Marginal ulcer perforation after one anastomosis gastric bypass: a case report.

One anastomosis gastric bypass (OAGB) has gained popularity and it is currently the third most frequently performed bariatric procedure worldwide. A marginal ulcer (MU) at the anastomosis site between the gastric pouch and the small intestine is a common complication of gastric bypass procedures but a rare complication of OAGB. Risk factors for MUs include cigarette smoking, alcohol misuse, and infection.