Antimicrobial susceptibility testing before first-line treatment for Helicobacter pylori infection in patients with dual or triple antibiotic resistance.

AIM: To evaluate the efficacy of antimicrobial susceptibility-guided therapy before first-line treatment for infection in patients with dual or triple antibiotic resistance. METHODS: A total of 1034 patients infected by Helicobacter pylori (H. pylori) during 2013-2014 were tested for antimicrobial susceptibility. 157 of 1034 (15%) patients showed resistance to two (127/1034; 12%) and to three (30/1034; 3%) antibiotics. Sixty-eight patients with dual H. pylori-resistance (clarithromycin, metronidazole or levofloxacin) were treated for 10 d with triple therapies: OAL (omeprazole 20 mg b.i.d., amoxicillin 1 g b.i.d., and levofloxacin 500 mg b.i.d.) 43 cases, OAM (omeprazole 20 mg b.i.d., amoxicillin 1 g b.i.d., and metronidazole 500 mg b.i.d.) 12 cases and OAC (omeprazole 20 mg b.id., amoxicillin 1 g b.i.d., and clarithromycin 500 mg b.i.d.) 13 cases based on the antimicrobial susceptibility testing. Twelve patients showed triple H. pylori-resistance (clarithromycin, metronidazole and levofloxacin) and received for 10 d triple therapy with OAR (omeprazole 20 mg b.id., amoxicillin 1 g b.i.d., and rifabutin 150 mg b.i.d.). Eradication was confirmed by 13C-urea breath test. Adverse effects and compliance were assessed by a questionnaire. RESULTS: Intention-to-treat eradication rates were: OAL (97.6%), OAM (91.6%), OAC (92.3%) and OAR (58.3%). Cure rate was significantly higher in naïve patients treated with OAR-10 compared to patients who had two or three previous treatment failures (83% vs 33%). Adverse events rates for OAL, OAM, OAC and OAR were 22%, 25%, 23% and 17%, respectively, all of them mild-moderate. CONCLUSION: Antimicrobial susceptibility-guided triple therapies during 10 d for first-line treatment leads to an eradication rate superior to 90% in patients with dual antibiotic H. pylori resistance.

Clarithromycin for first-line treatment of Helicobacter pylori infection after culture in high-resistance regions.

OBJECTIVE: Resistance to antibiotics is the major cause of treatment failure of Helicobacter pylori (HP) infection. The culture-guided triple therapy (chosen on the basis of a preliminary in-vitro susceptibility test) might help to increase treatment success in high antibiotic resistance regions. The aim of this study was to evaluate the effectiveness of treatment with clarithromycin in patients with clarithromycin-sensitive culture compared with patients treated empirically. METHODS: In this prospective and controlled trial, 111 naive HP-positive patients were randomized to receive standard triple therapy omeprazole (20 mg twice daily), amoxicillin (1 g twice daily), and clarithromycin (500 mg twice daily) for 10 days (OAC) after antimicrobial susceptibility testing if there was no resistance to clarithromycin (ClariS) or empirical 10-day OAC for first-line therapy of HP (ClariNA). Eradication was confirmed using the C-labelled urea breath test 6 weeks after therapy. Our primary outcome was HP eradication. Treatment adherence and adverse effects were recorded. RESULTS: The effectiveness of eradication by protocol with 10-day OAC therapy in the ClariS was 94% [95% confidence interval (CI): 0.83-0.98], which was 22% higher than ClariNA 72% (95% CI: 0.58-0.85; P=0.006). The odds ratio of eradication in ClariS was 1.30 (95% CI: 1.10-1.60; P<0.05 by logistic regression) and the number needed to treat was 5 (95% CI: 3-13). We found no significant difference in the occurrence of adverse effects or in compliance between the two groups. CONCLUSION: The eradication rate was significantly higher with clarithromycin-based triple therapy for patients with clarithromycin-susceptible HP isolates compared with those for whom no information on the corresponding susceptibility was available (ClinicalTrials.gov number NCT01486082).