In 36 patients with verified
hyperparathyroidism (HPT), serum
gastrin and its response to
secretin was studied before and after
parathyroidectomy. In most of the patients gastric secretion-basal
acid output (BAO) and maximal
acid output (
MAO)--was also studied. Seventeen patients had increased serum
gastrin values preoperatively and/or postoperatively. Most of the serum
gastrin increases were moderate and all but one of the patients with values above 250 pmol/l had
hypochlorhydria. Nine patients had a positive
secretin test according to conventional criteria preoperatively or postoperatively, but showed no other signs suggestive of a
gastrin-producing tumour. Most of the patients with a serum
gastrin increase after injection of
secretin had
hypochlorhydria or
achlorhydria. The BAO/
MAO ratio was less than 0.6 in all patients. The results of this study do not support the view that primary HPT is often associated with a
gastrin-producing tumour as part of a
multiple endocrine adenomatosis (MEA type I), but indicate that the observed hypergastrinemia in HPT is almost exclusively related to hypo- or
achlorhydria. The findings also give reason to doubt the value of the
secretin test.