10-Year Trends in Helicobacter pylori Eradication Rates by Sitafloxacin-Based Third-Line Rescue Therapy

Background/Aims:Sitafloxacin (STFX)-containing regimens were shown to be useful options for third-lineHelicobacter pylorieradication therapy. It is reported that resistance to quinolone is also increasing globally. Therefore, we conducted an analysis of the current efficacy of a 10-day -STFX-containing third-line rescue therapy and the changes of antibiotic resistance toH. pyloricompared to 2 historical controls.Methods:Patients in whom eradication treatment using both first- and second-line triple therapies failed were enrolled from 2014 to 2015. The minimum inhibitory concentrations of STFX, clarithromycin (CLR), amoxicillin (AMX), metronidazole (MTZ) and thegyrAmutation status of theH. pyloristrains were determined before treatment. After that, the patients received a 10-day triple therapy containing esomeprazole (20 mg, b.i.d.), AMX (500 mg, q.i.d.) and STFX (100 mg, b.i.d.; 10-day EAS). The eradication rate and the rate of antibiotic resistance toH. pyloriwere compared with 2 previous reports about STFX-containing third-line rescue therapies in 2009-2011 and 2012-2013. To explore the association between the eradication rates of regimens containing STFX, AMX and proton pump inhibitors and the location ofgyrAmutation or AMX resistance, a meta-analysis was attempted.Results:The overall eradication rates, the eradication rate forgyrAmutation negative- and positive- strains were 81.6% (31/38), 94.7% (18/19) and 68.4% (13/19) respectively. These rates were not significantly different from 2 previous reports. The resistant rates to STFX, CLR, AMX, MTZ and the rate of presence of mutation ingyrAwere 50.0, 81.6, 36.8, 78.9 and 50.0%, respectively, which was also not significantly different from 2 previous reports. A meta-analysis showed that the relative risk of the eradication failure is significantly lower ingyrAmutation negative strains compared togyrAmutation positive strains, and that the relative risk of the eradication failure is significantly lower ingyrAmutation at D91 compared togyrAmutation at N87 (p< 0.001 andp= 0.022, respectively). Moreover, a meta-analysis showed that the relative risk of the eradication failure is significantly lower in AMX-sensitive strains compared to AMX-resistant ones.Conclusion:Changes in the rate of antibiotic resistance toH. pyloriwere not observed from 2009 to 2015. The status ofgyrAmutation is a superior marker for predicting successful eradication in STFX/AMX-containing triple regimen as a third-line rescue therapy.