Abstract
A Cambridge combined glass electrode was used to determine the intraluminal pH of the duodenum and upper jejunum. Correlation between the intraluminal pH thus obtained and that of aspirates was poor. The reasons for concluding that the electrode in situ provided the more reliable measurement are discussed. Variations outside the normal range in normal subjects were noted in the presence of gastric hypersecretion and in pancreatic achylia and in adult coeliac disease.