Occurrence of CTX-M-3, CTX-M-15, CTX-M-14, and CTX-M-9 Extended-Spectrum β-Lactamases in Enterobacteriaceae Clinical Isolates in Korea

Abstract
Among 603 isolates of Enterobacteriaceae collected between June and November 2003 from three university hospitals within Korea, bla CTX-M-3 , bla CTX-M-15 , bla CTX-M-14 , and bla CTX-M-9 were detected in 41 isolates of species from five different genera of Enterobacteriaceae , Escherichia coli , Klebsiella pneumoniae , Citrobacter freundii , Enterobacter spp., and Serratia marcescens .