Effect of betazole on serum group I pepsinogen levels: relationship to gastric acid output in unoperated and postoperative patients.

A significant association has previously been found between a betazole-induced decrease in serum group I pepsinogen (PG I) levels and a low peak acid output (PAO) in symptomatic patients with vagotomy and gastric resection or a drainage procedure. This study compares the effect of betazole on serum PG I levels and gastric acid output in 245 unoperated patients (115 duodenal ulcer, 25 prepyloric ulcer, 32 gastric ulcer, 73 nonulcer) and in 73 symptomatic postoperative patients (15 subtotal gastric resection, 28 vagotomy and gastric resection, 30 vagotomy and drainage). A negative serum PGI response (2-hr serum PG I level less than 92% of basal) occurred in 10 (4.1% of the unoperated patients and in 31 (42.5%) of the postoperative patients. Seven (70%) of the former and 29 (93.5%) of the latter patients had a PAO of less than 10 mEq per hr, indicating that a negative serum PG I response is associated with a low PAO in both unoperated and postoperative patients. The PAO was greater than 10 mEq per hr in 93.1% of the 277 patients with a 2-hr serum PG I level of more than 92% of basal. Additional studies revealed that neither aspiration of gastric juice nor perfusion of the stomach with acid altered the serum PG I response. This suggests that topical acid does not modulate the effect of betazole on serum PG I levels. Finally, a negative serum PG I response has been shown to be paradoxical, in that gastric pepsin levels have been found to increase over basal concurrently with the decrease in serum PG I levels.