P227 Evaluation of a method to detect cytomegalovirus-DNA in intestinal fluid samples of patients with ulcerative colitis

Abstract

Background: A severe flare and refractory against steroid in patients with ulcerative colitis (UC) may be complicated by underlying cytomegalovirus (CMV) infection. Pathological detection of the cells infected by CMV in colonic mucosal biopsies is golden standard in diagnosis, however; pathological diagnosis has certain false negative cases. Although CMV antigenemia and polymerase chain reaction (PCR) for detecting CMV in mucosal samples have been widely applied, PCR for CMV in intestinal fluids has not been evaluated. The aim of the study was to investigate the usefulness of PCR for CMV in intestinal fluids of patients with UC. Methods: From 2012 to 2013, 36 patients (16 men, 20 women) with UC were enrolled in this study. Intestinal fluid samples and biopsies were collected during colonoscopy. We evaluated clinical characteristics, CMV antigenemia, real-time PCR for CMV in intestinal fluids and colonic mucosal biopsies, and histopathological examination of colonic mucosal biopsies. Results: Twenty-three of 53 intestinal fluid samples (43%) had detectable CMV DNA, and five of 28 colonic mucosal samples (18%) were positive for CMV DNA. In both examinations, the positive rates of CMV DNA were higher in patients with colonic deep ulcer than in patients without deep ulcer. All 5 cases with positive CMV DNA in mucosal biopsies had all detectable CMV DNA in intestinal fluids, whereas 8 cases with detectable CMV DNA in intestinal fluid samples had negative CMV DNA in mucosal biopsies. In these 8 cases, 7 cases were refractory to steroid, and two patients underwent colectomy. The average of amount of CMV DNA in intestinal fluid samples positive/ mucosal biopsies negative case was 14.3 copies, whereas the other average which is both positive case was 56.9 copies. Conclusions: PCR for detecting CMV in intestinal fluids is useful and easy for diagnosis of CMV infection in patients with UC. This method has a higher sensitivity compared with mucosal biopsies. Most cases of negative results in pathology and detected by intestinal fluids were refractory cases to steroid. This method enables prompt and appropriate treatment.