BACKGROUND/AIMS Initial proton pump inhibitor (PPI)-based triple therapy for Helicobacter pylori (H. pylori) infection is less effective in patients with nonulcer dyspepsia (NUD) than those with peptic ulcer disease (PUD). To date, there have been no studies on the difference in eradication rates in NUD compared to PUD with regard to second-line therapy. Therefore, we retrospectively analyzed the difference in eradication rates of a second-line quadruple therapy for NUD and PUD patients.

METHODOLOGY Between June 2003 and December 2005, patients who failed to respond to initial PPI-based triple therapy, received 7 days of quadruple therapy (PPI b.i.d., bismuth 300mg q.i.d., metronidazole 500mg t.i.d., tetracycline 500mg q.i.d.) as a second-line treatment regimen. Four weeks after the completion of the course of medication, a 13C-urea breath test was performed for detection of H. pylori.

RESULTS A total of 87 patients received second-line quadruple therapy. Of these, 43 patients had NUD and 44 patients had PUD (19 gastric ulcers, 23 duodenal ulcers, 2 both ulcers). The eradication rates were 76.7% (33/43) in the NUD group and 90.9% (40/44) in the PUD group by per-protocol analysis. Therefore, the eradication rates in the NUD group were significantly lower than those in the PUD group (p = 0.034).

CONCLUSIONS A 7-day bismuth-based second-line quadruple therapy for H. pylori infection was less effective in patients with NUD than those with PUD. Therefore, a more potent second-line treatment regimen or extension of treatment duration of quadruple therapy should be considered for the eradication of H. pylori in patients with NUD.