P295. Atypical distribution of inflammatory lesions in ulcerative colitis: is it really rare?
S.H. Park1, S.-K. Yang1, S.-K. Park1, J.W. Kim1, D.-H. Yang1, K.W. Jung1, K.-J. Kim1, B.D. Ye1, J.-S. Byeon1, S.-J. Myung1, J.-H. Kim1, 1University of Ulsan College of Medicine, Asan Medical Center, Gastroenterology, Seoul, South Korea
Although continuous inflammation in the colon is a hallmark of Ulcerative colitis (UC), several studies have reported the frequent observation of endoscopic “skip” lesions in the colon including appendix. But the clinical implication of this finding is unclear. Therefore, the aim of this study was to evaluate the endoscopic findings and patterns of distribution of lesions in patients with newly diagnosed, untreated UC.
We retrospectively analyzed colonoscopic findings and clinical courses of 240 patients with UC first diagnosed at the Asan Medical Center between January 2001 and December 2009.
Of the 240 included patients, 194 patients (80.8%) showed typical distribution of lesions and 46 patients (19.2%) showed atypical distribution of lesions such as segmental, patchy inflammatory lesions except appendiceal orifice inflammation (AOI). They were detected more frequently in the proximal portions of colon than in the distal portions of colon (p 0.001). Of eight patients who had segmental-colitis type of UC (i.e. without rectal involvement), six patients developed typical rectal inflammatory lesions on follow-up colonoscopy.
Endoscopic “skip” lesions in proximal parts of the colon may not be a rare finding in patients with initial, active UC. Clinicians need to be aware that skip lesions in addition to AOI may occur in untreated patients with UC for appropriate diagnosis and management.