Trends of Carbapenem-Resistant Gram-negative Bacteria in China: A Surveillance Study Between 2015 and 2024

Abstract Objective To monitor the trends of carbapenem-resistant gram-negative bacteria to antimicrobial agents in healthcare facilities in major regions of China between 2015 and 2024. Methods Carbapenem-resistant gram-negative isolates from 74 hospitals in the country were tested for antimicrobial susceptibility using an automated method (imported or domestic AST instruments) supplemented by the disc diffusion method. Results were evaluated using the 2024 CLSI breakpoint. Results A total of 339 513 clinical isolates were collected between 2015 and 2024. Among clinical Enterobacterales isolates, the rate of carbapenem resistance was generally below 13%, except for Klebsiella spp., where it ranged from 20.4% to 21.9%. Most clinical Enterobacterales isolates are highly susceptible to tigecycline, colistin, and polymyxin B, with resistance rates ranging from 0.1% to 15.4%. The detection rate of meropenem-resistant Pseudomonas aeruginosa has decreased over six consecutive years, from 31.4% in 2018 to 21.5% in 2024. The detection rate of meropenem-resistant Acinetobacter baumannii remained modest, from 64.9% in 2015 to 68.3% in 2024. Conclusions Multidrug-resistant bacteria remain a significant challenge in clinical anti-infective treatment, and the surveillance of bacterial resistance and the rational use of antimicrobial agents need to be further strengthened to combat bacterial resistance.