Discriminative Interest of the Study of Basal Acid Secretion and Pepsin Acid Correlation in Zollinger-Ellison Syndrome and Peptic Ulcer

Abstract

Various criteria based upon study of basal acid and pepsin gastric secretion have been proposed to facilitate the diagnosis of Zollinger-Ellison (ZE) syndrome. These criteria have been analyzed on 599 gastric secretory studies on subjects who had undergone no gastric surgery. This population included 20 ZE syndromes and 495 duodenal ulcers (DU). Neither an acid concentration > 100 mEq/l nor an acid output > 15 mEq/h is sufficiently discriminatory for the diagnosis of ZE syndrome when taken alone because they were found in 8.2 and 6% of DU, respectively. However, the association of these two criteria in the same secretory study strongly increases the suspicion of this diagnosis because it was found in 60% of ZE syndrome cases and in only 2.8% of DU. A valuable modification of those criteria taken alone is the presence of a basal acid output > 18 mEq/h. In the present series, however, the most interesting criterion has proved to be a pepsin/acid correlation (K 25) equal to or lower than 35. In any case, a low pepsin/ acid correlation improves the suspicion of the diagnosis. The most characteristic secretory status of the ZE syndrome consists of an association of a basal acid output > 18 mEq/h, a basal acid concentration > 100 mEq/l and a K 25 < 35 which is found in 55% of ZE syndrome cases and in only 0.6% of DU without pyloric stenosis. These criteria have to be considered as a means of selection of patients in whom radioimmunoassay of serum gastrin is needed.

Current approach to the management of tumoral process in patients with gastrinoma

“…One hundred seventeen patients (81%) had a demonstrated tumoral process at surgery (108 cases) or by unequivocal finding of preoperative imaging techniques or at autopsy (9 cases). Ten patients had islet-cell hyperplasia at histological examination of blind distal pancreatic resection, associated with clinical abnormalities highly suggestive of ZES [8,9]. In 17 cases, no anatomical findings were made, but these individuals had typical clinical symptoms and presented biological abnormalities specific for ZES, i.e., basal acid output -26 mmol/hr; mean basal serum gastrin >-226 pg/ml, and positive secretin test as determined by our institution [10].…”

Pepsin acid correlation in patients with Zollinger-Ellison syndrome.

“…Hunt (1967) reported that in 2 cases of ZollingerEllison syndrome acid secretion was about 10 times greater than expected for the corresponding pepsin secretion. Bernades et al (1973) stated that pepsin acid correlation K25 (pepsin output per 25 ml of primary acid secretion) in cases of Zollinger-Ellison syndrome differed significantly from controls and patients with duodenal ulcer and gastric ulcer. They also reported that in any case, a low pepsin acid correlation K25 less than 35 increases the suspicion of the diagnosis of Zollinger-Ellison syndrome.…”