Antimicrobial resistance surveillance of clinical isolates collected from paediatric and adult patients of intensive care units in China from 2017 to 2022

Abstract This study analysed bacterial infections and antimicrobial resistance (AMR) profiles of the top five pathogens in adult intensive care units (ICUs) and paediatric ICUs (PICUs) in China from 2017 to 2022, aiming to inform AMR surveillance and treatment guidelines. Antimicrobial susceptibility was assessed via automated systems or the Kirby-Bauer method, interpreted per Clinical and Laboratory Standards Institute breakpoints, and analysed using WHONET 5.6. 22,278 and 152,117 unduplicated clinical bacterial isolates were collected from 17 PICUs and 44 adult ICUs. The rate of Gram-negative bacteria was higher in adult ICUs than in PICUs (78.5% vs. 62.6%, P < 0.001). The top five clinical isolates in both departments were Staphylococcus aureus , Acinetobacter baumannii , Klebsiella pneumoniae , Pseudomonas aeruginosa , and Escherichia coli. From 2017 to 2022, E. coli , K. pneumoniae , and P. aeruginosa generally showed decreased resistance to most antimicrobial agents in adult ICUs, but increased resistance in PICUs. Resistance of A. baumannii and S. aureus to most antimicrobial agents decreased in both PICUs and adult ICUs. The resistance proportions of E. coli to ceftazidime-avibactam, ceftriaxone, and imipenem; K. pneumoniae to ceftazidime-avibactam and ceftriaxone; and P. aeruginosa to amikacin were higher in PICUs than in ICUs. For other detected antibacterial agents, all five pathogens showed higher resistance in adult ICUs than in PICUs ( P < 0.05). These data reveal a severe AMR burden in ICUs, with notable differences between PICUs and adult ICUs. Enhanced ICU-specific AMR surveillance, rigorous infection control, and optimised antibiotic stewardship are imperative to counter multidrug-resistant pathogens. Although escalating resistance trends remain a major concern in PICUs, significant reductions in resistance for several pathogens in adult ICUs likely reflect the impact of strengthened antimicrobial stewardship and infection control programs in China.