively). CMV and EBV were not detected in non inflamed mucosa of IBD patients and EBV was detected in inflamed mucosa of one patient (16.7%) with other inflammatory conditions of the colon. When compared with inflamed mucosa of IBD patients, the differences were not statistical significant. Conclusion: CMVand/or EBV have a predilection for inflamed mucosa in IBD patients. Whether the presence of CMV and/or EBV in inflamed mucosa predispose IBD patients to the development of severe steroid refractory disease remains to be determined.