title: Appendiceal orifice inflammation as a skip lesion in ulcerative colitis: an analysis in relation to medical therapy and disease extent.
abstract: BACKGROUND
  Although several reports have claimed that the appendix can be involved as a skip lesion in ulcerative colitis, they do not exclude the possibility that this skip lesion occurs as a result of medical therapy. Also, little is known about the relation between the presence of appendiceal orifice inflammation and the extent of the disease.
  
  
  METHODS
  The presence of appendiceal orifice inflammation was prospectively assessed both endoscopically and histologically in 94 patients with active ulcerative colitis, the extent of whose disease had not been beyond the hepatic flexure. To evaluate the effect of prior medical therapy on the prevalence of appendiceal orifice inflammation, all cases were divided into two groups. Group A consisted of 66 patients who had been treated before inclusion; group B was composed of 28 patients newly diagnosed at inclusion.
  
  
  RESULTS
  Appendiceal orifice inflammation was diagnosed in 24 (26%) of 94 patients with active subtotal ulcerative colitis, with no statistical difference observed between group A (23%) and group B (32%). In all 94 patients, the frequency of appendiceal orifice inflammation decreased significantly as the extent of disease increased, i.e., 37% in proctitis (n = 49), 17% in left-sided colitis (n = 36), and 0% in extensive colitis (n = 9) (p < 0.05).
  
  
  CONCLUSIONS
  Appendiceal orifice inflammation as a skip lesion of ulcerative colitis is not rare, is more frequently observed in patients with less extensive disease, and is not the result of patchy improvement due to medical therapy.
authors.affiliation: Departments of Internal Medicine and Diagnostic Pathology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: S K
authors.initials: SK
authors.lastname: Yang
authors.forename: H Y
authors.initials: HY
authors.lastname: Jung
authors.forename: G H
authors.initials: GH
authors.lastname: Kang
authors.forename: Y M
authors.initials: YM
authors.lastname: Kim
authors.forename: S J
authors.initials: SJ
authors.lastname: Myung
authors.forename: K N
authors.initials: KN
authors.lastname: Shim
authors.forename: W S
authors.initials: WS
authors.lastname: Hong
authors.forename: Y I
authors.initials: YI
authors.lastname: Min
mesh_terms: D000328:Adult; D001064:Appendicitis / Q000453:epidemiology / Q000209:etiology / Q000473:pathology*; D001707:Biopsy, Needle; D016009:Chi-Square Distribution; D003093:Colitis, Ulcerative / Q000150:complications / Q000473:pathology* / Q000628:therapy; D003113:Colonoscopy; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D012984:Software