Investigating chronic, bright red, rectal bleeding

Chronic, bright red, rectal bleeding is a common symptom in our community and the aetiology is frequently benign anal disease. The aim of the present study was to determine the efficacy of performing a flexible sigmoidoscopy on patients with chronic, bright red, rectal bleeding who are at low risk for colorectal neoplasia and who, on rigid sigmoidoscopy, are found to have an identifiable anal cause (e.g. haemorrhoids, fissure) for their bleeding.

A prospective study was conducted on patients presenting with chronic, bright red, rectal bleeding. Patients were considered at low risk for colorectal neoplasia if they fulfilled the following criteria: (i) less than 55 years of age; (ii) no past or family history of colorectal neoplasia or inflammatory bowel disease; (iii) no symptoms of altered bowel habit or abdominal pain; and (iv) a source of bleeding identified (e.g. haemorrhoids, fissure) on rigid sigmoidoscopy. All patients underwent a flexible sigmoidoscopy.

Eighty-two patients were entered into the trial, mean age 39 +/- 9 years (range: 22-55 years), and the ratio of men:women was 1.8:1. The anal cause of bleeding was haemorrhoids in 96%, and anal fissure in 4%. At flexible sigmoidoscopy, five patients were found to have adenomatous polyps. Rigid sigmoidoscopy missed diminutive neoplastic lesions in 6% of patients.

Flexible sigmoidoscopy results in a low yield of colorectal neoplasia in patients presenting with chronic, bright red, rectal bleeding who are at low risk for colorectal neoplasia and who have an identifiable anal cause for their bleeding.