title: Current consensus on the diagnosis and treatment of H. pylori-associated gastroduodenal disease.
abstract: Helicobacter pylori (H. pylori) is a spiral shaped bacterium that resides in the stomach mucosa. Isolation of H. pylori from the stomach mucosa changed the erstwhile widely held belief that the stomach contains no bacteria and is actually sterile. Once H. pylori is safely ensconced in the mucus, it is able to neutralize the acid in the stomach by elaborating an enzyme called urease. Urease converts urea, of which there is an abundant supply in the stomach (derived from saliva and the gastric juice), into bicarbonate and ammonia, which are strong bases. These bases form a cloud of acid-neutralizing chemicals in the vicinity of the organisms, protecting them from the acid in the stomach. This urea hydrolysis reaction is utilized for the diagnosis of H. pylori infection in the urea breath test (UBT) and the rapid urease test (RUT). In Japan, both invasive tests, such as bacterial culture, histopathology and RUT, and non-invasive tests such as UBT and serology are conducted for the diagnosis of H. pylori infection. For confirming the results of eradication therapy, UBT is considered to be the most sensitive and specific. In order to treat H. pylori infection, a new one-week triple therapy regimen (lansoprazole or omeprazole + amoxicillin + clarithromycin) has been approved for use in patients with peptic ulcer disease in Japan. As for H. pylori eradication in the case of other diseases in which the bacterium has been implicated (e.g., chronic atrophic gastritis, gastric MALT lymphoma, gastric cancer, non-ulcer dyspepsia, chronic urticaria, idiopathic thrombocytopenic purpura (ITP)), further basic and clinical investigation is required.
authors.affiliation: Department of Internal Medicine, School of Medicine Keio University, Tokyo, Japan. hsuzuki@sc.itc.keio.ac.jp
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Suzuki
authors.forename: Tatsuhiro
authors.initials: T
authors.lastname: Masaoka
authors.forename: Sachiko
authors.initials: S
authors.lastname: Nomura
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Hoshino
authors.forename: Kumiko
authors.initials: K
authors.lastname: Kurabayashi
authors.forename: Yuriko
authors.initials: Y
authors.lastname: Minegishi
authors.forename: Masayuki
authors.initials: M
authors.lastname: Suzuki
authors.forename: Hiromasa
authors.initials: H
authors.lastname: Ishii
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000658:Amoxicillin / Q000627:therapeutic use; D000818:Animals; D017209:Apoptosis; D002624:Chemistry, Clinical / Q000379:methods; D017291:Clarithromycin / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D005753:Gastric Mucosa / Q000382:microbiology; D005767:Gastrointestinal Diseases / Q000382:microbiology*; D005849:Gerbillinae; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000628:therapy*; D016480:Helicobacter pylori / Q000472:pathogenicity*; D007564:Japan; D064747:Lansoprazole; D009853:Omeprazole / Q000031:analogs & derivatives* / Q000627:therapeutic use; D010437:Peptic Ulcer / Q000175:diagnosis* / Q000382:microbiology*; D014510:Urease / Q000378:metabolism
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D064747:Lansoprazole; D000658:Amoxicillin; D014510:Urease; D017291:Clarithromycin; D009853:Omeprazole