What are the other Names for this Test? (Equivalent Terms)
- Serum Gastrin Test
What is Gastrin Test? (Background Information)
- Gastrin is a hormone produced by cells (called G-cells) in the stomach, in response to increasing stomach pH (it turns less acidic), distension of stomach, or protein-rich foods
- Gastrin, in turn, increases stomach acid production. Once stomach acidity increases and food starts getting digested, the gastrin levels fall
- Gastrin Testing is done to detect the amount of gastrin hormone, present in blood. The hormone increases in conditions, such as:
- G-cell hyperplasia (increase in G-cells)
- Zollinger-Ellison syndrome (characterized by gastrin-producing tumors, called gastrinomas)
- Achlorhydria (lack of stomach acid production)
- Pernicious anemia
- Gastric outlet obstruction
What are the Clinical Indications for performing the Gastrin Test?
Indications for Gastrin Testing include:
- Conditions, such as G-cell hyperplasia (increase in G-cells) and Zollinger-Ellison syndrome (characterized by gastrin-producing tumors, called gastrinomas, commonly found in pancreas or duodenum). The excess gastrin leads to increased gastric acid production. This causes recurrent peptic ulcers with abdominal pain, nausea, vomiting, or diarrhea
- A Gastrin Testing can also be ordered, to monitor for treatment success or recurrence, following treatment of gastrinomas
- In case of suspected achlorhydria or pernicious anemia, as may occur in atrophic gastritis - the acid-producing cells of the stomach are lost in these conditions, leading to a lack of adequate stomach acid
How is the Specimen Collected for Gastrin Test?
Sample required: Blood
Process: Blood sample is drawn through a needle inserted into the vein (arm), or obtained through a finger prick.
- It is advised to avoid alcohol for 24 hours and fast for 12 hours, prior to testing
- The physician may also advise to avoid taking certain drugs, prior to testing
What is the Significance of the Gastrin Test Result?
- Fasting gastrin levels are usually below 100 pg/mL (picograms/milliliter)
- Increased levels could signify an underlying condition, leading to hypergastrinemia (increased gastrin in blood), such as achlorhydria (the most common cause, characterized by low stomach acid, due to treatment of peptic ulcer or atrophic gastritis), Zollinger-Ellison syndrome, G-cell hyperplasia, or stomach outlet obstruction
The laboratory test results are NOT to be interpreted as results of a "stand-alone" test. The test results have to be interpreted after correlating with suitable clinical findings and additional supplemental tests/information. Your healthcare providers will explain the meaning of your tests results, based on the overall clinical scenario.
Additional and Relevant Useful Information:
- Gastrin levels may be increased with long-term use of antacids and with an advancing age
Certain medications that you may be currently taking may influence the outcome of the test. Hence, it is important to inform your healthcare provider, the complete list of medications (including any herbal supplements) you are currently taking. This will help the healthcare provider interpret your test results more accurately and avoid unnecessary chances of a misdiagnosis.