A patient who underwent truncal vagotomy with gastrojejunostomy two years ago now reports chronic troublesome diarrhoea unrelated to meals. Which mechanism best explains post-vagotomy diarrhoea?
- A Loss of receptive relaxation causing rapid gastric emptying of hyperosmolar contents
- B Bacterial overgrowth from loss of acid barrier in the stomach
- C Denervation of the biliary tree and small intestine causing disordered motility and bile salt malabsorption ✓
- D Excess gastrin secretion from retained antrum
Correct answer: C. Denervation of the biliary tree and small intestine causing disordered motility and bile salt malabsorption
Explanation
Truncal vagotomy divides vagal fibres to the entire abdominal viscera, including the biliary tract and small intestine. Denervation produces disordered intestinal transit, rapid bile acid delivery to the colon and bile salt induced secretory diarrhoea, typically watery and unrelated to meals. Rapid emptying of hyperosmolar contents explains early dumping rather than chronic diarrhoea, and bacterial overgrowth contributes less commonly. Highly selective vagotomy avoids this complication by sparing the nerves of Latarjet.
Reference: Bailey and Love's Short Practice of Surgery, 28th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.