Abstract:Objective To understand the antimicrobial resistance and genetic characteristics of clinically isolated Pseudomonas aeruginosa in Jiangsu area. Methods Pseudomonas aeruginosa isolated from sentinel hospitals in Jiangsu area from 2016 to 2021 were collected, susceptibility of bacterial isolates to 19 kinds of 10 categories of antimicrobial agents were detected with broth dilution method. Bacterial strains were performed whole genome sequencing and multilocus sequence typing, antimicrobial resistance genes were scanned and analyzed through comprehensive antimicrobial resistance database. Results From 2016 to 2021, 101 strains of Pseudomonas aeruginosa isolated from patients at sentinel hospitals in 12 cities were collected through the Pathogenic Bacteria Identification Network. Antimicrobial susceptibility testing results showed that all strains were resistant to 8 kinds antimicrobial agents in 6 categories, including chloramphenicol of amphenicols, compound sulfamethoxazole of sulfonamides, cefotaxime and cefazolin of cephalosporins, tetracycline of tetracyclines, ampicillin and ampicillin/sulbactam of penicillins, as well as amoxicillin/clavulanic acid of β-lactams, 45.54% of the isolates were carbapenem-resistant strains. Resistance rates of two carbapenems imipenem and meropenem were 45.54% and 39.60%, respectively, 63.36% of the strains were resistant to more than 10 kinds of antimicrobial agents. A total of 35 kinds of antimicrobial-resistant phenotypes were found, among which one strain was extensively resistant to 19 antimicrobial agents. The most drug-resistant strain was AMC-AM-SAM-CZ-CTX-C-TE-SXT (31.69%, n=32). Multilocus sequence typing analysis revealed 75 ST types, and clustering analysis revealed that ST 262 was at the center point, with 11 subtypes or branches genetically evolved. Whole genome scanning revealed 18 kinds of 6 categories antimicrobial resistance genes, the carrying status and phenotype of the crpP gene were completely consistent. Conclusion From 2016 to 2021, the clinically isolated Pseudomonas aeruginosa in Jiangsu area showed severe antimicrobial resistance, the resistance rates to two carbapenems and the proportion of strains resistant to more than 10 kinds of antimicrobial agents are higher than other provinces in China and should be paid highly attention.