McSwain type V appendix intussusception

Description

Intestinal intussusception consists of distal migration of a segment from the intestine to the adjacent intestinal lumen. Appendicular intussusception (AI) is a rare disease that constitutes a clinical challenge. The incidence of AI is estimated at 0.01%.¹ It is five times more frequent in men.² Despite imaging and endoscopic advances, diagnosis remains a difficult challenge. The presentation of AI varies from asymptomatic to chronic pain.³ This case reports a 33-year-old woman with past gastro-oesophageal surgery and complementary appendectomy, which was evaluated for the chronic pain in the right lower quadrant. Colonoscopy (figure 1A,B) revealed intussusception of appendix type V. A laparoscopic caecum resection was performed. The postoperative was uneventful. Histology revealed AI with lumen obliteration by foreign body (suture of previous intervention).

Figure 1.

Colonoscopy: (A, B) finger-like polypoid tumour.

McSwain’s classification is anatomical based on the region of the appendix that undergoes intussusception. Type V is defined as a complete invagination of the appendix in the caecum.¹ The anatomical causes are (a) mobile appendicular wall, capable of presenting active peristalsis; (b) large appendicular lumen, with the proximal lumen of larger diameter than that of the distal portion; and (c) foetal-type blind.² Pathological causes are (a) foreign body—fecaliths or parasites; (b) inflammation—endometriosis or follicular lymphoid hyperplasia; (c) neoplasia—carcinoid tumour, carcinoma, mucocele, polyp, papilloma, fibroma, lipoma, cysts or blind adenocarcinoma; and (d) invagination of the appendiceal stump after appendectomy.⁴ The approach can range from simple appendectomy to right colectomy if there are signs of obstruction.¹

Learning points.

• AI should be considered in the workup of chronic abdominal pain in women.

• AI is a preoperative diagnosis, aided by colonoscopy.