'One-stop' rectal bleeding clinics without routine flexible sigmoidoscopy are unsafe.

Over 90% of patients referred to surgeons for investigation of rectal bleeding have haemorrhoids, fissure-in-ano or proctitis. Full investigation of these patients to exclude colonic neoplasia or inflammatory bowel disease imposes a considerable load on a hospital's resources as well as exposing the patient to significant inconvenience and morbidity. A 'one-stop' outpatient clinic was established, with selective use of flexible sigmoidoscopy, based on the judgement and clinical findings of a single experienced surgeon. Over a 4 month period, 344 patients were assessed, and 326 were identified as not needing flexible sigmoidoscopy. At 3 and 6 monthly follow-up, 22 presented with persistent rectal bleeding and three previously unidentified cancers were found on performance of flexible sigmoidoscopy. If a 'one-stop' policy is to be used in the management of rectal bleeding, routine flexible sigmoidoscopy is essential for all patients.