title: Nonbismuth quadruple (concomitant) therapy: empirical and tailored efficacy versus standard triple therapy for clarithromycin-susceptible Helicobacter pylori and versus sequential therapy for clarithromycin-resistant strains.
abstract: BACKGROUND
  Using quadruple clarithromycin-containing regimens for Helicobacter pylori eradication is controversial with high rates of macrolide resistance.
  
  
  OBJECTIVE
  To evaluate antibiotic resistance rates and the efficacy of empirical and tailored nonbismuth quadruple (concomitant) therapy in a setting with cure rates <80% for triple and sequential therapies.
  
  
  METHODS
  209 consecutive naive H. pylori-positive patients without susceptibility testing were empirically treated with 10-day concomitant therapy (proton pump inhibitors (PPI), amoxicillin 1 g, clarithromycin 500 mg, and metronidazole 500 mg; all drugs b.i.d.). Simultaneously, 89 patients with positive H. pylori culture were randomized to receive triple versus concomitant therapy for clarithromycin-susceptible H. pylori, and sequential versus concomitant therapy for clarithromycin-resistant strains. Eradication was confirmed with ¹³C-urea breath test or histology 8 weeks after completion of treatment.
  
  
  RESULTS
  Per-protocol (PP) and intention-to-treat eradication rates after empirical concomitant therapy without susceptibility testing were 89% (95%CI:84-93%) and 87% (83-92%). Antibiotic resistance rates were: clarithromycin, 20%; metronidazole, 34%; and both clarithromycin and metronidazole, 10%. Regarding clarithromycin-susceptible H. pylori, concomitant therapy was significantly better than triple therapy by per protocol [92% (82-100%) vs 74% (58-91%), p = 0.05] and by intention to treat [92% (82-100%) vs 70% (57-90%), p = 0.02]. As for antibiotic-resistant strains, eradication rates for concomitant and sequential therapies were 100% (5/5) vs 75% (3/4), for clarithromycin-resistant/metronidazole-susceptible strains and 75% (3/4) vs 60% (3/5) for dual-resistant strains.
  
  
  CONCLUSIONS
  Empirical 10-day concomitant therapy achieves good eradication rates, close to 90%, in settings with multiresistant H. pylori strains. Tailored concomitant therapy is significantly superior to triple therapy for clarithromycin-susceptible H. pylori and at least as effective as sequential therapy for resistant strains.
authors: Department of Gastroenterology, Hospital San Pedro de Alcantara, Caceres, Spain. xavi_molina@hotmail.com
authors: Javier
authors: J
authors: Molina-Infante
authors: Carmen
authors: C
authors: Pazos-Pacheco
authors: Gema
authors: G
authors: Vinagre-Rodriguez
authors: Belen
authors: B
authors: Perez-Gallardo
authors: Carmen
authors: C
authors: Dueñas-Sadornil
authors: Moisés
authors: M
authors: Hernandez-Alonso
authors: Guadalupe
authors: G
authors: Gonzalez-Garcia
authors: Jose M
authors: JM
authors: Mateos-Rodriguez
authors: Miguel
authors: M
authors: Fernandez-Bermejo
authors: Javier P
authors: JP
authors: Gisbert
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000658:Amoxicillin / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D017291:Clarithromycin / Q000627:therapeutic use*; D024881:Drug Resistance, Bacterial; D004359:Drug Therapy, Combination; D005260:Female; D016481:Helicobacter Infections / Q000188:drug therapy* / Q000382:microbiology; D016480:Helicobacter pylori / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D008297:Male; D008795:Metronidazole / Q000627:therapeutic use*; D008875:Middle Aged; D054328:Proton Pump Inhibitors / Q000627:therapeutic use; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D054328:Proton Pump Inhibitors; D008795:Metronidazole; D000658:Amoxicillin; D017291:Clarithromycin