Stomach disease

Overview
Many stomach diseases are associated with infection. Historically, it was widely believed that the highly acidic environment of the stomach would keep the stomach immune from infection. However, a large number of studies have indicated that most cases of stomach ulcers, gastritis, and stomach cancer are caused by Helicobacter pylori infection. One of the ways it is able to survive in the stomach involves its urease enzymes which metabolize urea (which is normally secreted into the stomach) to ammonia and carbon dioxide which neutralizes gastric acid and thus prevents its digestion. In recent years, it has been discovered that other Helicobacter bacteria are also capable of colonizing the stomach and have been associated with gastritis.

Having too little or no gastric acid is known as hypochlorhydria or achlorhydria respectively and are conditions which can have negative health impacts. Having high levels of gastric acid is called hyperchlorhydria. Many people believe that hyperchlorhydria can cause stomach ulcers. However, recent research indicates that the gastric mucosa which secretes gastric acid is acid-resistant.

Conditions
Diseases of the stomach include:
 * Dyspepsia
 * Abdominal pain
 * Peptic ulcer
 * Achlorhydria
 * Hypochlorhydria
 * Linitis plastica
 * Zollinger-Ellison syndrome
 * Gastroparesis
 * GERD
 * Borborygmus