I. Gastrin-secreting tumor (or tumors) from non-beta islet cells of pancreas results in greatly increased gastric HCl production

II. Tumors are usually unresectable; sometimes too small to find; about 2/3 are malignant

III. Although the hallmark is ulcers in wider geographic distribution than normal, 75% of ulcers in Z-E sd are single ulcers in the duodenal bulb.

IV. 1/3 of pts have diarrhea, which usually precedes ulcer development; 7% have diarrhea and never develop and ulcer

V. Consider dx especially when ulcers are

  1. Refractory to med. therapy
  2. Giant
  3. Multiple
  4. Not limited to duodenal bulb
  5. Located in a surgical anastomosis
  6. Associated with diarrhea not secondary to drugs

VI. Dx based on serum gastrin concentration > 1000 pg/ml (nl < 150)

  1. Causes for moderately elevated gastrin ( < 1000): retained antrum after gastric surgery, g-cell hyperplasia, postvagotomy plus pyloroplasty, pernicious anemia, and a small proportion of nl pts with DU
  2. Make sure to stop H2 blockers > 12h before measuring gastrin b/c will raise it
  3. Provocative tests can confirm:
  1. Secretin infusion test: in Z-E, gastrin level rises < 1/2 after injection of secretin; if not, it remains steady or falls
  2. Gastric acid monitoring with pentagastrin infusion: basal: maximal acid output > 0.6 suggests Z-E


  1. Gastrectomy traditional tx of choice
  2. Highly selective vagotomyis also used
  3. High-dose H-2 blockers or omeprazole are used to calm things down before surgery