A previously healthy 12-year-old boy presented with abdominal pain, vomiting, and abdominal distention of 3 days' duration. On physical examination, hyperpigmented macules were seen on his lips (Panel A). A computed tomographic scan showed proximal jejunojejunal (Panel B, arrow) and ileocolic intussusceptions. Surgical exploration revealed dilatation of the small bowel and necrosis of the jejunal intussusceptum. Resection of this segment and a short ileal intussusceptum containing a large polyp was performed, followed by primary anastomosis. Pathological evaluation showed multiple hamartomatous polyps in the necrotic jejunum and an ileal polyp 3.5 cm in diameter. The diagnosis was Peutz–Jeghers syndrome, an autosomal Join discussion...