gastrointestinal disorders
Helicobacter pylori Infection
Introduction
Helicobacter pyloriis a common gastric pathogen that causes gastritis, peptic ulcer disease, gastric adenocarcinoma, and low-grade gastric lymphoma. Infection may be asymptomatic or result in varying degrees of dyspepsia. Diagnosis is byureabreath test, stool antigen test, and testing of endoscopic biopsy samples. Treatment is typically with a proton pump inhibitor plus two antibiotics and oftenbismuth subsalicylate. (See also Overview of Acid Secretion and H. pyloriis a spiral-shaped, gram-negative organism that has adapted to thrive in acid. In low- and middle-income countries, it commonly causes chronic infections and is usually acquired during childhood. In the United States, infection is less common among children but increases with age: by age 60, about 50% of people are infected. Infection is most common among Black, Hispanic, and Asian people. The organism has been cultured from stool, saliva, and dental plaque, which suggests oral-oral or fecal-oral transmission. Infections tend to cluster in families and in residents of custodial institutions. Nurses and gastroenterologists seem to be at high risk because bacteria can be transmitted by improperly disinfected endoscopes. 