Colonoscopy in the diagnosis of unexplained rectal bleeding

Abstract

Colonoscopy, done to elucidate the cause of obscure tectal bleeding not diagnosable on the basis of previous proctoscopic and Ba-enema examinations, resulted in a 17% diagnostic yield in this series. Of 105 patients 18 had lesions: 3 had carcinomas, 6 had polyps, 8 had colitis and 1 had proctitis. When bleeding was demonstrated by the physician, there was a higher diagnostic yield (22.5%) than when bleeding was reported only by the patient (5.9%). Descriptions of the bleeding by the patients were somewhat unreliable. Of the 18 lesions revealed by the colonoscope, 16 were in the left colon. The basic work-up for undiagnosed rectal bleeding should include history, physical examination, sigmoidoscopy and Ba-enema study. When no diagnosis is found, subsequent work-up must be individualized. When bleeding was demonstrated to originate from the colon, colonoscopic examination should be performed.