Metronidazole containing quadruple therapy for infection with metronidazole resistant Helicobacter pylori: a prospective study

Abstract

Metronidazole remains a key component of H. pylori infection therapy. It has been suggested that despite resistance, metronidazole may be effective when given at high dose with bismuth, tetracycline, and a proton pump inhibitor (quadruple therapy). To prospectively evaluate metronidazole quadruple therapy for treatment of metronidazole resistant H. pylori infection in the United States. Patients infected with metronidazole resistant H. pylori were prospectively prescribed 14 days of quadruple therapy consisting of metronidazole 500 mg t.d.s., tetracycline 500 mg q.d.s., two bismuth subsalicylate tablets q.d.s., and omeprazole 20 mg o.d. A total of 26 patients were entered into the study; 22 for their first treatment and four as re-treatment for failed therapy. Of the 26 patients, 24 were cured (cure rate 92%; 95% CI: 78–99%). Both treatment failures reported full compliance to 14 days of therapy. Side-effects were common and resulted in premature discontinuation of therapy in 31%. Premature discontinuation did not reduce the cure rate. Quadruple metronidazole combination therapy is effective despite the presence of metronidazole resistance and should be considered as either first line therapy or for failures of twice-a-day combination therapies.