Consider colonoscopy for young patients with hematochezia

Results

Two hundred twenty-three patients younger than 50 years with rectal bleeding underwent complete colonoscopy to the cecum or terminal ileum. Of the 223 patients, 170 (76%) were evaluated at the University of Utah Medical Center, and 53 (24%) were evaluated at the VA Medical Center. No major complications (hemorrhage, perforation, hypoxia) directly related to endoscopy were noted.

The Table summarizes colonoscopy findings. Of the 223 patients, 48 (21.5%) had a normal outcome. Abnormalities were found in 175 patients (78.5%). Hemorrhoids were the most common finding, present in 135 patients (60.5%). In 98 patients (73%), hemorrhoids were the only finding, excluding non-adenomatous polyps. In the other patients with hemorrhoids, coincident adenomas, colitis, and diverticulosis were also diagnosed. Other anorectal diseases, including rectal ulcers or anal fissures, were found in 14 patients (6.3%).

Twenty-six patients (11.6%) had colon neoplasms, either adenomas or adenocarcinomas. Four patients (1.8%) had adenomatous polyps 8 mm in the distal colon. Eighteen patients (8.1%) had adenomas <8 mm; 6 (2.7%) had polyps only in the proximal colon. Hyperplastic polyps were not included in this analysis. Four patients (1.8%) had adenocarcinomas. These cancers were located in the rectum or sigmoid colon. The ages of these patients ranged from 32 to 48 years. One cancer patient had a distant cousin who died of colon cancer at the age of 47; no others had a family history of colon cancer.

Biopsy-proven chronic colitis was found in 13 patients (5.8%). Among the 7 patients who had colitis in the proximal colon, colitis was present in the distal colon as well. Angiodysplasia was found in 2 of the patients (0.9%) and only affected the distal colon. Diverticulosis was found in 19 patients (8.5%).

TABLE
Colonoscopy findings in 223 patients with rectal bleeding

Discussion

Rectal bleeding is a common problem in the US population. In a questionnaire sent by mail, 235 of 1643 respondents (15.5%) aged 20–64 years reported rectal bleeding. ²⁴ The prevalence was higher in younger persons: 18.9% for those aged 20–40 years vs 11.3% for those older than 40 years (P<.001). Only 13.9% of all patients with rectal bleeding in this study had visited a physician for bowel problems in the past year.

A major challenge for the clinician is deciding if a diagnostic endoscopy is necessary and, if so,whether flexible sigmoidoscopy or colonoscopyshould be done. Certainly, the concern of missinga potentially early and curable colon neoplasm substantiates the argument favoring colonoscopy. However, the costs, risks, and inconvenience of doing colonoscopy on every patient with rectal bleeding may overshadow the benefit.

Normal/benign findings

Either normal findings or benign diseases are commonly documented in younger patients with rectal bleeding. Approximately 21% of patients in this study had normal findings on colonoscopy. Hemorrhoids are believed to be the most common cause of rectal bleeding in all age groups, accounting for 27%–72% of cases.^8,19

In a random community sample of 202 people older than 30, with no history of cancer or inflammatory bowel disease, 16% reported rectal bleeding in the preceding 6 months. ²⁵ About 43% of the respondents believed they had “hemorrhoids,” based on the presence of anal pain, bleeding, protrusion, or perianal itching. In our study, about 60% of patients had documented hemorrhoids and 6.3% had other anorectal pathology, including anal fissures and rectal ulcers.

Colitis

Colitis was found in nearly 6% of our patients, which is similar to the incidence reported in series on older patients. ^26,26,26 Another study found that 6 of 102 patients under the age of 50 with rectal bleeding had colitis. ²⁸ All the patients with colitis in our series were found to have involvement of the distal colon.

Colorectal cancer

Several studies have evaluated the prevalence of colorectal cancer among patients with rectal bleeding. An overall incidence of 4%–19% is reported in some series that included patients older than 50 years. ^8,26

In a study of 280 patients younger than 40 by Acosta et al,¹¹ the incidence of colon cancer was 0.03%. Lewis et al retrospectively evaluated 570 patients younger than 50 years with rectal bleeding and found only 1 patient with colorectal cancer.²⁷ An additional 6.7% of patients had colorectal adenomas.

A limitation of this study, however, was that only 40% of patients had a colonoscopy; the other 60% had a flexible sigmoidoscopy. We found a colorectal cancer incidence of 1.8% among patients under 50 years old and all of these cancers were found in the distal colon.