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bioRxiv · 10.1101/2024.10.25.620218

Clinical characteristics, drug-resistance genes and virulence analysis of carbapenem-resistant Klebsiella pneumoniae

He, J.·Zhang, P.·Li, C.·Xie, N.·Yin, Y.·Wang, G.·Liang, T.·Liu, Y.
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Abstract

OBJECTIVEThe aim was to investigate the clinical infection characteristics, risk factors and convergence of carbapenem-resistant and hypervirulent Klebsiella pneumoniae(hv-CRKP) in our hospital, in order to provide scientific basis for the rational use of antibiotics in the clinic. METHODSCRKP strains were isolated from clinical specimens of 44 patients in central intensive care unit (CICU), neurosurgery intensive care unit (NICU) and emergency intensive care unit (EICU) of our hospital in 41 months. The clinical manifestations of the patients were analyzed, and the hypermucoviscous phenotype was defined by string test. The drug resistance gene, virulence gene and capsular specific serotype of the isolated strains were detected by polymerase chain reaction (PCR) technology, and the gene of CRKP producing KPC enzyme was sequence. RESULTSThe incidence of sepsis in 44 patients with CRKP infection was 25.0%, and the overall treatment failure rate was 38.6%. All the 44 strains of CRKP produced KPC enzyme, and all of them were blaKPC-2 (100%);14 strains (31.8%) were positive in string test; 23 strains (52.3%) were found to have virulence related genes, including 10 strains (22.7%) of rmpA, 16 strains (36.4%) of iucA and 19 strains (43.2%) of peg-344. 5 strains (11.4%) were capsule-specific serotypes and 13 strains (29.5%) were identified as hv-CRKP. CONCLUSIONThe mechanism of CRKP resistance in our hospital is blaKPC-2, the detection rates of virulence gene, string test positive and hypervirulent capsular specific serotype are all relatively high in CRKP, there are not a few Klebsiella pneumoniae with carbapenem-resistant and hypervirulent.

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He, J., Zhang, P., Li, C., Xie, N., Yin, Y., Wang, G., Liang, T., Liu, Y.. 2024-10-25. Clinical characteristics, drug-resistance genes and virulence analysis of carbapenem-resistant Klebsiella pneumoniae. https://doi.org/10.1101/2024.10.25.620218

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