Analysis of the Prevalence, Drug Resistance Genes and Evolution of Carbapenem-Resistant <i>Klebsiella pneumoniae</i> in Lishui, China from 2015 to 2024

Background: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is increasingly recognized as a significant global public health threat. However, comprehensive long-term epidemiological surveillance of clinical CRKP isolates in China (Lishui city) remains limited. Objectives: To address this gap, we conducted a retrospective observational study spanning 2015 to 2024, aiming to evaluate the prevalence, drug resistance genes, and evolution of clinical CRKP isolates. Methods: Clinical data and drug resistance profiles of CRKP isolates from hospitalized patients were retrieved from medical records. Antibiotic resistance genes were analyzed using whole-genome sequencing. Fourier-transform infrared spectroscopy (FTIR) was employed to examine the genetic evolution of the bacteria. Results: A total of 6 676 K. pneumoniae strains were detected, including 714 CRKP strains. The detection rate of CRKP fluctuated from 9.77% in 2015 to a low of 3.00% in 2016, then increased to 10.38% in 2024. Clinical risk factors for CRKP included intensive care unit (ICU) admission, hospitalization, and age over 60 years. All 25 CRKP strains were identified as ST11 type and carried blaKPC-2and blaSHV enzyme genes. The FTIR typing revealed that the predominant circulating strains from 2020 to 2024 belonged to the same clone. Conclusions: The detection rate of CRKP in our hospital has shown an increasing trend over the past decade. The blaKPC-2gene is the predominant drug resistance determinant in CRKP, and horizontal transmission of the same clone is evident.