Occurrence of a Duodenal Polypoid Lesion During Long-Term Acid Suppression Therapy and Its Regression After Drug Discontinuation

Formation of multiple fundic gland polyps or hyperplastic polyps in the gastric mucosa is one of the well-known adverse effects of the long-term acid suppression therapy for peptic ulcer disease. However, similar phenomenon has not been reported to occur in the duodenum. We report a case of duodenal polypoid lesion that developed after the long-term use of acid suppressants and disappeared after the cessation of the treatment. The patient was a 76-year-old man with a history of heavy cigarette smoking and excessive alcohol intake who had been treated with medication of gastric acid suppressants, including proton pump inhibitors and potassium-competitive acid blockers, for refractory gastroesophageal reflux disease. After receiving the acid suppression therapy for 3 years, a polypoid lesion of 10 mm in diameter was found at the portion of the duodenal bulb. This polypoid lesion disappeared 1.5 months after the cessation of treatment. We hypothesized that changes in serum gastrin levels caused by acid suppression therapy might have been associated with the development and regression of the duodenal polypoid lesion.