Which combination of conditions is listed under the mechanical or structural causes of chronic diarrhea?

• A. Chronic foreign body, chronic intussusception, short bowel syndrome
• B. Neoplasia and infection
• C. Toxins and medications
• D. Hypoperfusion

Answer: (A)

Mechanical or structural causes of chronic diarrhea come from physical changes in the gut that alter flow or absorption. A chronic foreign body can cause ongoing partial obstruction and irritation, leading to malabsorption and loose stools. Chronic intussusception creates intermittent obstruction, reducing contact time for digestion and absorption. Short bowel syndrome leaves a smaller absorptive surface, speeding transit and producing malabsorption with chronic diarrhea. Other categories involve non-structural processes like inflammation or secretory/osmotic mechanisms, such as neoplasia or infection, toxins and medications, or problems from reduced blood flow. So the combination of chronic foreign body, chronic intussusception, and short bowel syndrome fits under mechanical or structural causes.