American Board of Internal Medicine (ABIM) Certification Practice Exam

How often should patients with ulcerative colitis undergo surveillance colonoscopy once screening begins?

1. Every year

2. Every 2-3 years

3. Every 1 to 2 years

4. Every 5 years

The correct answer is: Every 1 to 2 years

Patients with ulcerative colitis are at an increased risk for colorectal cancer, particularly if their disease has been present for more than eight years. Surveillance colonoscopy becomes critical as it enables early detection of dysplasia or cancer, which can significantly improve outcomes. The recommended interval for surveillance colonoscopy is typically every 1 to 2 years, starting eight years after the onset of symptoms or diagnosis of ulcerative colitis. This frequency allows for effective monitoring of any precancerous changes in the colon lining, helping to initiate timely intervention if necessary. In contrast, annual surveillance could lead to unnecessary procedures and increased healthcare costs without significantly improving patient outcomes. Every 2-3 years may not be frequent enough to catch dysplastic changes early. The recommendation for every 5 years is also too infrequent given the increased risk over time, particularly for patients with long-standing disease. This careful balance of frequency aims to maximize the chances of early intervention while minimizing risk and burden on the patient.