Tests for H pylori
Peptic ulcer disease - H pylori; PUD - H pyloriHelicobacter pylori (H pylori) is the bacteria (germ) responsible for most stomach (gastric) and duodenal ulcers and many cases of stomach inflammation (chronic gastritis).
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How the Test is Performed
There are several methods to test for H pylori infection.
Breath Test (Carbon Isotope-urea Breath Test, or UBT)
- Up to 2 weeks before the test, you need to stop taking antibiotics, bismuth medicines such as Pepto-Bismol, and proton pump inhibitors (PPIs).
- During the test, you swallow a special substance that has urea. Urea is a waste product the body produces as it breaks down protein. The urea used in the test has been made harmlessly radioactive.
- If H pylori are present, the bacteria convert the urea into carbon dioxide, which is detected and recorded in your exhaled breath after 10 minutes.
- This test can identify almost all people who have H pylori. It can also be used to check that the infection has been fully treated.
Blood Tests
- Blood tests are used to measure antibodies to H pylori. Antibodies are proteins made by the body's immune system when it detects harmful substances such as bacteria.
- Blood tests for H pylori can only tell if your body has H pylori antibodies. It cannot tell if you have a current infection or how long you have had it. This is because the test can be positive for years, even if the infection is cured. As a result, blood tests cannot be used to see if the infection has been cured after treatment.
Stool Test
- A stool test can detect traces of H pylori in the feces.
- This test can be used to diagnose the infection and confirm that it has been cured after treatment.
Biopsy
- A tissue sample, called a biopsy, is taken from the stomach lining. This is the most accurate way to tell if you have an H pylori infection.
- To remove the tissue sample, you have a procedure called esophagogastroduodenoscopy (EGD). The procedure is done in the hospital or outpatient center.
- Usually, a biopsy is done if EGD is needed for other reasons. Reasons include diagnosing the ulcer, treating bleeding, or making sure there is no cancer.
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Why the Test is Performed
Testing is most often done to diagnose H pylori infection:
- If you currently have a stomach or duodenal ulcer
- If you had a stomach or duodenal ulcer in the past, and were never tested for H pylori
- After treatment for H pylori infection, to make sure there are no more of these bacteria
Testing may also be done if you need to take long-term ibuprofen or other NSAID medicines. Your health care provider can tell you more.
The test may also be recommended for a condition called dyspepsia (indigestion). This is upper abdominal discomfort. Symptoms include a feeling of fullness or of heat, burning, or pain in the area between the navel and the lower part of the breastbone during or after eating. Testing for H pylori without EGD is most often done only when the discomfort is new, the person is younger than 55, and there are no other symptoms.
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Normal Results
Normal results mean there is no sign that you have an H pylori infection.
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What Abnormal Results Mean
Abnormal results mean that you have an H pylori infection. Your provider will discuss treatment with you.
References
Cover TL, Blaser MJ. Helicobacter pylori and other gastric Helicobacter species. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 217.
Siddiqi HA, Rabinowitz S, Axiotis CA. Laboratory diagnosis of gastrointestinal and pancreatic disorders. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 23.