Esophageal Acid Clearance Function in Reflux Esophagitis

Background/Aims: Esophageal acid clearance is an important mechanism protective against the development of reflux esophagitis. Acid clearance from the esophagus after gastro-esophageal reflux depends on two important mechanisms: esophageal peristalsis to return the displaced gastric content to the stomach and swallowed saliva to neutralize the residual acid that coats the esopha- gea1 mucosa. The present study aims to investigate acid clearance and determine the contributions of esophageal peristalsis, salivation, and gravity. Methods: We performed the acid clearance test, ambulatory 24 hour esophageal pH study, esophageal manometry and saliva study in 16 consecutive patients with reflux esophagitis, and then compared them with normal controls. Results: The clearance of acid instilled into the esophagus was markedly delayed in patients with reflux esophagitis as compared with controls(p0.05). There was a trend towards a lower peristaltic amplitude in patients with reflux esophagitis, but this was statistically not significant. Of the motor events analyzed, there were simultaneous contractions in 4 patients(25.0%), poor wave progression in 4 patients(25.0%), and non-transmitted contraction in 2 patients(12.5%). In patients with reflux esophagitis, the number of reflux episodes, the mean number of reflux episodes greater than 5 minutes, and the percentage of time when the pH was less than 4 were significantly increased compared with controls(p