American Board of Internal Medicine (ABIM) Certification Practice Exam

What symptom is commonly reported in patients with irritable bowel syndrome and usually does not necessitate colonoscopy?

1. Persistent vomiting

2. Passage of mucus

3. Bloody diarrhea

4. Weight loss

The correct answer is: Passage of mucus

Patients with irritable bowel syndrome (IBS) commonly report the passage of mucus in their stools. This symptom is typically associated with the gastrointestinal distress that characterizes IBS, which may manifest as changes in bowel habits, including diarrhea and constipation. The presence of mucus can be a frequent occurrence in IBS due to alterations in bowel function and gut motility. In contrast, other symptoms such as persistent vomiting, bloody diarrhea, and unexplained weight loss are more concerning for underlying pathologies that could require further investigation with colonoscopy. These symptoms may signal more serious conditions, such as inflammatory bowel disease, gastrointestinal infections, or malignancies, making them indicators for performing diagnostic procedures to rule out these possibilities. Since the passage of mucus is generally benign in the context of IBS and does not bear the same risk of alarming associated conditions, it does not typically necessitate a colonoscopy for evaluation.