Carbapenem resistance of KPC-possessing Enterobacteriaceae / 中华临床感染病杂志

ABSTRACT

Objective To evaluate 5 drug sensitivity tests in detecting carbapenem resistance of KPC-possessing Enterobacteriaceae.Methods Thirty-six Enterobacteriaceae isolates were collected from the First Affiliated Hospital,Cofiege of Medicine,Zhejiang Univeristy,including 32 of Klebsiella pneumoniae,1 of Escherichia coli,1 of Citrobacter freundii,1 of Klebsiella oxytoca,and 1 of Serratia marcescens,and the cacbapenemase producing was confirmed with PCR.Resistance to imipenem,meropenem and ertapenem was determined by agar dilution and disk diffusion tests,that to imipenem and meropehem was determined by ATB with G-5 panel,that to imipenem by BD Phoenix 100 with NMIC-109 panel,and that to imipenem and ertapenem by VITEK 2 Compact with AST-GN13 card.Results The resistance to imipenem determined by ATB,BD Phoenix100,VITEK 2 Compact,agar dilution and disk diffusion tests were 13.9%(5/36),11.1%(4/36),13.9%(5/36),22.2%(8/36)and 69.4%(25/36).ATB,agar dilution and disk diffusion tests reported 22.2%(8/36).55.6%(20/36)and 47.2%(17/36)as resistant to meropenem.VITEK 2 Compact,agar dilution and disk diflusion tests reported 69.4%(25/36),77.8%(28/36)and 88.9%(32/36)as resistant to ertapenem.The MICs of ertapenem determined by VITEK 2 Compact and agar dilution were≥2 μg/mL.Conclusion The sensitivity of agar dilution and agar disk diffusion is higher than other automatic methods in the identification of KPC-mediated carbapenem resistance,and ertapenem is a more sensitive indicator than mempenem and imipenem for screening KPC-possessing isolates.