In short
- The stool test and the breath test show an active infection. Blood antibodies only show that you were in contact at some point.
- Stop acid blockers two weeks before, and antibiotics and bismuth four weeks before. Otherwise the result will be falsely negative.
- Antibodies are not suitable for checking whether treatment worked, because they stay positive long after the infection is cured.
- With alarm signs — weight loss, trouble swallowing, vomiting blood, black stool, anaemia — do not test, see a doctor.
- The check after treatment is done at least four weeks after the end of antibiotics, with a stool or breath test.
Helicobacter pylori is a bacterium that lives in the stomach lining. In some people it causes ulcers and long-term inflammation. The choice of test decides whether you get a useful answer or false reassurance.
What the infection causes and what it does not
The infection is common, and in a large share of people it causes no trouble. In some, it leads to inflammation of the stomach lining or a stomach or duodenal ulcer. In the long run it raises the risk of stomach disease. That is why the rule is simple: a proven infection is treated, even without symptoms.
The most common signs are a burning or dull pain in the upper belly, a feeling of fullness after a small meal, nausea and bloating. These signs are not specific. The same picture occurs with reflux, functional dyspepsia and some medicines.
The infection is passed on mainly in childhood, within the household. If the infection is proven in one family member, testing the partner makes sense. With children, the paediatrician decides.
Three tests and what each one tells you
| Test | What it shows | What it is suitable for |
|---|---|---|
| Stool antigen | An active infection now. | First testing and the check after treatment. Simple sample collection at home. |
| Urea breath test | An active infection now. | First testing and the check. Requires a visit and preparation. |
| IgG antibodies in blood | That you were in contact with the bacterium at some point. | Limited. Does not separate a current infection from a past one and is not suitable for the check. |
| Endoscopy with biopsy | The infection and the state of the lining. | With alarm signs, in older people and after failed treatment. |
The most common mistake: positive blood antibodies are taken as proof of an infection that must be treated right away. Antibodies stay positive for months to years after successful treatment. So a positive result without a stool or breath test is not confirmation.
What to stop before the test
This is the one part where a mistake ruins the result completely. Acid blockers and antibiotics suppress the bacterium for a while but do not wipe it out. So the test comes back falsely negative.
- Proton pump inhibitors (for example pantoprazole, omeprazole, esomeprazole): stop two weeks before.
- Antibiotics and bismuth preparations: four weeks before.
- H2 receptor blockers and antacids: usually do not need to be stopped, but say what you are taking.
- Never stop a medicine on your own if a doctor prescribed it for an ulcer or bleeding. In that case, agree it with the doctor.
If stopping is not possible, it makes more sense to postpone the sample than to get a result that tells you nothing.
When not to test, but to see a doctor
- Unintended weight loss.
- Difficult or painful swallowing.
- Vomiting blood or black, tarry stool.
- Unexplained anaemia or a positive bowel-cancer screening (Svit) result.
- Repeated vomiting or a lump you can feel in the belly.
- First onset of symptoms after age 50.
In these cases the right step is endoscopy, not a self-paid test. A stool test could come back negative and the cause would stay undiscovered.
After treatment
A doctor prescribes the treatment. It usually lasts ten to fourteen days and combines antibiotics with an acid blocker. Because the bacterium's resistance is rising in Europe, checking that treatment worked is mandatory, not optional.
- Check at least four weeks after the last dose of antibiotic.
- Two weeks without an acid blocker before the check, otherwise the result is falsely negative.
- Check with a stool or breath test, never with antibodies.
If the check is positive, the treatment did not work and the doctor chooses another combination. This is not rare and not a reason to worry. But it is a reason to do the check.
Frequently asked questions
Which Helicobacter test is best?
The stool antigen or the urea breath test, because they show an active infection. Blood antibodies only show past contact and are not suitable for the check.
How long before do I have to stop my medicines?
Acid blockers two weeks, antibiotics and bismuth four weeks. Without this the result will be falsely negative. If a doctor prescribed the medicine, agree the pause with them.
Does the infection need treating if I have no symptoms?
Usually yes. A proven infection is treated even without symptoms, because in the long run it raises the risk of stomach disease. The decision and the prescription rest with the doctor.
When should I do the check after treatment?
At least four weeks after the last antibiotic and after two weeks without an acid blocker, with a stool or breath test.
Should my partner be tested too?
If the infection is proven in you, testing the partner makes sense, because the infection is passed on within the household.
Sources: Maastricht VI / Florence — management of H. pylori infection, choice of test, stopping acid blockers two weeks and antibiotics four weeks before the test, mandatory check that treatment worked · ESPGHAN — management in children · BSG — alarm signs that require endoscopy.
