Sigmoid intussusception from submucosal lipoma in an adolescent

Colo-colic intussusception secondary to a submucosal lipoma is exceedingly rare, particularly in adolescents, and presents significant diagnostic and management challenges. A 16-year-old male presented with a 5-day history of left lower quadrant pain, nausea, vomiting, and currant jelly stool. Abdominal ultrasound identified a left iliac fossa mass, and contrast-enhanced computed tomography confirmed a submucosal lipoma with a 10 cm colo-colic intussusception and pelvic free fluid. Conservative management via contrast enema and sigmoidoscopy failed due to mucosal oedema and ulceration, and open sigmoid colectomy was performed. Histopathology confirmed a 32 mm mature lipoma as the lead point with no evidence of malignancy. The patient recovered well and was discharged on postoperative day ten. This case highlights that colo-colic intussusception in adolescents should not be presumed idiopathic. A pathological lead point must always be excluded, and when conservative measures fail, timely surgical resection ensures definitive treatment and favourable outcomes.