Endoscopy for hematochezia in patients under 50 years of age.

The optimal strategy for evaluating rectal bleeding in young persons is unknown. This study examines the prevalence of adenomatous neoplasms identified at endoscopy for rectal bleeding. Retrospective cross-sectional analysis was made of patients under 50 years of age undergoing elective outpatient colonoscopy or flexible sigmoidoscopy for hematochezia. In all, 570 patients (309 F/261 M) met our inclusion criteria. The prevalence of neoplasms was 3.8% (95% CI 1.2-8.5%) among persons under 30, 2.8% (95% CI 0.9-6.3%) among persons age 30-39, and 10.9% (95% CI 7.4-15.4%) among persons age 40-49. The prevalence of neoplasms was higher in persons over age 40 (relative risk 3.43, 95% CI 1.70-6.94). Six of seven advanced neoplasms were identified in persons over age 40 (relative risk 7.4, 95% CI 0.89-60.7). In conclusion, the prevalence of colonic neoplasms in patients 40-50 years old with hematochezia is substantial. Among those persons younger than 40 years, the prevalence of colonic neoplasms is significantly lower.