Adult ileocolic intussusception caused by a terminal ileal lipoma: A case report

Adult intussusception is a rare clinical condition. Unlike in pediatric cases, adult intussusception often has a definable lead point, with benign or malignant tumors being the most common etiology. Small intestinal lipoma is a rare cause of adult intussusception. It typically presents with non-specific symptoms and an insidious onset, frequently leading to misdiagnosis or discovery only during emergency surgery. Abdominal computed tomography (CT) plays a pivotal role in preoperative diagnosis, yet its specific findings in lipoma-induced intussusception warrant further emphasis.

A 30-year-old man presented with a one-week history of abdominal pain and distension, followed by dark red bloody stools for four days. Physical examination revealed abdominal distension and right lower quadrant tenderness without rebound tenderness. Laboratory tests showed mildly elevated inflammatory markers. Abdominal CT revealed ileocolic intussusception with a well-defined lesion at the lead point demonstrating homogeneous fat attenuation (approximately -53 Hounsfield units), a finding pathognomonic for a lipoma. Emergency exploratory laparotomy confirmed an irreducible ileal intussusception into the cecum and ascending colon. An ileocecal resection with side-to-side anastomosis was performed. Pathological examination of the resected specimen confirmed a 4.0 cm × 3.0 cm × 2.5 cm submucosal ileal lipoma with overlying mucosal erosion. The patient recovered well after surgery despite a minor wound infection, and no recurrence was observed during the five-month follow-up period.

CT is the modality of choice for diagnosing ileal lipoma-induced intussusception, as it can definitively identify the pathognomonic fat-density lead point. Surgical resection remains the definitive treatment, yielding good outcomes.