[Genomic subtyping of nosocomial transmission of carbapenem resistant Klebsiella pneumoniae].

Abstract

Objective: To analyze the genomic epidemiological subtyping of carbapenem resistant Klebsiella pneumoniae (CRKP) isolated from a Third-class A hospital in Zhengzhou. Methods: From December 4, 2019 to January 10, 2020, 67 strains of CRKP were isolated from the samples submitted by the clinical departments of a Third-class A teaching hospital in Zhengzhou for microbiological testing. Multi-locus sequence typing (MLST) and carbapenem resistance genes were identified by whole genome sequencing and sequence analysis. Based on the whole genome SNP, the phylogenetic tree was constructed, and 67 CRKP strains were divided into clonal groups. The isolation ward and date of each clone group were analyzed. Results: Sixty-seven CRKP strains were classified into four MLST types (STs), of which 64 were ST11. There were 62 ST11 strains carrying blaKPC-2 gene. Based on genome-wide SNP phylogenetic tree, 64 ST11 strains were divided into four clone groups, two of which were dominant clone groups, including 33 and 27 strains respectively; the other two clone groups only contained 2 strains respectively. There was no aggregation of the dominant clones in the isolation department and date. Conclusion: Multiple clonal groups of ST11 strain carrying blaKPC-2 gene are differentiated during spreading, and they can spread in parallel and independently in the same hospital.