Oral Presentation
<Lower GI 08>
Appendiceal Orifice Inflammation May Precede Development
of UC: Analysis of 20 Patients
Sang Hyoung Park1, Suk-Kyun Yang1, Mi-Jung Kim2, Dong-Hoon Yang1, Kee Wook Jung1,
Kyung Jo Kim1, Byong Duk Ye1, Jeong-Sik Byeon1, Seung-Jae Myung1 and Jin-Ho Kim1
Departments of 1Gastroenterology and 2Pathology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
Background & Study Aims: Appendiceal orifice inflammation (AOI) is considered as a distinct skip lesion of ulcerative colitis
(UC). In previous studies on AOI as a skip lesion of UC, the AOI was found together with the main UC lesion. However, it does
not necessarily mean that AOI develops concomitant with the main UC lesion. Therefore, we performed this study to investigate
the possibility of AOI as a preceding lesion in the development of UC.
Patients and Methods: A total of 20 patients with UC-like inflammatory lesions at the appendiceal orifice, without concomitant
typical features of UC, such as diffuse rectal involvement, were identified at the Asan Medical Center between January 2001
and December 2009. The subsequent clinical courses and endoscopic findings of all patients were analyzed.
Results: A total of 20 patients (mean age 41.2 years; 11 males) met our inclusion criteria. Nineteen patients were followed up
endoscopically for a mean duration of 18.4 months (range, 2-84 months). Typical UC (proctitis in four patients, extensive colitis in
one patient) developed in five patients (25%) in a mean time of 18.4 months (range, 2-36 months). Negative conversion of all
inflammatory lesions occurred in seven patients (35%) after a mean follow-up time of 20 months (range, 3-84 months). In the
remaining seven patients (35%), the initial lesions did not progress to UC and did not go into remission during the mean follow-up
time of 16.9 months (range, 2-42 months).
Conclusions: Our results suggest that, at least in some occasions, AOI precedes development of UC, and indicate that the appendix
may play a role in the pathogenesis of UC.
Key Words: Appendix; Inflammation; Ulcerative colitis
Clin Endosc Vol. 44 Suppl 1, 2011
S173