1st order laboratory parameters – obligatory laboratory tests.
- Gastrin level* basal Note: A normal serum gastrin does not exclude gastrinoma!Common differential diagnoses of hypergastrinemia include:
- Taking proton pump inhibitors (PPI).
- Chronic atrophic type A gastritis
- Helicobacter pylori-associated gastritis
- Gastrin stimulation test – gastrin basal and post secretin (secretin test)Test requirements: PPI pause for 10-14 daysTest performance: blood sampling for gastrin determination at time points -15 and -1 min before secretin administration and at time points 2, 5, 10, 15, 20 and 30 min after secretin administration (bolus injection of 2 IU/kgKG i. v.)Interpretation:A delta increase in serum level of gastrin >120 pg/ml and >200 pg/ml, respectively, has high diagnostic sensitivity and specificity for the presence of gastrinoma.
* Notes for sample collectionBlood collection in the morning fasting (circa 12 hours of food abstinence); 24 hours before blood collection no ingestion of:
- Antacids – gastric acid-binding drugs such as aluminum hydroxide.
- H2 blockers – gastric acid secretion inhibitors such as cimetidine, ranitidine.
- Anticholinergics – drugs that inhibit the transmitter acetylcholine; these include atropine or butylscopolaminium bromide.
- Not drinking coffee
