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Helicobacter pylori

7-minute read

Key facts

  • Helicobacter pylori (H. pylori) is a type of bacterium that can live in the lining of the stomach.
  • H.pylori can cause stomach inflammation (gastritis) and more serious conditions such as stomach ulcers and stomach cancer.
  • Many Australians have it, but don't have any symptoms.
  • Treating and removing H.pylori infection heals most peptic ulcers and reduces the risk of stomach cancer.


What is Helicobacter pylori?

Helicobacter pylori (H. pylori) is a bacterium that lives in the lining of the stomach. More than half of the world’s population is infected with it and 15 per cent of Australians are estimated to have it. The prevalence is much higher among Indigenous Australians and in developing countries.

H. pylori causes inflammation of the stomach lining (known as gastritis) and increased production of gastric acid. Infection with H. pylori is a major cause of peptic ulcers (gastric ulcers and duodenal ulcers) and is linked to some stomach cancers.

How is Helicobacter pylori transmitted?

It's not fully understood how people get infected with H. pylori. Most people become infected as children, but you can also be infected as an adult.

H. pylori is mostly transmitted from person to person within families, or sometimes in day care. It may be spread if infected people don’t wash their hands after a bowel movement, or through kissing and other close contact. With improvements in basic hygiene there has been a decrease in H. pylori in the developed world.

Once Helicobacter pylori is living in the stomach lining, it will be there for life, unless it is treated with specific antibiotics.

What conditions does Helicobacter pylori cause?

Nearly everyone who is infected with H. pylori develops gastritis (inflammation of the lining of the stomach) but they may not show any symptoms. When there are symptoms it is known as H. pylori-associated dyspepsia.

If you are infected with H. pylori, you are more likely than other people to develop ulcers in the stomach or duodenum (the first part of the small intestine).

It also increases the risk of cancer of stomach (gastric) cancer.

Fortunately, treating and removing H. pylori infection heals most peptic ulcers and reduces the risk of stomach cancer.

H. pylori infection causes most cases of an uncommon disease called gastric mucosa-associated lymphoid tissue (MALT) lymphoma – a slow-growing lymphoma that starts in the stomach. If the H. pylori infection is treated successfully when the lymphoma is low grade, there is often regression of the lymphoma, meaning that it gets smaller, and may even be cured.

What are the symptoms of Helicobacter pylori infection?

Most people with H. pylori infection don’t have any symptoms. If symptoms are present they may include:

How is Helicobacter pylori diagnosed?

There are several ways H. pylori can be detected. Your doctor will request the right tests for you, which might include:

A breath test involves drinking water and swallowing a capsule containing a small amount of radioactive urea. H. pylori breaks down urea in the stomach to produce carbon dioxide. After about 10 minutes you will be asked to blow into a balloon that catches your breath for analysis by the laboratory. The amount of radioactivity in the capsule is very small – less than the background radiation you would be exposed to during a normal day.

A blood test looks for antibodies to H. pylori, but is not the first choice of test as a person may still have antibodies after an infection has been treated and the bacteria eradicated.

A stool sample detects proteins from H. pylori in your stool indicating an infection.

An endoscopy (where a thin tube is inserted down your oesophagus) to examine your stomach and do a biopsy would only be suggested in certain circumstances, such as when a person has a strong family history of gastric cancer or has particular symptoms.

Your doctor can advise whether you would benefit from testing and treatment, based on your medical history and background.

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How is Helicobacter pylori treated?

If you are diagnosed with H.pylori after having a test, you will be offered eradication therapy – a combination of medicines designed to kill the H. pylori bacteria. Eradication therapy is a mix of antibiotics and acid-suppressing medicine, known as triple therapy. The antibiotics kill the H. pylori bacteria, and the acid-suppressing medicine reduces stomach acid, so any ulcers can heal.

After you have taken the eradication therapy for the prescribed time (usually a week), you will likely be offered a breath test to make sure the treatment has worked.

If you were diagnosed with a stomach ulcer caused by H. pylori, then eradicating H. pylori will allow your existing ulcers to heal and help prevent more ulcers from developing.

Once H.pylori has been successfully eradicated, your risk of being infected again is very low.

It’s important to take the eradication therapy medicines as directed by your doctor and to finish the full course, otherwise your chance of clearing the infection will be reduced.

In a small number of people, the first attempt at eradication therapy does not work, due to antibiotic resistance. In this case, a person may need to see a Gastroenterologist for medicines tailored specifically for them.

Can Helicobacter pylori be prevented?

Most people who have H. pylori are infected in early childhood, but there is still limited evidence about what strategies would help prevent transmission of H. pylori.

Within a population, high density living, lack of sanitation and low hygiene are reported to increase the risk of being infected with H. pylori.

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