Adult idiopathic ileosigmoid intussusception prolapsing per rectum.

Ileosigmoid intussusception can lead to ischemia and necrosis of either the ileum or sigmoid colon. Ileosigmoid intussusception as a mass prolapsing per rectum in an adult has not been previously reported. We report a 50-year-old man with such a presentation. He recovered uneventfully after subtotal colectomy.