Clinical Course of Terminal Ileal Ulcers Observed Incidentally During Colonoscopy.

BACKGROUND: Cecal intubation is essential during colonoscopy, and observation of the terminal ileum is performed in most clinical practices. However, data on terminal ileal (TI) ulcers observed incidentally during colonoscopy are rare. AIM: We aimed to identify the characteristics and clinical course of TI ulcers observed incidentally during colonoscopy. METHODS: Between January 2008 and December 2018, medical records from multi-centers reporting asymptomatic subjects who underwent biopsy on TI ulcers during colonoscopy were retrospectively reviewed. The characteristics of endoscopic findings and clinical course of TI ulcers were analyzed, and the factors affecting the clinical course of TI ulcers were evaluated. RESULTS: The median follow-up durations from first to second colonoscopy and from second to third colonoscopy were 20 months (interquartile range, 12-36) and 24 months (interquartile range, 12-34), respectively. A total of 134 subjects were included in the analysis. The histopathologic findings of TI ulcers were mostly chronic or active ileitis/inflammation (92.7%). On the second colonoscopy, 59 (44.0%) patients had no ulcers, 38 (28.4%) showed a decrease in size or number, and 37 (27.6%) patients showed no change in ulcers. Among 62 subjects who underwent a third colonoscopy, 14 (10.4%) had decreased size or number, 10 (7.5%) had no ulcer change, and two (1.5%) had increased ulcer size or number. In multivariate logistic regression analysis, a star shape was the only factor affecting continuation without improvement of incidental TI ulcers. CONCLUSIONS: Most TI ulcers observed incidentally showed no unusual findings on biopsy and improved on follow-up colonoscopy without treatment.