[Clinical characteristics and literature review of ectopic gastric mucosa in the small intestine].

The study aims to summarize the clinical characteristics of patients with ectopic gastric mucosa in the small intestine, comparing clinical presentation differences between domestic and foreign patients through literature review. The clinical characteristics of cases diagnosed with ectopic gastric mucosa in the small intestine at Peking Union Medical College Hospital from January 2000 to January 2024 were retrospectively analyzed. By searching databanks, such as PubMed, EMBASE, the Cochrane Library, Wanfang, VIP, CNKI, and etc (the inclusion period was from the establishment of the database to January 1, 2024). The literature review was conducted on ectopic gastric mucosa in the small intestine. A total of 10 cases were included, all male, age [ (, )] was 27 (13-69) years old. Gastrointestinal bleeding was the first manifestation in most cases, with severe cases leading to hemorrhagic shock. Abdominal CT indicated local intestinal wall thickening and luminal narrowing in 3 cases. Four cases lesions were located at the beginning of the jejunum and 6 lesions were located in the end segment of ileum. All cases underwent local lesion resection, with postoperative pathology confirming ectopic gastric mucosa. Symptoms disappeared postoperatively, with a follow-up period of 0.5-3.0 years. Literature review indicates that the main clinical manifestation of gastric mucosa ectopia in the small intestine in China is gastrointestinal bleeding, while foreign patients are often complicated with intestinal duplication and intussusception, with abdominal pain and vomiting as the primary and main symptoms. The occurrence rate of intestinal obstruction in female patients, both domestically and abroad, is higher than that in male patients. The occurrence rate of ileal lesions with intestinal obstruction and small intestinal duplication is higher than that of duodenal lesions in both domestic and foreign patients. Local small intestine resection is an effective treatment method with generally good prognosis. Ectopic small intestinal mucosa is relatively rare, with symptoms of gastrointestinal bleeding and intestinal obstruction being common presentations, which can serve as one of the differential diagnoses for unexplained gastrointestinal bleeding.