Gastric Epithelium in the Duodenum

Abstract

EDITORIAL SYNOPSIS It has been found that a 'gastric' type of epithelium tends to develop in the first part of the duodenum in patients with duodenal ulceration and is found in the second part of the duodenum in a patient with the Zollinger-Ellison syndrome. It is likely that 'gastric' epithelium appears when the duodenal acidity is high and it is resistant to ulceration.The stomach is normally lined by one kind of epithelium and the duodenum by another. Islands of intestinal epithelium have long been known to occur in the stomach, particularly when gastric acidity is low: this paper describes islands of gastric epithelium in the duodenum; they are especially common when gastric, and hence duodenal, acidity is high. These anomalies mirror each other, and the conditions which bring them about throw light, it will be suggested, upon the pathogenesis of peptic ulceration and the determination of its site.Taylor (1927), reviewing heterotopia in the alimentary tract, described two instances of gastric epithelium in the duodenum. They were found among 150 necropsies, and were recognizable as slightly raised patches. Histological examination showed these to be covered by well-preserved gastric epithelium and to contain gastric glands with both chief and parietal cells; Brunner's glands were absent from the patches. In both cases the patches were found in the first part of the duodenum near the pylorus, and in one there was a duodenal ulcer. The presence of gastric glands places these patches in a different category from those described in this paper, where only the epithelium was abnormal. Patzelt (1936) reviewed the histology of the pyloro-duodenal region in animals and man and quoted descriptions which showed that the line of epithelial demarcation was not always sharp, there being islands of intestinal epithelium on the gastric side of the pylorus and, much more rarely, of gastric epithelium on the intestinal side. His article contains an illustration of one such 'Magenepithelinsel' found in the duodenum of a woman; the island appears to cover an inflammatory polyp containing a lymph follicle; no gastric glands were present.