In the differential diagnoses for chronic small intestinal diarrhea, which option represents the pancreas-related extra-GI cause?

• A. Hypoperfusion
• B. Exocrine pancreatic insufficiency (EPI), chronic pancreatitis
• C. Toxins, medication side effects
• D. Chronic inflammatory enteropathy

Answer: (B)

The main idea is that pancreas-related extra-GI causes of chronic small intestinal diarrhea come from inadequate pancreatic enzyme secretion, which leads to maldigestion and steatorrhea. When exocrine pancreatic function is lost or severely diminished—as in chronic pancreatitis—the small intestine doesn’t receive enough lipase, amylase, and proteases (and bicarbonate) to properly digest fats and other nutrients. Fat isn’t absorbed well, so it stays in the lumen, draws water, and produces bulky, greasy, foul stools that persist as chronic diarrhea. This is why exocrine pancreatic insufficiency fits as a pancreas-related extra-GI cause. By contrast, hypoperfusion affects gut function through reduced blood flow rather than enzyme supply; toxins or medication side effects can cause diarrhea through varied mechanisms but don’t specifically implicate pancreatic digestion; chronic inflammatory enteropathy is a primary intestinal mucosal disease rather than a pancreatic deficit.