Inefficacy of Triple Therapy and Comparison of Two Different Bismuth-containing Quadruple Regimens as a Firstline Treatment Option for Helicobacter pylori

BACKGROUND/AIM Increasing resistance of Helicobacter pylori to antimicrobials necessitated the development of new regimens and the modification of existing regimens. The present study aimed to compare the efficacy of two bismuth-containing quadruple regimens-one including clarithromycin (C) instead of metronidazole (M) and triple therapy. PATIENTS AND METHODS Patients with H. pylori infection given the following regimens were sequentially enrolled in this retrospective study: (1) Triple therapy: Lansoprazole 30 mg b.i.d., clarithromycin 500 mg b.i.d., and amoxicillin 1 g b.i.d., (2) bismuth group C: Lansoprazole 30 mg b.i.d., clarithromycin 500 mg b.i.d., amoxicillin 1 g b.i.d., and bismuth subsalicylate 524 mg b.i.d., and (3) bismuth group M: Lansoprazole 30 mg b.i.d., amoxicillin 1 g b.i.d., metronidazole 500 mg t.i.d., and bismuth subsalicylate 524 mg b.i.d. for 14 days. Gastroscopy and 14 C-urea breath test were performed before enrollment, and urea breath test was repeated four weeks after the treatment. RESULTS At per-protocol analysis, the eradication rates were 64.7% (95% confidence interval 60.4-68.7) with the triple therapy (n = 504), 95.4% (95% confidence interval 91.5-99.4) with the bismuth group C (n = 501), and 93.9% (95% confidence interval 89.7-98.7) with the bismuth group M (n = 505). The eradication rates were similar between the two bismuth groups (P > 0.05) but significantly greater than that of the triple therapy (P < 0.05). CONCLUSION In our study, both of the bismuth-containing quadruple therapies reached high eradication rates, whereas triple therapy was shown to be ineffective. Moreover, clarithromycin may also be a component of bismuth-containing quadruple therapy.