RESUMEN
Background: Several large clinical trials and meta-analyses have shown about 20% failure to eradicate Helicobacter pylori [H.pylori], necessitating investigations for second-line treatments. The aim of this study was to evaluate the effects of clarithromycin-containing quadruple regimen after nitroimidazole-containing quadruple therapy failure
Methods: Thirty two patients who had failed 10-day H.pylori treatment with omeprazole, amoxicillin, bismuth subcitrate, and metronidazole [OABM] regimen and 31 patients who had failed 10-day treatment with omeprazole, amoxicillin, bismuth subcitrate, and furazolidone [OAMF] regimen entered the study. They all received omeprazole [20 mg], amoxicillin [1 gr], bismuth subcitrate [240 mg] and clarithromycin [500 mg] twice a day for 10 days. Eight weeks after treatment, H. pylori eradication was assessed by 14C-urea breath test
Results: Totally 61 patients completed the study. According to intention to treat [ITT] analysis, eradication rates by second-line OABC regimen were 84.37% [95% CI= 71.7-96.9%] in OABM group and 77.41% [95% CI= 62.71-92.11%] in OABF group [p=0.756]. Per-protocol [pp] eradication rates were 87.09% [95% CI= 75.2-98.8%] and 82.75% [95% CI= 79.4-96%], respectively [p=0.638]. Also the cumulative eradication rates by OABC regimen were 80.9% [95% CI= 71.2-90.6%] and 85% [95% CI= 75.9-94%] according to ITT and PP analyses, respectively. Severe side effects were reported in 3.1% of the patients
Conclusion: Regarding ideal eradication rate [>80%] and very low adverse effects, it seems that clarithromycin-containing quadruple therapy can be an encouraging regimen after nitroimidazole-containing regimen failure