Helicobacter pylori antigen in stool (qualitative)
This test checks for the presence of *Helicobacter pylori* bacteria in your stool. It helps determine if you have an infection caused by this common stomach bacteria, which can lead to stomach ulcers or other digestive issues.
["A simple stool test to identify *H. pylori* infection, often used to diagnose stomach problems linked to this bacteria."]
Key facts at a glance
- LOINC
- 91861-5
- Short code
- C trach Ag Aspirate Ql IF
- Synonyms
- C trach Ag Aspirate Ql IF
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- if
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Matters
Helicobacter pylori is a bacteria that can live in your stomach and may cause inflammation, ulcers, or even long-term damage. This test helps doctors identify if you have an infection, which can guide treatment options like antibiotics or other therapies.
How the Test Works
Your stool sample is tested for specific proteins (antigens) produced by *H. pylori*. If the bacteria are present, these proteins will be detected, confirming an infection.
What to Expect Before the Test
No special preparation is needed. You may collect a stool sample at home or provide one during a doctor’s visit. The test is quick and painless, using a simple sample collection method.
What the Results Mean
A positive result means *H. pylori* is likely present in your stool. A negative result suggests no active infection at the time of testing. Follow-up testing or additional evaluation may be needed if symptoms persist.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
H. pylori stool antigen test
Frequently asked questions
This test is commonly used to diagnose *H. pylori* infection, which can cause chronic gastritis, peptic ulcers, or even stomach cancer in some cases. Early identification allows for targeted treatment to reduce risk and improve symptoms.
Can I eat or drink anything before the test? You can eat and drink normally, as no special preparation is required for this stool-based test.
Is there any risk or discomfort with this test? No, this test is completely painless. You simply provide a small stool sample, either at home or during a visit to your doctor.
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy