The H. pylori test detects whether you have an infection with the bacteria H. pylori – the main cause of stomach ulcers and peptic ulcer disease. There are four main methods to detect signs of this bacteria: a breath (urea) test, a stool test, a blood test, and an upper endoscopy. If the result is positive, The doctor will consider prescribing an appropriate antibiotic regimen to kill the bacteria., especially if you have symptoms or risk factors.

What is the H. pylori (Helicobacter pylori) test?

An H. pylori test shows if you have an infection with H. pylori bacteria. This is a type of bacteria that lives in the stomach and small intestine and damages the stomach lining over time, leading to inflammation, gastritis, or peptic ulcers.

If you have symptoms of these conditions, your doctor may recommend testing. You may also need to be retested after treatment to make sure the infection is gone. There are several types of H. pylori tests, and your doctor will choose the one that is best for you.

When should I test for H. pylori? Your doctor may order the test if you have signs of a stomach ulcer or gastritis, such as:

• Dull or burning pain in the upper or middle abdomen, especially when hungry or at night.
• Stomach pain relieved by eating or taking antacids.
• Bloating.
• Nausea or vomiting.

What are the H. pylori tests? There are four main ways to test for H. pylori infection:

• Breath test.
• Stool test.
• Blood test.
• Endoscopy and biopsy.

Below are details of each method:

H. pylori breath test (urea breath test) This is the most common test. You drink a solution containing urea, which the H. pylori bacteria break down into CO₂ gas. If the CO₂ level in your breath is high, it means you have an infection.

H. pylori stool test A stool antigen test (SAT) looks for signs of bacteria in your stool. Antigens are substances that help your immune system recognize bacteria. If they are found in your stool, it means that bacteria are present in your digestive tract.

H. pylori blood test A blood test that looks for antibodies to H. pylori. Antibodies are proteins your immune system makes to fight bacteria. They can remain in your blood even after the infection has cleared. Because antibodies can remain in your blood for months or years after the infection has cleared, Blood tests cannot distinguish between active and past infections.. Therefore, it not recommended for initial diagnosis or to assess treatment effectiveness.

Upper gastrointestinal endoscopy (EGD) This is the most accurate test, but it is more invasive. The doctor uses an endoscope with a camera to look inside and take tissue samples (biopsies) for testing. This method is chosen if other problems besides H. pylori need to be checked.

Test details

How to prepare for H. pylori testing? You will need to tell your doctor about all the medicines you are taking. Usually, you will be asked to:

• Stop Proton pump inhibitors (PPIs): at least 2 weeksbefore testing (breath, stool, endoscopy).
  • Stop Antibiotics and Bismuth: at least 4 weeksbefore testing.
  Note: Discontinuation of medication requires the consent and guidance of a physician.

You may need to fast for a short time before the test. Your doctor will give specific instructions depending on the type of test.

How does the testing process work? Depending on the type of test, the procedure will vary.

Breath test procedure

• Breathe into the first bag to measure the initial CO₂ level.
• Drink the urea solution, wait 15 minutes.
• Breathe into the second bag. If the CO₂ increases, you may be infected.

Stool testing process The doctor provides a container, you collect the stool sample at home according to the instructions and bring it back. Follow the instructions correctly to get an accurate test result.

Blood test procedure Take blood from a vein in the arm like a regular blood draw and send the sample to the lab.

Endoscopic procedure The procedure lasts about an hour and you will be given a light anesthetic to keep you comfortable. The doctor will insert an endoscope through your mouth into your stomach and small intestine, looking at it on a monitor and taking tissue samples if needed. After the test, you will need someone to take you home because of the anesthesia.

What happens after the test? You can go about your normal activities. For endoscopy, you should rest that day because of the anesthesia. A blood, stool, or tissue sample will be sent to a lab, and results will be available in a few days.

Results and follow-up

What is the result and what does it mean? A positive or negative result indicates the presence or absence of H. pylori infection.

What does a positive result mean? You are currently or have been infected with H. pylori. With positive breath, stool or endoscopy: active infection, need antibiotics. With positive blood: can be current or past, doctor will explain and guide further.

What does a negative result mean? No H. pylori infection. If symptoms persist, your doctor may do further testing to look for other causes.

When will I get the results? Usually 1-3 days. Ask your doctor before you go home how to get your results.

Frequently Asked Questions

What is the most accurate H. pylori test?
• Breath test and stool antigen test are considered as methods the most accurate and reliable to diagnose active infection, with the advantage of being non-invasive.
• Endoscopy: not only helps detect H. pylori through biopsy but also allows the doctor direct assessment of gastric mucosal condition and detect lesions such as inflammation, ulceration, or atrophy. This is the optimal choice when the patient has alarming symptoms or requires a comprehensive evaluation.
• Blood test: has high sensitivity but limitations as mentioned.

Your doctor will choose the best method based on your needs.