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 Introduction to Gastritis and Peptic Ulcer Disease Gastritis and peptic ulcer disease involve damage to the lining of the stomach or duodenum (the first segment of the small intestine). These disorders are usually caused by Stomach acid (hydrochloric... read more .)
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 in the United States 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 infects the lining of the stomach and can also 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.
Virtually all people who have H. pylori infection have stomach inflammation (gastritis Gastritis Gastritis is inflammation of the stomach lining. The inflammation can be caused by many factors, including infection, stress resulting from severe illness, injury, certain drugs, and disorders... read more ), which may affect the entire stomach or only the lower part (antrum). Infection can sometimes lead to erosive gastritis Gastritis Gastritis is inflammation of the stomach lining. The inflammation can be caused by many factors, including infection, stress resulting from severe illness, injury, certain drugs, and disorders... read more and perhaps even a stomach (gastric) ulcer Peptic Ulcer Disease A peptic ulcer is a round or oval sore where the lining of the stomach or duodenum has been eaten away by stomach acid and digestive juices. Peptic ulcers can result from Helicobacter pylori... read more .
H. pylori contributes to ulcer formation by increasing acid production, interfering with the stomach's normal defenses against stomach acid, and producing toxins.
Long-term infection with H. pylori increases the risk of stomach cancer Stomach Cancer A Helicobacter pylori infection is a risk factor for stomach cancer. Vague abdominal discomfort, weight loss, and weakness are some typical symptoms. Diagnosis includes endoscopy and biopsy... read more .
Only 20% of people whose gastritis was caused by H. pylori infection develop symptoms or complications such as a peptic ulcer of the stomach or duodenum.
People who do develop symptoms resulting from H. pylori infection have those typical of gastritis, including indigestion Indigestion Indigestion is pain or discomfort in the upper abdomen. People may also describe the sensation as gassiness, a sense of fullness, or gnawing or burning. The sense of fullness may occur after... read more and pain or discomfort in the upper abdomen.
Ulcers caused by H. pylori infection cause symptoms similar to ulcers caused by other disorders, including pain in the upper abdomen.
H. pylori can be detected with tests that use breath or stool samples.
Sometimes doctors use a flexible viewing tube (endoscope) to do an upper endoscopy Endoscopy Endoscopy is an examination of internal structures using a flexible viewing tube (endoscope). Endoscopy can also be used to treat many disorders because doctors are able to pass instruments... read more to obtain a sample (biopsy) of the stomach lining. The sample can be tested for H. pylori by several methods.
The likelihood that a peptic ulcer caused by H. pylori infection will return during the course of 3 years is greater than 50% in people who have not been treated with antibiotics. This percentage decreases to less than 10% in people who have been treated with antibiotics. In addition, treatment of H. pylori infection may heal ulcers that have resisted previous treatment.
The most common treatments for H. pylori infection include a proton pump inhibitor Proton pump inhibitors Stomach acid plays a role in a number of disorders of the stomach, including peptic ulcer, gastritis, and gastroesophageal reflux disease (GERD). Although the amount of acid present in the stomach... read more to reduce stomach acid production, two antibiotics, and sometimes also bismuth subsalicylate to kill the infection. One of several proton pump inhibitors, lansoprazole, omeprazole, pantoprazole, rabeprazole, or esomeprazole, is given. These drugs may cause diarrhea, constipation, and headache. Several different antibiotics may be used, including amoxicillin, clarithromycin, metronidazole, and tetracycline. All of these antibiotics may alter taste and cause nausea, and amoxicillin, clarithromycin, and tetracycline may cause diarrhea. Bismuth subsalicylate may cause constipation and darkening of the tongue and stool.
Doctors typically confirm that treatment was successful by repeating breath or stool tests or endoscopy about 4 weeks after treatment is finished.
Treatment is repeated if H. pylori is not eradicated.