title: Clinical Significance of Isolated Peri-Appendiceal Lesions in Patients With Left Sided Ulcerative Colitis.
abstract: BACKGROUND
  Ulcerative colitis is classically described as a condition originating in the rectum and extending proximally towards the cecum. In recent years, a discontinuous peri-appendiceal lesion has been described. Our aim was to evaluate the risk of progression to pancolitis in patients presenting with an isolated peri-appendiceal lesion on ileocolonoscopy.
  
  
  METHODS
  Endoscopy databases at three tertiary care centers were searched for patients undergoing ileocolonoscopy for diagnosis or surveillance of ulcerative colitis. Patients with isolated periappendiceal lesions as well as histologically confirmed left sided colitis were enrolled. Controls were defined as patients with left-sided ulcerative colitis without evidence of peri-appendiceal inflammation. The main outcome was the need for escalation of therapy to systemic corticosteroids, immunomodulators or biologic agents. Secondary outcomes were progression to pancolitis or requirement for colectomy. A secondary analysis of other risk factors for proximal extension/progression of colitis was also performed.
  
  
  RESULTS
  We identified 228 patients with ulcerative colitis, 123 were included in the analysis. Four point eight percent of patients had isolated peri-appendiceal lesions. In the group with peri-appendiceal lesions, 47.4% required escalation of therapy vs. 70% in the control group (P = 0.53). There was no difference in progression to pan-colitis or colectomy rates between the two groups. Progression was not predicted by inflammatory markers, age, gender, initial Mayo UC score or IBD therapy utilization.
  
  
  CONCLUSIONS
  The presence of isolated peri-appendiceal lesions is not a risk factor for future escalation of therapy for ulcerative colitis and is not correlated with proximal extension of disease.
authors.affiliation: University of Minnesota, Deparment of Internal Medicine, Division of Gastroenterology, MMC 36, 420 Delaware Street SE, Minneapolis, MN 55455, USA.
authors.forename: Yan
authors.initials: Y
authors.lastname: Bakman
authors.affiliation: University Hospitals Case Medical Center, Division of Gastroenterology, 11100 Euclid Avenue Cleveland, Ohio 44106-5066, USA.
authors.forename: Jeffry
authors.initials: J
authors.lastname: Katz
authors.affiliation: Regions Hospital, Digestive Care Center, 435 Phalen Blvd, Saint Paul, MN 55130, USA.
authors.forename: Chris
authors.initials: C
authors.lastname: Shepela
keywords: Cecal patch; Inflammatory bowel disease; Peri-appendiceal lesion; Ulcerative colitis; Ulcerative colitis therapy