GAST and pernicious anemia: A severe (>1000 pg/mL) elevation of fasting serum gastrin concentration is usually suggestive for Zollinger–Ellison syndrome; on top of this, the use of acid suppressant medication (both proton pump inhibitors or H2-receptor antagonists), the presence of H. pylori infection and autoimmune achlorhydric atrophic gastritis without or with pernicious anemia may lead to mild-to-moderate hypergastrinemia [4,5].