A type of bacteria found in the stomach that can cause ulcers or other symptoms.

What is H. pylori?

Helicobacter pylori, also known as H. pylori, is a bacteria that is commonly found in the stomach. It is present in approximately one-half of the world's population. H. pylori infections are the most common cause of stomach ulcers, and a cause of inflammation of the stomach lining.  Over time this chronic inflammation may contribute to abnormal cell growth and contribute to stomach cancer. 


What causes H. pylori?

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. The stomach is generally a very hostile environment for many bacteria, but H. pylori is especially well-adapted for survival in the stomach. H. pylori can weaken the protective mucous coating of the stomach and first part of the small intestine (duodenum), which allows acid to get through to the sensitive lining beneath. Both the acid from the stomach and the bacteria can irritate the lining and cause a sore, or ulcer.


What are the symptoms of H. pylori?

The presence of H. pylori does not always cause symptoms; however, if a sore or ulcer is present you may experience abdominal pain, nausea, vomiting, bloody or black tarry stools, bloating or change in appetite or weight loss.


How is H. pylori diagnosed?

Your doctor will review your history and perform a physical examination as well as order a series of tests to help determine the cause of your abdominal pain. These tests may include:

  • Breath test: H. pylori produces a naturally occurring chemical called urea that can be detected with a breath test.
  • Stool antigen tests: A stool sample is sent to the lab to detect foreign proteins (antigens) that are present with an H. pylori infection.
  • Endoscopy: Your doctor may perform an upper endoscopy to view your upper digestive tract and take biopsies. With this procedure, a long flexible tube with a tiny camera is passed through your esophagus, stomach and the first part of your small intestine. Biopsies (microscopic tissue specimens) of the stomach can be obtained to look for H. pylori bacteria under the microscope.


How is H. pylori treated?

Your doctor will typically prescribe a combination of  medications taken together to treat the bacteria over the course of 2 weeks. Examples include:

  • Antibiotics: metronidazole, tetracycline, clarithromycin, amoxicillin
  • Proton pump inhibitors: omeprazole, lansoprazole, rabeprazole, esomeprazole, pantoprozole
  • Bismuth subsalicylate


What happens after H. pylori is treated?

Your doctor will often follow up with you after the infection is treated and test that the bacteria has gone away.  This may include repeat breath test or stool test. Most of the time H. pylori is cured with one treatment; occasionally it is not cured and you might need more medication.


When to seek medical advice:

Contact your doctor or go to the emergency room right away if you experience bloody or black stools, have bloody vomit that looks like coffee grounds, or red blood colored, or if you experience severe, persistent upper abdominal pain.