Clinical usefulness of gastric acidity studies.

Tests of gastric secretion are seldom diagnostic in the investigation of gastric and duodenal ulceration, but they can provide evidence that is helpful in arriving at a diagnosis. Common tests include basal acid output, pentagastrin-stimulated maximal and peak acid output, and the Hollander test. There is some evidence that they may be useful in selecting the type of operation for peptic ulceration. Indications for performing these tests relate to the Zollinger-Ellison syndrome, duodenal ulcer, recurrent dyspepsia after operation for duodenal ulcer, and decisions concerning the choice of operation for peptic ulcer. In order to perform these functions they must be properly conducted and interpreted; they are simply an adjunct to clinical judgement, and complementary to other laboratory tests.