title: Metronidazole containing quadruple therapy for infection with metronidazole resistant Helicobacter pylori: a prospective study.
abstract: BACKGROUND
  Metronidazole remains a key component of H. pylori infection therapy. It has been suggested that despite resistance, metronidazole may be effective when given at high dose with bismuth, tetracycline, and a proton pump inhibitor (quadruple therapy).
  
  
  OBJECTIVE
  To prospectively evaluate metronidazole quadruple therapy for treatment of metronidazole resistant H. pylori infection in the United States.
  
  
  METHODS
  Patients infected with metronidazole resistant H. pylori were prospectively prescribed 14 days of quadruple therapy consisting of metronidazole 500 mg t.d.s., tetracycline 500 mg q.d.s., two bismuth subsalicylate tablets q.d.s., and omeprazole 20 mg o.d.
  
  
  RESULTS
  A total of 26 patients were entered into the study; 22 for their first treatment and four as re-treatment for failed therapy. Of the 26 patients, 24 were cured (cure rate 92%; 95% CI: 78-99%). Both treatment failures reported full compliance to 14 days of therapy. Side-effects were common and resulted in premature discontinuation of therapy in 31%. Premature discontinuation did not reduce the cure rate.
  
  
  CONCLUSIONS
  Quadruple metronidazole combination therapy is effective despite the presence of metronidazole resistance and should be considered as either first line therapy or for failures of twice-a-day combination therapies.
authors.affiliation: Departments of Medicine, Paediatrics, Pathology, Molecular Virology and Microbiology, The VA Medical Center, Houston, Baylor College of Medicine, Houston, Texas 77030, USA. dgraham@bcm.tmc.edu
authors.forename: D Y
authors.initials: DY
authors.lastname: Graham
authors.forename: M S
authors.initials: MS
authors.lastname: Osato
authors.forename: J
authors.initials: J
authors.lastname: Hoffman
authors.forename: A R
authors.initials: AR
authors.lastname: Opekun
authors.forename: S Y
authors.initials: SY
authors.lastname: Anderson
authors.forename: D H
authors.initials: DH
authors.lastname: Kwon
authors.forename: H M
authors.initials: HM
authors.lastname: El-Zimaity
mesh_terms: D000368:Aged; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D000897:Anti-Ulcer Agents / Q000008:administration & dosage; D001729:Bismuth; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004351:Drug Resistance; D004359:Drug Therapy, Combination; D005260:Female; D016481:Helicobacter Infections / Q000188:drug therapy*; D016480:Helicobacter pylori / Q000187:drug effects; D006801:Humans; D008297:Male; D008795:Metronidazole / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D009853:Omeprazole / Q000008:administration & dosage; D009942:Organometallic Compounds; D010349:Patient Compliance; D011446:Prospective Studies; D012459:Salicylates; D013752:Tetracycline / Q000008:administration & dosage; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D000897:Anti-Ulcer Agents; D009942:Organometallic Compounds; D012459:Salicylates; D008795:Metronidazole; C015715:bismuth subsalicylate; D013752:Tetracycline; D009853:Omeprazole; D001729:Bismuth