Estimate of gastric acid output by evaluation of fasting gastric juice collected endoscopically.

Using an endoscope we collected fasting gastric juice for estimation of gastric acid in subjects examined by upper gastrointestinal endoscopy. Subjects were 53 in- and out-patients (46 males and 7 females) at our hospital. Seventy-five gastric secretory studies were performed in this population before and after stimulation by tetragastrin, following the guidelines of The Japanese Society of Gastroenterology and using a specially devised endoscope of narrow caliber under direct vision. Acid in fasting gastric juice was correlated with basal acid output (BAO) and with maximal acid output (MAO). There was a statistically significant correlation between them. Thus, an estimation of gastric acid secretion can be obtained from the fasting gastric juice which we usually aspirate and discard during the routine endoscopic examination.