What it measures
Proteins (antigens) from Helicobacter pylori in a stool sample. Finding them shows the bacteria are in the gut now. H. pylori can live in the stomach lining and is linked to stomach ulcers and indigestion.
Why people test it
- Investigating indigestion, stomach pain or a stomach ulcer.
- Checking whether H. pylori is still present after a course of antibiotics.
Typical range
There is no numeric range. The result is reported as positive or negative (sometimes detected or not detected). Labs and kits word this differently, and the report or kit shows how the result is given.
Finger-prick or vein?
This is not a blood test. Providers offer it only as a home kit using a stool sample.
Acid-reducing medicines called proton pump inhibitors in the 2 weeks before the test, or antibiotics in the 4 weeks before, can give an inaccurate result.