BACKGROUND The eradication rate of first-line Helicobacter pylori treatment is only 70-85% and has been decreasing due to the increase in antibiotic resistance. The aim of this study was to evaluate the efficacy of bismuth-containing quadruple therapy as second-line treatment for H. pylori infection based on treatment duration.

METHODS We prospectively enrolled 227 patients that were found to have persistent H. pylori infection after first-line proton-pump inhibitor-clarithromycin-amoxicillin triple therapy. Patients were randomized to 1-week (112 patients) and 2-week (115 patients) quadruple therapy with tripotassium dicitrate bismuthate 300 mg q.i.d., metronidazole 500 mg t.i.d., and tetracycline 500 mg q.i.d. and esomeprazole 20 mg b.i.d. The eradication rate, drug compliance, and adverse events were compared based on treatment duration.

RESULTS The eradication rates were 72/112 (64.3%, 95% CI: 0.504-0.830) and 71/92 (77.2%, 0.440-0.749) with 1-week group, and 95/115 (82.6%, 1.165-2.449) an 88/94 (93.6%, 1.213-5.113) with 2-week group by intention-to-treat therapy (p = .002) and per-protocol analysis (p = .001), respectively. The adverse events increased as the treatment durations increased from 7 to 14 days (20.0 and 42.5%, respectively, p < .001). However, there was no significant difference in the patient compliance or the rate of major adverse events between the 1- and 2-week groups (6.3 and 12.5%, respectively, p = .133).

CONCLUSION Two-week bismuth-containing quadruple therapy was more effective than the 1-week treatment, and should be considered for second-line treatment in Korea.