Diagnosis and Treatment of Helicobacter pylori.

Helicobacter pylori infection remains a ubiquitous infection, especially in populations with poor socioeconomic conditions. Severe clinical outcomes of chronic infection include peptic ulcer disease and gastric cancer. Consensus meetings have developed guidelines for diagnosis, treatment, and management of H. pylori infection and related disorders in various populations. Clear benefits are obtained for H. pylori eradication in peptic ulcer disease and gastric mucosa-associated lymphoid tissue lymphoma. Most authorities agree that first-degree relatives of gastric cancer patients should undergo testing for H. pylori infection. H. pylori eradication in dyspepsia remains controversial. Global investigations continue to identify specific host and bacterial factors that are responsible for H. pylori-related inflammatory processes and development of clinical disease. Effective eradication regimens have been identified. The proton pump inhibitor (PPI)-based triple therapies are considered first-line therapy because of high patient compliance and good eradication rates. "Quadruple therapy" with bismuth-metronidazole-tetracycline plus a PPI is another first-line therapy with a similar eradication rate. This therapy is preferred in patients with penicillin allergy or prior exposure to clarithromycin. Rescue regimens are being developed because of rising antimicrobial resistance to metronidazole and clarithromycin in H. pylori strains. Emerging rescue combination therapies include furazolidone, rifabutin, and quinolones. These combination regimens are still preliminary and should be reserved for patients who have failed first-line therapies. Vaccine development remains elusive.