Effect of Fluoroquinolone Resistance on 14-day Levofloxacin Triple and Triple Plus Bismuth Quadruple Therapy

Objective: Levofloxacin has been proposed to replace clarithromycin for Helicobacter pylori treatment. Seven-and 10-day fluoroquinolone triple therapies have generally failed to achieve cure rates of > 90%, whereas 14-day therapy has achieved 95% success. The aim was to assess the efficacy and effect of fluoroquinolone resistance on 14-day levofloxacin-containing triple therapy with or without the addition of bismuth. Design: Helicobacter pylori-positive patients with functional dyspepsia or healed peptic ulcers were randomized to receive lansoprazole 30 mg b.i.d., amoxicillin 1000 mg b.i.d., and levofloxacin 500 mg daily with (B-LAL) or without (LAL) bismuth potassium citrate 220 mg b.i.d. for 14 days. Eradication was assessed by 13 C-urea breath testing 4 weeks after completing treatment. Antimicrobial susceptibility was by the agar dilution method. Success was defined as PP success >= 90%. Results: A total of 152 of 161 patients (81 LAL and 80 B-LAL) enrolled completed treatment. The PP rates were 94.6% (70/74; 95% CI, 86.9-97.9%)/ with B-LAL and 85.9% (95% CI, 76.5-91.9%) with LAL (p =.07); the ITT eradication rates were 87.5% (95% CI, 78.5-93.1%) with B-LAL and 82.7% (95% CI, 73-89.4%) with LAL (p =.39). Levofloxacin resistance was present in 30.3%. Treatment success was excellent with susceptible strains (97.5%) versus resistant strains (70.6%) for B-LAL and 97.3% versus 37.5% for LAL, respectively. Conclusions: Fourteen-day fluoroquinolone therapy was highly effective when fluoroquinolone resistance rates are < 12%. The addition of bismuth maintained effectiveness with fluoroquinolone resistance as high as 25%.