Clinical Significance of Surveillance Pouchoscopy in Asymptomatic Ileal Pouch Patients with Underlying Inflammatory Bowel

Abstract

Purpose: 1) To evaluate the frequency of dysplasia detected in asymptomatic patients undergoing surveillance pouchoscopy; 2) To investigate the frequency and risk factors of various pouch disorders incidentally found on the surveillance pouchoscopy. Methods: This cross-sectional study included all consecutive patients referred for surveillance pouchoscopy in our subspecialty Pouchitis Clinic from 2002-2011. Symptomatic patients undergoing diagnostic pouchoscopy and pouch patients with underlying familial adenomatous polyposis were excluded. Univariable and multivariable analyses. Results: A total of 138 patients met the inclusion criteria and were included, with 72 (52.2%) being male. The mean age at the time of ileal pouch construction was 45.4±15.0 years, with the mean interval from stoma closure to the inception surveillance pouchoscopy of 89.4 ± 78.8 months. We found 1 patient with indefinite dysplasia on pouch mucosal biopsy (0.7%) and 2 patients with non-caseating granulomas, suggesting Crohn's disease (CD) of the pouch. Of all patients, 69 (50.0%) had abnormal endoscopic findings, 102 (73.9%) had abnormal histopathological changes (including acute and chronic inflammation, pyloric gland metaplasia), and 64 (46.4%) had both during the surveillance pouchoscopy. The abnormal endoscopic findings included pouch ulcer (n=29, 21.0 %), pouchitis (n=31, 22.5%), inflammatory polyps (n=10; 7.2%), and pouch strictures at the anastomosis (n=5, 3.6%)), pouch inlet (n=10; 7.2 %), pouch outlet (n=2, 1.4%). Thirteen patients with pouch strictures underwent endoscopic balloon dilatation and nine patients had endoscopic polypectomy. Compared with patients who had normal endoscopic findings, patients with abnormal endoscopy were more likely to have a preoperative diagnosis of CD (p=0.026) and have concomitant extraintestinal manifestations (EIM, p=0.011). However, no significant difference was identified between the two groups in other 21 demographic and clinical variables. Multivariable analysis showed that patients with a preoperative diagnosis of CD and concomitant EIM had a high risk for have abnormal pouch endoscopic findings with odds ratios of 2.552 (95% confidence interval [CI]: 1.108˜16.545, p=0.035) and 4.281 (CI: 1.204˜5.409, p=0.014) respectively. Conclusion: Dysplasia or cancer appeared to be rare in asymptomatic patients with IPAA who underwent the one-time pouchoscopy. However, approximately ½ of the patients had “incidental” abnormal findings on pouchoscopy and some of them had clinically-indicated endoscopic therapeutic intervention. Therefore, the surveillance pouchoscopy may deliver the benefits of diagnostic and therapeutic maneuvers in other pouch disorders, particularly for those with a preoperative diagnosis of CD or EIM.Table: Multivariate analysis of risk factors associated with abnormal endoscopic findings in asymptomatic patients with ileal pouches