[Contribution of per- and trans-endoscopic pH measurements to the exploration of the upper digestive tract (author's transl)].

Per- and trans-endoscopic pH measurements in the upper digestive tract have provided new and interesting data. Performed by the authors on a series of 314 patients, they showed that the gastric pH is seldom acid, even in duodenal ulcer, and is always alkaline in gastric ulcer and gastric carcinoma. Gastritis may be divided into two groups, depending on whether the pH is normal or hypoacid (4.5 in the antrum, 2.5 in the fundus). Biopsies demonstrated the presence of intestinal metaplasia and epithelial dysplasia in 57.8% of 83 patients with hypoacid gastritis. The method therefore constitutes a simple and reliable means of determining markers of precancerous lesions.