Helicobacter Pylori (H. Pylori): About This Test

What is it?

Helicobacter pylori (H. pylori) tests are used to check for this infection in the stomach and upper part of the small intestine. H. pylori can cause peptic ulcers. But most people with this type of bacteria in their digestive systems do not get ulcers.

Several tests may be used to check for an H. pylori infection.

• Urea breath test. It tests your breath to see if you have H. pylori bacteria in your stomach.
• Stool antigen test. This test looks for substances in your stool that trigger the immune system to fight an H. pylori infection. (These substances are called H. pylori antigens.)
• Stomach biopsy. A small tissue sample (biopsy) is taken from the lining of your stomach and small intestine. The sample is checked for H. pylori.
• Blood antibody test. This test is occasionally done to check to see if your body has made antibodies to fight H. pylori infection. This test is not as accurate as the other tests.

Why is this test done?

H. pylori tests are done to:

• Find out if an infection with H. pylori bacteria may be causing an ulcer or irritation of the stomach lining (gastritis).
• Find out if treatment for the infection worked.

How do you prepare for the test?

Blood antibody test

You do not need to do anything before you have this test.

Urea breath test, stool antigen test, or stomach biopsy

Medicines may change the results of these tests. Be sure to tell your doctor about ALL the medicines, vitamins, supplements, and herbal remedies you take. Your doctor may advise you to stop taking some of them.

• Do not take antibiotics or medicines containing bismuth (such as Pepto-Bismol) for 1 month before the test.
• Do not take proton pump inhibitors for 2 weeks before the test.

Urea breath test or stomach biopsy

You will be asked to not eat or drink anything for a certain amount of time before your breath test or stomach biopsy. Follow your doctor's instructions about how long you need to avoid eating and drinking before the test. If you are going to have a stomach biopsy, your doctor will give you instructions on how to prepare.

Many medicines may change the results of these tests.

• Do not take antibiotics or medicines containing bismuth (such as Pepto-Bismol) for 1 month before the test.
• Do not take proton pump inhibitors or H2 blockers for 2 weeks before the test.

How is the test done?

Blood antibody test

A health professional uses a needle to take a blood sample, usually from the arm.

Urea breath test

A breath sample is collected when you blow into a balloon or blow bubbles into a bottle of liquid. The health professional will:

• Collect a sample of your breath before the test starts.
• Give you a pill, a liquid, or some water to swallow that contains a special substance called urea.
• Collect more samples of your breath. The samples will be tested to see if they contain carbon dioxide, which is formed when H. pylori comes into contact with the urea.

Stool antigen test

For this test, you may be asked to collect the stool sample at home. To collect the sample, you need to:

• Put on gloves before handling your stool. Stool can contain germs that spread infection.
• Urinate before you collect the stool. Then pass stool into a dry container. Either solid or liquid stools can be collected. Be careful not to get urine or toilet tissue in with the stool sample.
• Replace the container cap. Label the container with your name, your doctor's name, and the date the sample was collected.
• Wash your hands well after you collect the sample and take off your gloves.
• Take the sealed container to your doctor's office or to the lab as soon as you can.

Sometimes a stool sample is collected during the exam using a rectal swab. The swab is inserted into the rectum, rotated gently, and then pulled out. It is placed in a clean, dry container and sent to the lab right away.

Stomach biopsy

A procedure called endoscopy is used to collect samples of tissue from the stomach and the first part of the small intestine. The tissue samples are tested in a lab to see if they contain H. pylori.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and contact your doctor if you are having problems. It's also a good idea to keep a list of the medicines you take. Ask your doctor when you can expect to have your test results.