Antimicrobial Resistance Profile of Helicobacter pylori in Shenzhen, China: A Retrospective Study From 2021 to 2024

The escalating antibiotic resistance of Helicobacter pylori (H. pylori) poses a significant threat to global public health. Continuous local surveillance is crucial due to substantial geographical and temporal variations in resistance patterns.

This study aimed to characterize the antimicrobial resistance profile of H. pylori in Shenzhen, China, between 2021 and 2024, and to assess temporal trends and demographic associations.

We conducted a retrospective analysis of patients who underwent gastroscopy at Shenzhen Hospital of Southern Medical University from March 2021 to October 2024. Gastric mucosal biopsies were collected for H. pylori culture, and antimicrobial susceptibility testing was performed using the agar dilution method.

Among culture-positive isolates, 225 were from treatment-naïve patients and 975 from previously treated patients. Resistance rates in the treatment-naïve vs. previously treated groups were: clarithromycin 17.8% vs. 68.0%, metronidazole 87.1% vs. 97.4%, levofloxacin 11.1% vs. 50.9%, amoxicillin 0.4% vs. 3.1%, and furazolidone 0% vs. 0.1%. No tetracycline-resistant isolates were identified. Significant temporal increases were observed in secondary resistance to clarithromycin, amoxicillin, and metronidazole, as well as in the prevalence of multidrug resistance (all p < 0.05). No sex-based differences were detected in either primary or secondary resistance rates (all p > 0.05). Secondary resistance to clarithromycin, metronidazole, and levofloxacin varied significantly across age groups (p < 0.05), whereas primary resistance rates did not.

Between 2021 and 2024, H. pylori isolates in Shenzhen exhibited high resistance rates to metronidazole, clarithromycin, and levofloxacin, while susceptibility to amoxicillin, furazolidone, and tetracycline remained preserved. Secondary resistance rates increased progressively over time, accompanied by a growing burden of multidrug resistance. Bismuth-containing quadruple therapy and high-dose dual therapy are recommended as first-line empirical regimens for treatment-naïve patients, whereas susceptibility-guided therapy is warranted for those with prior treatment failure.