Inflammatory fibroid polyp presenting as intussusception
A 41-year-old lady presented to the Emergency Department on four different occasions with a 3-month history of intermittent epigastric pain. There was no relevant past medical history, no family history of colorectal carcinoma and her only previous surgery was a laparoscopic appendectomy 3 months earlier for acute appendicitis.\nOn her third presentation to the Emergency Department, she underwent an abdominal ultrasound, which displayed gross thickening of presumed large bowel (caecum/ascending colon) 48 mm in diameter and 114 mm in length. On examination, a palpable mass in the right lower quadrant was noted. However, her symptoms resolved and she was discharged home without further investigation.\nShe represented one week later with severe abdominal pain associated with vomiting, poor oral intake and not opening her bowels or passing flatus for one week. On this presentation, a small bowel obstruction with multiple air fluid levels was evident on abdominal x-ray. A CT abdomen was performed, which demonstrated a target-shaped soft tissue mass pathognomonic of intussusception (as shown in Fig. ).\nA subsequent laparotomy through a midline incision showed clear free peritoneal fluid and an ileocolic intussusception (as shown in Fig. ).\nShe underwent a right hemi-colectomy with a side-to-side ileocolic anastomosis. She received Total Parental Nutrition post-operatively for malnutrition and was discharged home following an uneventful post-operative recovery.\nMacroscopic examination revealed a polypoid lesion measuring 25 by 10 mm, located within the terminal ileum 180 mm from the ileocaecal valve (as shown in Fig. ).\nThe polyp was confined to the bowel submucosa with no extension into the muscularis propria. Associated with the lesion there was localized mild predominantly chronic inflammatory cell infiltrate. Immunohistochemistry performed on this lesion was negative for S100, desmin and CD 117, effectively excluding a neurogenic tumour, gastrointestinal stromal tumour and a submucosal leiomyoma. Spindled cells within the submucosa expressed CD34 (weak to intermediate expression). This case lacks the myxoid stroma and perivascular concentric arrangement of inflammatory cells, which is best described in the stomach (as shown in Fig. ). These features favour a terminal ileal inflammatory fibroid polyp, which was responsible for the intussusception and subsequent small bowel obstruction.