Histological findings revealed gastric mucosa probably arising from Meckel diverticulum caused invagination.
Case 310
【Progress】
Operative findings found invagination of swollen ileum lying on top one another. The advanced portion of invagination was a small mass palpated like a tumor. Histologic examination did not reveal a tumor mass but an ectopic gastric tissue probably arisen from Meckel diverticulum.
【Discussion】
It is reported that large intestine invagination (intussusception) arises from malignant lesion while small intestine invagination arises from benign lesion (1, 2). In other words, the leading point of large intestine invagination is often found to be carcinoma while the leading point of small intestine varies such as polyp, myoma, hemangioma, ectopic pancreas, ectopic gastric mucosa and Meckel diverticulum (3-6).
Meckel diverticulum is a remnant of a vitelline duct that occurs in 2% of population and situates at 2 feet (61cm) from ileum end and sized 2 inch (5 cm) (3-6). When vitelline duct remains like a string, it can cause small bowel obstruction. In case of no previous history of surgical operation, vitelline duct remnant is listed as one of causes of small bowel ileus. Meckel diverticulum can contain ectopic gastric mucosa and/or ectopic pancreas tissue, causing ulcer or bleeding. Further, Meckel diverticulum can be responsible for small intestine invagination.
In our case, ileum invaginated to colon lumen inducing CT depicted target sign in the ascending colon, namely, small intestine edematous mural entered colon lumen with mesentery. It really induced us to interpret the presence of invagination to pursuit the progress of adipose tissue of mesentery. Histologic examination revealed ectopic gastric mucosal layer. Ectopic gastric layer least occurs in small intestine but in Meckel diverticulum. Then, the gastric muscle layer is thought to be arisen from Meckel diverticulum.
【Summary】
We presented a forty-seven-year-old inpatient who complained abdominal pain this morning. Abdomen CT depicted small intestine invaginated to ascending colon whose lead point was not unknown. Histological examination of surgical resected specimen revealed gastric mucosal layer of the leading point. It is borne in mind that small intestine invagination comes from benign tumors such as polyp, myoma, hemangioma, polyp or Meckel diverticulum while colon invagination comes from carcinoma. Meckel diverticulum sometimes include ectopic pancreas and gastric mucosa , inducing ulcer and bloody stool in children. Meanwhile, in adults, small bowel obstruction occurs due to remnant of vitelline duct with Meckel diverticulum and invagination as a leading point.
【References】
1.Martín-Lorenzo JG, et al. Intestinal invagination in adults: preoperative diagnosis and management. Int J Colorectal Dis. 2004;19:68-72.
2.Ito T, et al. Adult intussusception caused by an inverted Meckel diverticulum. Case Rep Gastroenterol, 5 (2011), pp. 320-324,
3.St-Vil D et al. Meckel's diverticulum in children: a 20-year review. J Pediatr Surg.1991; 26:1289-1292,Martín-Lorenzo JG, et al. Intestinal invagination in adults: preoperative diagnosis and management. Int J Colorectal Dis. 2004 Jan;19(1):68-72.
4.Furukawa K, et al. Adult intussusception caused by Meckel's diverticulum complicated by anisakiasis of the small intestine: report of a case. Clin J Gastroenterol. 2014 Aug;7(4):316-9
5.Wesley E. et al. Small bowel intussusception secondary to inverted Meckel's diverticulum. Journal of Pediatric Surgery Case Reports. 2017;25:49-51
6.Lima M, et al. An unusual case of intramural Meckel's diverticulum as a lead point for ileoileal intussusception – laparoscopically assisted management. J Pediatr Surg Case. 2013; 1:111-113,
2023.9.13