title: Short duration therapy for Helicobacter pylori in Western Australia: the impact of metronidazole resistance.
abstract: BACKGROUND
  Limited Australian data are available on either short duration therapy for Helicobacter pylori infection, or the impact of metronidazole resistance on the outcome of treatment.
  
  
  OBJECTIVE
  To compare the efficacy of two treatment regimens and determine the influence metronidazole resistance has on clearing H. pylori infection.
  
  
  METHODS
  Eighty patients with H. pylori infection proven at upper gastrointestinal endoscopy, none of whom had previously received therapy for H. pylori, were randomised to one week therapy with either bismuth subcitrate one tablet qid, tetracycline 500 mg qid and metronidazole 400 mg tds (BTM), or lansoprazole 30 mg bd, amoxycillin 500 mg qid and metronidazole 400 mg tds (LAM). Effectiveness of therapy was measured by C14-urea breath test at six weeks.
  
  
  RESULTS
  On an intention-to-treat basis, clearance of infection was achieved in 17 of 32 (53%; 95% CI: 35-71%) evaluable patients receiving BTM and 32 of 46 (70%, 54-82%) patients receiving LAM (p = 0.16). Metronidazole resistance was found in 32 of 65 (49%) patients in whom H. pylori was isolated by culture. On a per-protocol basis, of patients who had metronidazole sensitive strains of H. pylori 23 of 24 (96%) cleared infection after therapy with either BTM or LAM, compared with 14 of 24 (58%) who were metronidazole resistant (p = 0.004). Clarithromycin resistance was not found in 45 patients tested.
  
  
  CONCLUSIONS
  In Western Australia clearance rates of H. pylori infection, after one week of BTM or LAM, are lower than in other published series. The high incidence of metronidazole resistance is the main determinant of our relatively poor eradication rates.
authors.affiliation: Department of Gastroenterology, Royal Perth Hospital, Western Australia.
authors.forename: G M
authors.initials: GM
authors.lastname: Forbes
authors.forename: B J
authors.initials: BJ
authors.lastname: Collins
authors.forename: C A
authors.initials: CA
authors.lastname: McCullough
authors.forename: G W
authors.initials: GW
authors.lastname: Coombs
authors.forename: P D
authors.initials: PD
authors.lastname: Robins
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000293:Adolescent; D000328:Adult; D000368:Aged; D000658:Amoxicillin / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use*; D004352:Drug Resistance, Microbial; D004359:Drug Therapy, Combination; D005260:Female; D016481:Helicobacter Infections / Q000188:drug therapy* / Q000453:epidemiology; D016480:Helicobacter pylori / Q000187:drug effects*; D006801:Humans; D015994:Incidence; D064747:Lansoprazole; D008297:Male; D008795:Metronidazole / Q000494:pharmacology / Q000627:therapeutic use*; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009853:Omeprazole / Q000031:analogs & derivatives / Q000627:therapeutic use; D010406:Penicillins / Q000627:therapeutic use; D013752:Tetracycline / Q000627:therapeutic use; D014904:Western Australia / Q000453:epidemiology
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000900:Anti-Bacterial Agents; D010406:Penicillins; D064747:Lansoprazole; D008795:Metronidazole; D000658:Amoxicillin; D013752:Tetracycline; D009853:Omeprazole