Rectosigmoid intussusception due to large submucosal lipoma mimicking rectal prolapse

Abstract

Rectosigmoid intussusception is a rare cause of bowel obstruction, accounting for only approximately 1%-2% of all bowel obstruction cases. While intussusception in adults typically occurs intra-abdominally and presents with signs and symptoms of intestinal obstruction, in rare cases, it can mimic a rectal prolapse if the intussusceptum protrudes through the anal canal. We herein report a case where an octogenarian woman presented with rectosigmoid intussusception through the anal canal, due to a sigmoid colon submucosal lipoma, who eventually required an open Hartmann's procedure. Patients with rectal prolapse symptoms should be carefully examined to rule out intussuscepting masses as a differential, as it would necessitate earlier surgical intervention.

Keywords: Gastrointestinal surgery; General surgery.

Figure 1

Clinical photo of rectal mass.

Figure 2

Supine abdominal radiograph shows generalised colonic dilatation.

Figure 3

(A) A focal fat-density lesion prolapses externally, suggesting the lead-point. (B) Coronal post-contrast CT sections show intussusception at the sigmoid colon.

Figure 4

(A) Intraoperative photo showing rectosigmoid intussusception. (B) Intraoperative photo showing perforation of proximal sigmoid colon after reduction.