THE GRP TEST - A NEW CLINICAL-TEST OF ACID-SECRETION - REPRODUCIBILITY DATA

Objective: The gastrin-releasing peptide (GRP) test is a sensitive met hod for the detection of duodenal ulcer disease. As this test is likel y to be of value in clinical practice as well as research, this study was undertaken to assess its reproducibility. Patients and methods: A total of 14 subjects were studied; five had chronic duodenal ulcer dis ease with Helicobacter pylori infection, four were healthy volunteers with H. pylori infection and five were healthy volunteers without H. p ylori infection. Following a basal period of 45 min, GRP was infused i ntravenously at 10 and 40 pmol/kg/h, each concentration for 45 min. Bl ood samples for the determination of gastrin and gastric juice for the determination of acid output were collected every 15 min throughout t he study period. The test was repeated under identical conditions on a separate day with at least 1 week between the two tests. Results: The mean gastrin concentration at 40 pmol/kg/h GRP was 191 ng/l on day 1 (range 30-600 ng/l), and 195 ng/l on day 2 (range 33-570 ng/l). Mean a cid output at 40 pmol/kg/h GRP was 21.8 mmol/h on day 1 (range 1-58.8 mmol/h), and 22.0 mmol/h on day 2 (range 0.9-64.0 mmol/1). An estimate of the between-day coefficient of variation was 19% for gastrin and 6 % for acid. Conclusion: The GRP test is a highly reproducible test of gastric acid secretion. It provides a sensitive new tool for studying the pathophysiology of upper gastrointestinal tract diseases.