Ileal duplication mimicking intestinal intussusception: a congenital condition rarely reported in adult.

Intestinal duplication is an uncommon congenital condition in young adults. A 25-year-old man complained of chronic, intermittent abdominal pain for 3 years following previous appendectomy for the treatment of suspected appendicitis. Abdominal discomfort and pain, suggestive of intestinal obstruction, recurred after operation. A tubular mass was palpable in the right lower quadrant. Computed tomography enterography scan identified suspicious intestinal intussusception, while Tc-99m pertechnetate scintigraphy revealed a cluster of strip-like abnormal radioactivity in the right lower quadrant. On exploratory laparotomy, a tubular-shaped ileal duplication cyst was found arising from the mesenteric margin of the native ileal segment located 15 cm proximal to the ileocecal valve. Ileectomy was performed along with the removal of the duplication disease, and the end-to-end anastomosis was done to restore the gastrointestinal tract continuity. Pathological examination showed ileal duplication with ectopic gastric mucosa. The patient experienced an eventless postoperative recovery and remained asymptomatic within 2 years of postoperative follow-up.