Serum immunoreactive gastrin in rheumatoid arthritis. Further observations on its identity, clinical specificity, and relationship to gastric function.

Serum immunoreactive gastrin is raised in some patients with rheumatoid arthritis (RA). In this paper paired samples taken within 30 minutes of each other show that this phenomenon is reproducible. Dilution curves show identity between gastrin from RA patients and from patients with no RA, and the raised immunoreactive gastrin concentration is demonstrable in patients who do not have chronic atrophic gastritis and in whom both basal and stimulated acid output concentrations are normal. Samples of gastric mucous membrane obtained from the body of the stomach and gastroscopy under direct vision in 18 patients with raised serum immunoreactive gastrin concentrations were normal.