Helicobacter pylori (H. pylori) infection occurs when H. pylori bacteria infect your stomach. This usually happens during childhood. A common cause of peptic ulcers, H. pylori infection may be present in more than half the people in the world.
Most people don't realize they have H. pylori infection, because they never get sick from it. If you develop signs and symptoms of a peptic ulcer, your doctor will probably test you for H. pylori infection. If you have H. pylori infection, it can be treated with antibiotics.
Most people with H. pylori infection will never have any signs or symptoms. It's not clear why this is, but some people may be born with more resistance to the harmful effects of H. pylori.
When signs or symptoms do occur with H. pylori infection, they may include:
- An ache or burning pain in your abdomen
- Abdominal pain that's worse when your stomach is empty
- Loss of appetite
- Frequent burping
- Unintentional weight loss
When to see a doctor
Make an appointment with your doctor if you notice any persistent signs and symptoms that worry you. Seek immediate medical help if you experience:
- Severe or persistent abdominal pain
- Difficulty swallowing
- Bloody or black tarry stools
- Bloody or black vomit or vomit that looks like coffee grounds
The exact way H. pylori infects someone is still unknown. H. pylori bacteria may be passed from person to person through direct contact with saliva, vomit or fecal matter. H. pylori may also be spread through contaminated food or water.
H. pylori infection is often acquired in childhood. Risk factors for H. pylori infection are related to living conditions in your childhood, such as:
- Living in crowded conditions. You have a greater risk of H. pylori infection if you live in a home with many other people.
- Living without a reliable supply of clean water. Having a reliable supply of clean, running water helps reduce the risk of H. pylori.
- Living in a developing country. People living in developing countries, where crowded and unsanitary living conditions may be more common, have a higher risk of H. pylori infection.
- Living with someone who has an H. pylori infection. If someone you live with has H. pylori infection, you're more likely to also have H. pylori infection.
Complications associated with H. pylori infection include:
- Ulcers. H. pylori can damage the protective lining of your stomach and small intestine. This can allow stomach acid to create an open sore (ulcer). About 10% of people with H. pylori will develop an ulcer.
- Inflammation of the stomach lining. H. pylori infection can irritate your stomach, causing inflammation (gastritis).
- Stomach cancer. H. pylori infection is a strong risk factor for certain types of stomach cancer.
In areas of the world where H. pylori infection and its complications are common, doctors sometimes test healthy people for H. pylori. Whether there is a benefit to testing for H. pylori infection when you have no signs or symptoms of infection is controversial among doctors.
If you're concerned about H. pylori infection or think you may have a high risk of stomach cancer, talk to your doctor. Together you can decide whether you may benefit from H. pylori screening.