Evolution of antibiotic resistance pattern of Helicobacter pylori in Spanish children: A 10-year multicenter study

To delineate the evolution of antibiotic resistance over the past decade in Spanish children diagnosed with Helicobacter pylori (H. pylori) infection.

An observational, retrospective, multicenter study was conducted in Madrid, Spain. This study included children diagnosed with H. pylori infection via endoscopy with positive culture and antimicrobial susceptibility testing between 2011 and 2020.

A total of 1205 patients (56.7% female) were included in the study. Of these, 18.7% had previously undergone unsuccessful treatment. The resistance to the antibiotics tested was as follows: clarithromycin, 42.9% (n = 504, [95% confidence interval, CI: 40.1%-45.8%]); metronidazole, 24% (n = 280, [95% CI: 21.5%-26.5%]); rifampicin, 14.8% (n = 120, [95% CI: 12.4%-17.4%]); levofloxacin, 5.2% (n = 58, [95% CI: 3.9%-6.6%]); amoxicillin, 2.6% (n = 30, [95% CI: 1.7%-3.6%]); and tetracycline, 0.9% (n = 10, [95% CI: 0.4%-1.6%]). The double resistance rate was 12.2% (n = 143, [95% CI: 10.4%-14.2%]). During the study period, antibiotic resistance remained relatively stable, with a notable decrease in metronidazole (incidence rate ratio [IRR]: 0.941, [95% CI: 0.898-0.985], p = 0.01) and double resistance (IRR: 0.933, [95% CI: 0.875-0.995], p = 0.03) values. The overall eradication rate was 76.6% (n = 752, [95% CI: 73.8-79.2%]), which was significantly higher in patients without prior treatment. The temporal progression of eradication rates showed a substantial increase, with an average annual increase of 2.9% (IRR: 1.029, [95% CI: 1.015-1.043], p < 0.001).

The prevalence of antibiotic resistance in our setting (Madrid, Spain) was remarkably high and remained stable throughout the study period, except for a notable decline in metronidazole and double resistance.