[Role of Colonoscopy in Patients with Hematochezia].

Background/aims: Although colonoscopy is not indicated in patients with hematochezia, many surgeons, internists, and physicians are recommending colonoscopy for these patients in Korea. The aim of this study is to evaluate the diagnostic value of colonoscopy for patients with hematochezia.

Methods: We retrospectively reviewed the data of colonoscopy between January 2010 and December 2010. A total of 321 patients among 3,038 colonoscopies (10.6%) underwent colonoscopy to evaluate the cause of hematochezia. The patients with previous colorectal surgery (2) or polypectomy (5) were excluded. We analyzed endoscopic diagnoses. Advanced neoplastic polyps were defined as adenomas with villous histology or high grade dysplasia, or adenomas more than 10 mm in diameter.

Results: Hemorrhoid was the most common diagnosis (217 cases, 67.6%). Polyps were detected in 93 patients (29.0%), but advanced neoplastic polyps were found in only 14 cases (4.4%). Colorectal cancers were diagnosed in 18 patients (5.6%) including 14 rectal cancers. There was no cancer located above sigmoid-descending junction. Diverticuli were detected in 41 patients (12.8%) but there was only one case of suspected diverticular bleeding. Colitis was diagnosed in 24 patients (7.5%). Other lesions included acute anal fissure, rectal tumor, stercoral ulcer, and radiation proctitis.

Conclusions: The colonoscopy had little value in patients with hematochezia because the most pathologic lesions were located below sigmoid colon. The first choice of diagnosis in patients with hematochezia is sigmoidoscopy.