[Molecular epidemiology of carbapenem resistant Klebsiella pneumoniae in a hospital in Beijing].

Objective: To reveal the molecular epidemiological characteristics of Carbapenem-Resistant Klebsiella pneumoniae (CRKP) isolated from a three level teaching hospital in Beijing. Methods: Pulsed field gel electrophoresis (PFGE) was carried out to subtyping 375 CRKP isolated in that hospital between May 2010 and October 2015. Fifteen strains were chose based on the PFGE patterns to be analyzed by multi-locus sequence typing (MLST) and detection of carbapenem-resistance genes. One strain (A1502) was selected for whole genome sequencing and analyzing. Results: The 375 CRKP were divided into 140 PFGE types, among which five types contained more than five strains. The dominant types were distributed in different time periods and wards. Among the 15 strains tested by MLST and carbapenem-resistance genes detection, 13 were ST11 strains carrying KPC-2 gene. By genome-based typing, A1502 was clustered together with strains from other hospitals of Beijing but far from the strains from Shanghai and Hangzhou. Conclusion: The CRKP epidemic clone (ST11 clone carrying KPC-2) has been spreading within single hospital and across different hospitals in Beijing.