Tailored therapy guided by genotypic resistance of clarithromycin and levofloxacin detected by polymerase chain reaction in the first-line treatment of Helicobacter pylori infection

Objectives: We aimed to explore the efficacy and safety of tailored therapy guided by genotypic resistance in the first-line treatment of Helicobacter pylori (H. pylori) infection in treatment-naive patients. Methods: Gastric mucosal specimens were taken during gastroscopy, and main mutations of clarithromycin- and levofloxacin-resistant genes were detected by polymerase chain reaction (PCR). Sensitive antibiotics were selected individually for treating H. pylori infection with tailored bismuth-containing quadruple therapy (BQT) consisting of esomeprazole 20 mg twice daily, bismuth potassium citrate 220 mg twice daily, amoxicillin 1 g twice daily, and clarithromycin 500 mg twice daily, or levofloxacin 500 mg once daily, or metronidazole 400 mg four times daily. Safety and patient compliance were assessed 1-3 days after eradication. Treatment outcome was evaluated by urea breath test 4-8 weeks after eradication. Results: One hundred and thirty-two treatment-naive patients with H. pylori infection were included. PCR results suggested resistance rates of 47.7% and 34.9% for clarithromycin and levofloxacin, respectively, and a dual resistance rate of 18.2%. Eradication rates of tailored BQT were 87.1% and 95.8% by intention-to-treat (ITT) analysis and per-protocol (PP) analysis, respectively. There was no statistically significant difference in the efficacy of 7-day clarithromycin-containing, 7-day levofloxacin-containing, and 14-day full-dose metronidazole-containing BQT (ITT analysis: P = 0.488; PP analysis: P = 0.833). The incidence of adverse events was 19.7%, and patient compliance was 97.7%. Conclusion: Tailored BQT guided by genotypic resistance can achieve satisfactory efficacy, safety, and patient compliance in the first-line treatment of H. pylori infection.