title: Helicobacter pylori eradication therapy.
abstract: Helicobacter pylori infection is the main cause of gastritis, gastroduodenal ulcers and gastric cancer. H. pylori eradication has been shown to have a prophylactic effect against gastric cancer. According to several international guidelines, the first-line therapy for treating H. pylori infection consists of a proton pump inhibitor (PPI) or ranitidine bismuth citrate, with any two antibiotics among amoxicillin, clarithromycin and metronidazole, given for 7-14 days. However, even with these recommended regimens, H. pylori eradication failure is still seen in more than 20% of patients. The failure rate for first-line therapy may be higher in actual clinical practice, owing to the indiscriminate use of antibiotics. The recommended second-line therapy is a quadruple regimen composed of tetracycline, metronidazole, a bismuth salt and a PPI. The combination of PPI-amoxicillin-levofloxacin is a good option as second-line therapy. In the case of failure of second-line therapy, the patients should be evaluated using a case-by-case approach. European guidelines recommend culture before the selection of a third-line treatment based on the microbial antibiotic sensitivity. H. pylori isolates after two eradication failures are often resistant to both metronidazole and clarithromycin. The alternative candidates for third-line therapy are quinolones, tetracycline, rifabutin and furazolidone; high-dose PPI/amoxicillin therapy might also be promising.
authors.affiliation: Division of Gastroenterology & Hepatology, Department of Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. hsuzuki@sc.itc.keio.ac.jp.
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Suzuki
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Nishizawa
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Hibi
mesh_terms: D000658:Amoxicillin / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D000897:Anti-Ulcer Agents / Q000627:therapeutic use*; D001729:Bismuth / Q000627:therapeutic use; D017291:Clarithromycin / Q000627:therapeutic use; D024881:Drug Resistance, Bacterial; D017408:Guidelines as Topic; D016481:Helicobacter Infections / Q000188:drug therapy*; D016480:Helicobacter pylori / Q000187:drug effects*; D006801:Humans; D064704:Levofloxacin; D008795:Metronidazole / Q000627:therapeutic use; D015242:Ofloxacin / Q000627:therapeutic use; D054328:Proton Pump Inhibitors / Q000627:therapeutic use*; D011899:Ranitidine / Q000031:analogs & derivatives / Q000627:therapeutic use; D013752:Tetracycline / Q000627:therapeutic use; D017211:Treatment Failure; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D000897:Anti-Ulcer Agents; D054328:Proton Pump Inhibitors; D008795:Metronidazole; D064704:Levofloxacin; C073340:ranitidine bismuth citrate; D000658:Amoxicillin; D011899:Ranitidine; D015242:Ofloxacin; D013752:Tetracycline; D017291:Clarithromycin; D001729:Bismuth