Rectosigmoid Intussusception Due to a Nonmalignant Etiology: An Extremely Rare Cause of Acute Lower Gastrointestinal Bleeding in an Elderly Patient.

An intussusception at the rectosigmoid junction with acute gastrointestinal bleeding is exceedingly rare. We present a case of an 88-year-old man who presented in the emergency department with bilateral lower quadrant abdominal pain and frank rectal bleeding for 2 days. A computed tomography abdomen pelvis angiogram with contrast showed a target sign, and a flexible sigmoidoscopy showed congested bowel, ischemia, frank blood, and intussusception at the rectosigmoid junction. He underwent an exploratory laparotomy with the removal of the affected part. The pathology and the peritoneal fluid cytology results came out negative for dysplasia and malignancy.