Helicobacter pylori (H. pylori) Tests
H. pylori tests are used to detect a common bacterial infection in the stomach that can cause digestive issues, gastritis, and peptic ulcers.
What are Helicobacter pylori (H. pylori) tests?
Helicobacter pylori (H. pylori) is a common type of bacteria that infects the lining of the stomach and the first part of the small intestine. While most people never have symptoms, the bacteria can cause digestive problems, including peptic ulcers (sores in the stomach or small intestine) and gastritis (inflammation of the stomach lining). If left untreated, it can increase the risk of stomach cancer.
Other names: H. pylori stool antigen, H. pylori breath tests, urea breath test, rapid urease test (RUT), H. pylori culture
Why do I need an H. pylori test?
You may need testing if you have symptoms of gastritis or an ulcer, which include:
- Pain in your upper abdomen
- Bloating
- Feeling full too soon while eating
- Nausea and vomiting
- Burping or belching
- Loss of appetite or weight loss
Seek medical help immediately if you experience: black or tarry stool, red blood in vomit, sudden or severe belly pain, dizziness, fainting, or a rapid pulse.
Testing Methods
Breath Test
Also called a urea breath test, this involves breathing into a container, swallowing a pill or liquid containing urea, and then providing a second breath sample. If H. pylori is present, the bacteria change the urea into carbon dioxide, which is detected in the second breath sample.
Stool Tests
- Antigen tests: Check for proteins (antigens) from H. pylori.
- PCR tests: Check for genetic material from H. pylori.
Endoscopy
If other tests are inconclusive, a provider may perform an endoscopy. A thin tube with a camera is inserted through the mouth to examine the stomach and small intestine. A biopsy (tissue sample) may be taken for lab testing.
Preparation and Risks
You may need to stop taking certain medicines for two weeks to a month before testing. For an endoscopy, you will likely need to fast for several hours. There is no known risk to breath or stool tests; endoscopy carries a very small risk of a tear in the intestine or minor bleeding from a biopsy.
What do the results mean?
- Negative (normal): You likely do not have an H. pylori infection.
- Positive: You have an infection. Your provider will typically prescribe antibiotics and other medicines to heal your stomach. Repeat testing may be required after treatment to ensure the bacteria are gone.
Blood tests for H. pylori are not commonly used for diagnosis because they cannot distinguish between an active infection and a past one.