Objective: Ischemic colitis (IC) spans a broad spectrum from self- limiting illness to intestinal gangrene and mortality. Prognostic factors specifically for nonpostoperative IC were not fully characterized. We aim to focus on nonpostoperative IC in patients with renal dysfunction and try to identify prognostic factors for adverse outcomes. Methods: We conducted a retrospective analysis at a university-affiliated tertiary medical center in Taiwan. From January 2003 to August 2008, 25 men and 52 women (mean age: 66 y) had colonoscopic biopsy-proven IC without prior culprit surgery. We estimated glomerular filtration rate with simplified Modification of Diet in Renal Disease equation. Nine patients with glomerular filtration rate below 30 mL per minute per 1.73 m(2) were classified as renal dysfunction group (including 7 dialysis patients). Adverse outcomes were defined as need for surgery and mortality. Predictors for adverse outcomes were captured by univariate and multivariate analysis. Research ethical committee approved the study protocol. Results: Patients with renal dysfunction more often had: diabetes mellitus (56 % vs. 16%, P = 0.02), prolonged symptoms (6.8 d vs. 3.5 d, P = 0.01), lower hemoglobin (11.1 g/dL vs. 13.4 g/dL, P = 0. 01), and more often right colonic involvement (56% vs. 19%, P = 0.03). Renal dysfunction patients also had longer hospitalization days (median 15 d vs. 4 d, P = 0.045). However, there was no statistical significance in the rate of either surgery or mortality between these 2 groups (P > 0 .05). Univariate analysis showed that renal dysfunction, sex , emergency department referral, presentation with abdominal pain were significant for adverse outcome (P