A 36-year-old male visited Tsuchiura Kyodo General Hospital because of epigastric discomfort. Endoscopic findings revealed a flat elevation with granular appearance in the duodenal bulb just anal to the pyloric ring. After spraying Congo Red, the color turned to black promptly, suggesting avid secretion of acid by the elevated mucosa. Pathological examination showed fully developed fundic mucosa. A diagnosis of ectopic fundic mucosa in the duodenal bulb with acid secretion was made.
Helicobacter pylori was not detected by rapid urease test, culture, or microscopic examination. The IgG anti-Helicobacter pylori antibody was also negative. Additionally, almost whole gastric mucosa was fundic gland type, and had the ability to secrete acid. There have been no report of a case of ectopic acid-secreting gastric mucosa in the duodenal bulb without Helicobacter pylori infection. The lack of pyloric gland in this patient may have inhibited the infection.
