Gastritis is a condition in which the stomach lining—known as the mucosa—is inflamed. The stomach lining contains special cells that produce acid and enzymes, which help break down food for digestion, and mucus, which protects the stomach lining from acid. When the stomach lining is inflamed, it produces less acid, enzymes, and mucus.
Gastritis may be acute or chronic. Sudden, severe inflammation of the stomach lining is called acute gastritis. Inflammation that lasts for a long time is called chronic gastritis. If chronic gastritis is not treated, it may last for years or even a lifetime. Erosive gastritis is a type of gastritis that often does not cause significant inflammation but can wear away the stomach lining. Erosive gastritis can cause bleeding, erosions, or ulcers.
Helicobacter pylori (H. pylori) infection causes most cases of chronic nonerosive gastritis. H. pylori are bacteria that infect the stomach lining. H. pylori are primarily transmitted from person to person. In areas with poor sanitation, H. pylori may be transmitted through contaminated food or water.
In industrialized countries, 20 to 50 percent of the population may be infected with H. pylori. Rates of H. pylori infection are higher in areas with poor sanitation and higher population density. Infection rates may be higher than 80 percent in some developing countries.
Other causes of erosive and nonerosive gastritis include:
Many people with gastritis do not have any symptoms, but some people experience symptoms such as:
These symptoms are also called dyspepsia.
Erosive gastritis may cause ulcers or erosions in the stomach lining that can bleed. Signs of bleeding in the stomach include:
Chronic gastritis is a risk factor for peptic ulcer disease, gastric polyps, and benign and malignant gastric tumors. Some people with chronic H. pylori gastritis or autoimmune gastritis develop atrophic gastritis. Atrophic gastritis destroys the cells in the stomach lining that produce digestive acids and enzymes. Atrophic gastritis can lead to two types of cancer: gastric cancer and gastric mucosa-associated lymphoid tissue (MALT) lymphoma.
Medications that reduce the amount of acid in the stomach can relieve symptoms that may accompany gastritis and promote healing of the stomach lining. These medications include:
Depending on the cause of the gastritis, additional measures or treatments may be needed. For example, if gastritis is caused by prolonged use of NSAIDs, a doctor may advise a person to stop taking NSAIDs, reduce the dose of NSAIDs, or switch to another class of medications for pain. PPIs may be used to prevent stress gastritis in critically ill patients.
Treating H. pylori infections is important, even if a person is not experiencing symptoms from the infection. Untreated H. pylori gastritis may lead to cancer or the development of ulcers in the stomach or small intestine. The most common treatment is a triple therapy that combines a PPI and two antibiotics—usually amoxicillin and clarithromycin—to kill the bacteria. Treatment may also include bismuth subsalicylate (Pepto-Bismol) to help kill bacteria.