Right colonic involvement is associated with severe forms of ischemic colitis and occurs frequently in patients with chronic renal failure requiring hemodialysis.

OBJECTIVE: The aim of this study was to identify factors associated with severe outcome in patients with ischemic colitis.
METHODS: The files of 60 consecutive inpatients (34 women, 26 men, mean age 67 yr) with ischemic colitis were reviewed. The following data were analyzed: age, sex, smoking, medications, history of cardiovascular disease, metabolic disease, chronic renal failure and hemodialysis, the time elapsed between the first symptoms and the diagnosis, and the site and extension of their colonic involvement. Patients were divided into two groups according to outcome: those with severe disease, including those who died from ischemic colitis (n = 3) or who required surgical resection (n = 21); and those with mild forms of colitis who were treated successfully without surgery (n = 36). The two groups were compared by means of univariate and multivariate analysis to identify factors associated with unfavorable outcomes. Only patients who had a complete examination of the colon (n = 51) were entered into the statistical analysis.
RESULTS: By univariate analysis, chronic renal failure (p = 0.03), hemodialysis (p = 0.01), short delay between symptoms and diagnosis (p = 0.01), and right colonic involvement (p = 0.002) were significantly more common in the patients with severe colitis. By logistic regression, right colonic involvement was the only factor independently associated with severity (p = 0.01). Right-sided lesions were present in 82% of patients on dialysis but in only 26% of patients not on dialysis (p = 0.0005).
CONCLUSIONS: Right colonic involvement is associated with severe forms of ischemic colitis and occurs frequently in patients with chronic renal failure requiring hemodialysis.