Steatorrhea is most characteristic of which type of diarrhea?

• A. Small bowel
• B. Large bowel
• C. Both
• D. Neither

Answer: (A)

Steatorrhea reflects fat malabsorption, which is a hallmark of diarrhea arising from the small intestine. For fats to be absorbed, bile acids and pancreatic lipase must act in the small bowel; when this process is disrupted—due to mucosal disease, bile acid issues, or pancreatic insufficiency—fat stays in the lumen and is excreted in the stool as bulky, greasy, pale, foul-smelling stools that may float. In contrast, diarrhea originating in the large intestine tends to be more liquid or watery without excess fat content, often with increased frequency but not fatty stools. So the presence of steatorrhea points to a small-bowel type of diarrhea.