The role of colonoscopy in the evaluation of blood loss per rectum has
been studied extensively in older patients but not in the younger adu
lt population. The objective of this study was to review the diagnosti
c yield of colonoscopy in patients 40 years of age or younger with pas
sage of minimal amounts of bright red blood per rectum or occult blood
positive stools. Retrospectively, 5924 colonoscopic examinations were
reviewed. All patients, 40 years of age or younger, with rectal bleed
ing as the only indication for colonoscopy were selected. A total of 2
80 patients met these criteria and 59 (21%) had significant findings.
Polyps were present in 25 (8.9%) of patients. Other findings included
colitis, diverticular disease, and angiodysplastic lesions present in
8.6 per cent, 2.1 per cent, and 1.1 per cent, respectively. Adenocarci
noma was present in one patient (0.03%). These results suggest that co
lonoscopy in patients 40 years of age or younger with rectal bleeding
may be justified because significant findings may be present in up to
21 per cent of patients.