Helicobacter pylori infection

[Dave Paprocki]

Helicobacter pylori (H. pylori) infection is a bacterial infection that causes stomach inflammation (gastritis), peptic ulcer disease, and certain types of stomach cancer.

The infection is caused by a type of bacteria called Helicobacter pylori (H. pylori).
When symptoms of H. pylori infection do occur, they include indigestion and pain or discomfort in the upper abdomen.
Doctors often base the diagnosis on the results of a breath test and an examination of the stomach using a flexible viewing tube (upper endoscopy).
Treatment is with antibiotics and a proton pump inhibitor.

(See also Introduction to Gastritis and Peptic Ulcer Disease.)
Infection with Helicobacter pylori is the most common cause of gastritis and peptic ulcer disease worldwide. Infection is very common and increases with age. By age 60, about 50% of people are infected. However, recent studies show fewer young people are becoming infected with H. pylori. Infection is most common among blacks, Hispanics, and Asians.
H. pylori can be found in stool, saliva, and plaque on the teeth. H. pylori can be transmitted from person to person, especially if people who are infected do not thoroughly wash their hands after a bowel movement. Because people may also spread the bacteria through kissing or other close contact, infections tend to cluster in families and among people who live in nursing homes and other supervised facilities.
H. pylori bacteria grow in the protective mucus layer of the stomach lining, where they are less exposed to the highly acidic juices produced by the stomach. Additionally, H. pylori produces ammonia, which helps protect it from stomach acid and enables it to disrupt and penetrate the mucus layer.