The presence of ectopic gastric mucosa in the small bowel is usually associated with congenital anomalies such as Meckel's diverticulum, 1 jejunal diverticula 2 or duplication of the small bowel. 3 The presence of ectopic gastric mucosa in the small bowel without these congenital anomalies is extremely rare. Hereby, we report an adult man who presented with mechanical intestinal obstruction caused by an ectopic gastric mucosal ulcer in the jejunum without congenital anomaly.A 39-year-old man was presented to the emergency department of our hospital complaining of central abdominal pain and distension associated with repeated vomiting of 1-day duration. He had no previous abdominal surgery. The patient had milder similar attacks in the last year that subsided with analgesia. On examination, he had blood pressure of 128/69 mmHg, pulse rate of 78 beats per minute and temperature of 36.8°C. The abdomen was mildly distended and tender, but soft and lax. Bowel sounds were exaggerated. There were no abdominal surgical scars or hernia detected. Blood investigations showed leukocytosis of 20.1 × 10 9 /L and high C-reactive protein (28 mg/L).Erect and supine abdominal X-rays showed multiple air fluid levels and dilated proximal jejunal loops. Abdominal ultrasound confirmed the presence of distended small bowel loops without intraperitonealfree fluid. Abdominal computed tomography scan with oral and intravenous contrast showed a dilated segment in the mid-jejunum with sharp transition to normal diameter. There was no intraabdominal mass. The picture was suggestive of mechanical obstruction of the small bowel. A gastrografin meal follow-through study showed dilated jejunal loops without visualization of the ileum or colon 7 h after taking the oral contrast. A decision for laparotomy was made. At laparotomy, there was stenosis in the mid-jejunum (Fig. 1). Interestingly, this narrowing easily gave away when examined between the thumb and index finger of the operating surgeon. There was no evidence for any diverticula or other anomaly of the gastrointestinal tract. Resection of the stenosis and end-to-end anastomosis of the small bowel was performed in two layers using vicryl 3/0.The excised jejunum showed an annular raised mucosa, with superficial erosion on the anti-mesenteric border (Fig. 2). Histopathology of the excised jejunum showed a deep penetrating mucosal ulcer in an area of ectopic gastric mucosa with underlying fibrosis in the submucosa and the muscularis propria (Fig. 3). The postoperative period was smooth and the patient was discharged home 5 days after surgery. Follow-up of the upper gastrointestinal endoscopy 6 weeks later showed mild antral gastritis without duodenal ulcer. Histopathology of biopsies taken showed mild chronic inflammation without Helicobacter pylori. The patient was followed up 3 years after surgery and he was asymptomatic. Fig. 1. Laparotomy revealed a stenosis in the dilated mid-jejunum. Fig. 2. Small intestinal mucosa in which there is slight nodularity and congestion of the surface with f...