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Jejunal gastric heterotopia presenting as perforation peritonitis in a middle-aged adult: A case report

Highlights • Jejunal gastric heterotopia rarely occurs and is usually congenital.• Jejunal gastric heterotopia can be a rare cause of perforation peritonitis in adults.• Our case is the presumed oldest jejunal gastric heterotopia patient presenting with perforation peritonitis ever reported.


Presentation of case
A 51-year-old male presented with abrupt onset abdominal pain of 1 day duration after eating a meal. At that time, the patient has been treated for pulmonary tuberculosis. He has had no drug history, allergies or specific family history. The patient felt some chills and did not have any fever. Physical examination was notable for abdominal tenderness and rebound tenderness as well as costovertebral angle tenderness. Abdominal computed tomography demonstrated pneumoperitoneum suggestive of hollow viscus perforation. Emergency laparotomy was performed by a fully qualified gastrointestinal surgeon in a university hospital. At laparotomy, a perforation site was discovered in the jejunum 100 cm distal to the ligament of Treitz. The size of perforation site measured less than 0.5 cm. Segmental resection of the jejunum with sideto-side anastomosis was performed. The resected jejunal segment measured 8 cm in length which secured appropriate margin of normal mucosa around the perforation site. Macroscopic examination revealed a 3 × 4 cm ill-defined shallow ulceration next to the perforation site ( Fig. 1). There was no evidence of an associated diverticulum or intestinal duplication. Microscopically, the perforation site showed a perforated chronic ulcer and peritonitis ( Fig. 2A). The intestine around the perforation site revealed heterotopic gastric mucosa with markedly thickened proper muscle and dense subserosal fibrosis (Fig. 2B). The gastric heterotopia composed of gastric foveolar epithelium along with abundant pyloric glands and a few fundic glands (Fig. 2C, D). The heterotopic gastric mucosa was associated with erosions and shallow healed ulcers without any polypoid masses. The pyloric glands were diffusely immunoreactive to the MUC6 antibody. Postoperatively, the patient has had no

Discussion
Gastric heterotopia of the gastrointestinal tract occurs commonly in the esophagus and duodenum [8]. Gastric heterotopia of the small intestine beyond the ligament of Treitz is mainly associated with congenital diverticulum and intestinal duplication [9,10]. Gastric heterotopia of the small intestine beyond ligament of Treitz without an associated congenital diverticulum or intestinal duplication is rare [11,12], and most of the cases are reported in children and young adults [1][2][3][4][5][6]. The most common clinical presentations of jejunal gastric heterotopia are associated with polypoid lesions causing intermittent intussusception [2], gastrointestinal bleeding [3] and obstruction [1]. Peptic ulceration in the area of heterotopia can cause stricture and perforation [13]. Although rare, extensive gastric heterotopia of small intestine can result in massive bleeding, bowel perforation, and death [12].
Gastric heterotopia should be differentiated from gastric metaplasia which is an acquired lesion associated with chronic inflammation and only occupies part of mucosal thickness [6]. Microscopically, gastric heterotopia consists of surface foveolar epithelial cells along with pyloric and fundic glands whereas gastric metaplasia consists of only foveolar epithelial cells without fundic glands [8,11].
Up to our knowledge, the oldest patient with jejunal gastric heterotopia reported in the English literatures was a 52-year-old woman [14] who presented with symptoms of intermittent cramping, abdominal pain, and vomiting due to polypoid mass of jejunal gastric heterotopia . The patient [14] had previously undergone surgery for Meckel diverticulum at age 22. To the best of our knowledge, our case is the presumed oldest jejunal gastric heterotopia patient presenting with perforation peritonitis ever reported. The later clinical presentation in our case may be partially related to the fact that our case presented as a non-mass forming lesion with only tiny amount of parietal cells.

Conclusion
Although jejunal gastric heterotopia rarely occurs, it should also be considered in the differential diagnosis of perforation peritonitis in adults.

Declaration of Competing Interest
The authors report no declarations of interest.

Sources of funding
None.