The outpatient evaluation of hematochezia

Abstract

Objective: The objective of this study was to determine whether specific clinical symptoms associated with hematochezia are predictive of important GI pathology and whether full colonoscopic examination is necessary. Methods: A total of 103 outpatients (≥ 45 yr) with hematochezia, defined as the passage of bright red blood per rectum, underwent anoscopy and colonoscopy. Before endoscopy, patients completed a detailed interview, quantitating the amount and frequency of bleeding, weight loss, use of aspirin/NSAIDs, change in bowel habits, family history, and prior GI illnesses. Based on this information, physicians were asked to predict whether the bleeding was from a perianal or more proximal site. At colonoscopy, pathology was stratified as either proximal or distal to the sigmoid/descending junction. Substantial pathology was defined as one or more adenomas > 8 mm, carcinoma, or colitis. Results: Anoscopy demonstrated internal and external hemorrhoids in 78 and 29 patients, respectively. On colonoscopy, 36 patients had 43 substantial lesions. Thirty-seven of these lesions were distal to the junction of the descending and sigmoid colons and six were proximal lesions. Four patients had cancer; all were distal lesions. Patients with substantial lesions were more likely to give a history of blood mixed within their stool ( p = 0.03), to have more episodes of hematochezia per month ( p = 0.008), and to have a significantly shorter duration of bleeding before medical evaluation ( p = 0.02) than did patients without such lesions. However, the physician's clinical assess- ment did not predict reliably which patients were likely to have substantial pathology. Conclusions: In patients with hematochezia, clinicians were unable to distinguish between those patients with and those without significant colonic lesions by history alone. Flexible sigmoidoscopy would have demonstrated most (95%) substantial lesions. The lesions that flexible sigmoidoscopy missed were an unlikely cause of bleeding in this small group of patients.