SALIVARY STIMULATION MIMICS ESOPHAGEAL EXPOSURE TO REFLUXED DUODENAL CONTENTS

It has been suggested that shifts in gastric and esophageal pH can be used to estimate the reflux of injurious alkaline material, particular ly bile, into the esophagus. We sought to evaluate the contribution of swallowed saliva to alkalinization of both the stomach and esophagus in 10 normal volunteers, by performing combined gastric and esophageal pH monitoring before, during, and after salivary stimulation. The int raesophageal pH universally increased during salivary stimulation, whe reas the intragastric pH was noted to increase in six of 10 subjects. In four of these six, the pattern of simultaneous increases in esophag eal and gastric pH mimicked and could be mistaken for episodes of ''al kaline reflux.'' We conclude that the diagnosis of reflux of duodenal contents into the esophagus by pH monitoring may be compromised by fal se-positive results related to swallowed saliva.