H. Pylori Infection

H. pylori is a bacteria that can cause peptic ulcer disease and gastritis. It mostly occurs in children. Only 20% of those infected have symptoms. Symptoms include dull or burning stomach pain, unplanned weight loss and bloody vomit. H-pylori-caused ulcers are commonly treated with combinations of antibiotics and proton pump inhibitors.


What is an H. pylori infection?

H. pylori (Helicobacter pylori) are bacteria that can cause an infection in the stomach or duodenum (first part of the small intestine). It’s the most common cause of peptic ulcer disease. H. pylori can also inflame and irritate the stomach lining (gastritis). Untreated, long-term H. pylori infection can lead to stomach cancer (rarely).


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Who gets H. pylori infections?

H. pylori bacteria are present in some 50% to 75% of the world’s population. It does not cause illness in most people. H. pylori infection mostly occurs in children. It’s more common in developing countries. In the U.S., H. pylori bacteria are found in about 5% of children under the age of 10. Infection is most likely to occur in children who live in crowded conditions and areas with poor sanitation.

Can H. pylori spread from person to person?

Yes, H. pylori can spread from person to person. H. pylori are found in saliva, plaque on teeth and poop. Infection can be spread through kissing and by transferring the bacteria from the hands of those who have not thoroughly washed them after a bowel movement.

Scientists think H. pylori also might be spread through H. pylori-contaminated water and food.


What’s the association between H. pylori infection and stomach cancer?

If you have an H. pylori infection, you have an increased risk for stomach cancer later in life. If you have a strong family history of stomach cancer and other cancer risk factors, even though you may not have symptoms of a stomach ulcer, your healthcare provider may recommend being tested for H. pylori antibodies. In addition to screening and treatment, your provider may suggest some lifestyle changes, such as including more fruits, vegetables and fiber in your diet. Regular checkups with your provider and following their recommendations can reduce your cancer risk.

Symptoms and Causes

How does H. pylori infection cause damage?

H. pylori multiply in the mucus layer of the stomach lining and duodenum. The bacteria secrete an enzyme called urease that converts urea to ammonia. This ammonia protects the bacteria from stomach acid. As H. pylori multiply, it eats into stomach tissue, which leads to gastritis and/or gastric ulcer.


What are the symptoms of H. pylori infection?

Most children with H. pylori infection don’t have symptoms. Only about 20% do.

Symptoms and signs, if present, are those that arise from gastritis or peptic ulcer and include:

  • Dull or burning pain in your stomach (more often a few hours after eating and at night). Your pain may last minutes to hours and may come and go over several days to weeks.
  • Unplanned weight loss.
  • Bloating.
  • Nausea and vomiting (bloody vomit).
  • Indigestion (dyspepsia).
  • Burping.
  • Loss of appetite.
  • Dark stools (from blood in your stool).

Diagnosis and Tests

How is H. pylori infection diagnosed?

If your healthcare provider suspects H. pylori bacteria may be causing a stomach ulcer, they may order one or more of the following tests:

  • A breath test: In this test, you exhale into a bag before and after drinking a solution. The test measures the amount of carbon dioxide released in your breath before and after drinking the solution. A higher level after drinking the solution means H. pylori are present.
  • A stool test: This test looks for evidence of H. pylori in a stool sample.
  • Upper endoscopy: A flexible tube is inserted down the throat into the stomach. A small tissue sample from the stomach or intestine lining is taken for testing for the presence of H. pylori.

Management and Treatment

How is H. pylori treated?

If you don’t have symptoms, you don’t need to be treated. If you've been diagnosed with H. pylori, avoid taking nonsteroidal anti-inflammatory drugs. These drugs can increase your risk of developing an ulcer.

H. pylori-caused ulcers are treated with a combination of antibiotics and an acid-reducing proton pump inhibitor.

  • Antibiotics: Usually two antibiotics are prescribed. Among the common choices are amoxicillin, clarithromycin (Biaxin®), metronidazole (Flagyl®) and tetracycline.
  • Proton pump inhibitor: Commonly used proton pump inhibitors include lansoprazole (Prevacid®), omeprazole (Prilosec®), pantoprazole (Protonix®), rabeprazole (Aciphex®) or esomeprazole (Nexium®).
  • Bismuth subsalicylate: Sometimes this drug (eg, Pepto-Bismol®) is added to the antibiotics plus proton pump inhibitor combinations mentioned above. This drug protects the stomach lining.

Combination treatment is usually taken for 14 days.

One newer medication, Talicia®, combines two antibiotics (rifabutin and amoxicillin) with a proton pump inhibitor (omeprazole) into a single capsule.


Can H. pylori infection be prevented?

You can lower your risk of H. pylori infection if you:

  • Drink clean water and use clean water during food preparation. (This is especially important if you live in areas of the world known to have a contaminated water supply.)
  • Wash your hands thoroughly (20 seconds) with soap and water before eating and after using the bathroom.

Is there a vaccine to prevent H. pylori infection?

Not yet, but there are promising results from a late-stage clinical trial. In this trial, children given the vaccine were protected against H. pylori infection for up to three years.

Outlook / Prognosis

What’s my child’s prognosis (outcome) if they’ve been diagnosed with an H. pylori infection?

If your child follows the treatment plan and takes all medication to its completion, the chance that an infection would return within three years is less than 10%. In addition, treatment may heal stomach ulcers. It can takes weeks to months for symptoms to completely go away.

How will I know if the H. pylori infection is healed?

Your healthcare provider will repeat a breath and/or stool test after waiting at least two weeks after proton pump inhibitor treatment has finished and four weeks after completing antibiotic treatment.

Medically Reviewed

Last reviewed on 03/19/2021.

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