Abstract
OBJECTIVE: Antimicrobial resistance (AMR) represents one of the most pressing global public health threats. This study aimed to analyze the distribution and antimicrobial resistance profiles of Carbapenem-resistant Gram-negative Bacteria (CRGNB) isolated from pediatric patients in Sichuan Province, China, in order to provide evidence to support rational antimicrobial use and infection prevention and control in clinical practice. METHODS: This retrospective study included non-duplicate CRGNB isolates recovered from hospitalized children aged ≤14 years in 134 medical institutions across Sichuan Province from 2021 to 2025. Bacterial identification and antimicrobial susceptibility testing were performed according to a unified surveillance protocol. CRGNB was defined, in accordance with CLSI M100, 34th edition (2024), as isolates resistant to at least one carbapenem (imipenem, meropenem, or ertapenem). Data were analyzed using WHONET 5.6. RESULTS: A total of 2523 CRGNB isolates were collected. Isolates from male patients accounted for 56.4% (1422/2523), and the largest proportion of isolates was from the 29 days to ≤1 year age group (41.8%, 1054/2523). The five most frequently isolated species were Klebsiella pneumoniae (41.8%, 1055/2523), Acinetobacter baumannii (22.1%, 558/2523), Escherichia coli (10.0%, 252/2523), Enterobacter cloacae complex (9.3%, 235/2523), and Pseudomonas aeruginosa (6.4%, 162/2523), with respiratory specimens accounting for most isolates (59.6%, 1504/2523). Enterobacterales showed susceptibility rates >96% to tigecycline and polymyxin B. K. pneumoniae showed 87.5% susceptibility to ceftazidime-avibactam. A. baumannii exhibited low resistance only to polymyxin B and tigecycline (2.3% and 2.5%, respectively). P. aeruginosa showed 100% susceptibility to ceftazidime-avibactam and polymyxin B. CONCLUSION: CRGNB infections among children in Sichuan Province remain severe and display marked regional characteristics, with infants constituting a high-risk population. The increasing prevalence of multidrug-resistant organisms poses a substantial challenge to clinical management and warrants close surveillance and targeted intervention.