gastrointestinal disorders
Helicobacter pylori Infection
Key Points
H. pyloriis a gram-negative organism that is highly adapted to an acid environment and often infects the stomach; incidence of infection increases with age—by age 60, about 50% of people are infected. Infection predisposes to gastric, prepyloric, and duodenal ulcers and increases risk of gastric adenocarcinoma and lymphoma. Make initial diagnosis with aureabreath test or stool antigen assay; if endoscopy is being done for other reasons, analyze biopsy samples using a rapid urease test or histologic staining. Give treatment to eradicate the organism in patients with complications (eg, ulcer, cancer); a typical regimen includes quadruple therapy in areas that have resistance rates toclarithromycinof > 15% or a proton pump inhibitor plus two antibiotics (eg,clarithromycinplus eitheramoxicillinormetronidazole). Confirm cure using aureabreath test, stool antigen test, or upper endoscopy. 