A 55-year-old woman who underwent truncal vagotomy with antrectomy and Billroth II reconstruction one year ago now develops tremulousness, sweating, palpitations and difficulty concentrating about two to three hours after each meal. Symptoms resolve promptly with glucose intake. What is the underlying mechanism?

• A Hyperosmolar chyme drawing fluid into the gut lumen causing hypovolaemia
• B Exaggerated insulin response causing reactive hypoglycaemia ✓
• C Vagal denervation causing gastric stasis and fermentation
• D Afferent loop obstruction with bacterial overgrowth

Explanation

Late dumping occurs two to three hours after meals when rapid delivery of carbohydrate into the small intestine provokes an exaggerated insulin surge, producing reactive hypoglycaemia with adrenergic and neuroglycopenic symptoms relieved by glucose. Early dumping, by contrast, occurs within 30 minutes due to hyperosmolar contents shifting fluid into the intestinal lumen, causing vasomotor and gastrointestinal symptoms. Treatment of late dumping centres on small, frequent, low-carbohydrate meals; octreotide is used in refractory cases.

Reference: Schwartz's Principles of Surgery, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.