The efficacy of a 14-day modified quadruple therapy containing amoxicillin, tetracycline and high dose metronidazole and proton-pump inhibitors as an empirical third line helicobacter pylori eradication treatment in Taiwan

The antibiotics resistances to amoxicilln, tetracycline was low in Taiwan even after multiple H. pylori treatment failures and high dose metronidazole could overcome antibiotics resistance. In real world practice, susceptibility-guided treatments are not widely available. Therefore, we assessed the efficacy of 14-day modified quadruple therapy containing amoxicillin, tetracycline and high dose metronidazole and PPI as an empirical third-line rescue H. pylori treatment. This study was conducted by analyzing 70 consecutive prospectively registered patients who failed two times H. pylori eradication. All of them received endoscopy for H. pylori culture. Seven patients were lost to follow up. They were then treated according to the antibiotic susceptibility testing reports (Cultured group, n=39). Those who failed H. pylori culture were prescribed with a modified 14-day quadruple therapy containing esomeprazole 40 mg twice daily, amoxicillin 1 g twice daily, tetracycline 500 mg four times daily and metronidazole 500 mg three times daily (empirical group, n=24). Follow-up urea breath test was performed 8 weeks later. The eradication rates attained by Cultured group and empirical group were 89.7% (95% confidence interval [CI] = 72.72%-97.11%) and 58.3% (95% CI=36.61%-77.86%), in the per protocol analysis (p=0.004); 81.4%(95% CI=66.60%-91.61%) and 51.8% (95% CI=31.9%-71.29%), in the intention-to-treat analysis (P=0.014). Culture-guided therapy was the clinical factors influencing the efficacy of H. pylori eradication (OR: 0.16; 95% CI: 0.04-0.60, p=0.006). In conclusion, empirical 14-day modified quadruple therapy is not acceptable as an alternative third-line rescue H. pylori treatment probably but the success rate of the third-line susceptibility-guided treatment was only moderate (