Which of the following is NOT a listed cause of GI obstruction?

• A. Infection
• B. Adhesions
• C. Hernias
• D. Ulcers

Answer: (A)

GI obstruction refers to a blockage in the intestinal lumen, so the main focus is distinguishing mechanical blockage from a functional slowdown of motility. The usual mechanical causes are adhesions from prior surgeries that kink or compress bowel and hernias that trap a loop of intestine. Ulcers can contribute to obstruction only in specific, uncommon scenarios like gastric outlet obstruction due to scarring, but they aren’t a primary cause of mechanical intestinal obstruction. Infection, however, doesn’t create a true lumen blockage; it often leads to a paralytic ileus—a diffuse slowing of motility rather than a physical obstruction. So infection isn’t a listed mechanical cause of GI obstruction, which is why it’s the correct answer.