Nosocomial Escherichia coli and Klebsiella pneumoniae Isolates in 2003-2006:Their Distribution and Resistance Analysis

OBJECTIVE To review and analyze the distribution and antimicrobial resistance of nosocomial Escherichia coli and Klebsiella pneumoniae.METHODS Disk diffusion test(Kirby-Bauer)was used for anti-microbial susceptibility.Extended spectrum β-lactamases(ESBLs)were detected by double disk synergy test and disk diffusion confirmatory test.AmpC enzyme was detected by the three dimensional assay.RESULTS The positive rate of the production of ESBLs and AmpC enzyme was 34.6% and 5.0%,respectively.The production rate of both ESBLs and AmpC enzyme positive was 2.4%.Isolated rate of ESBLs-producing strains in sputum and urine of the inpatients in respiratory ward and urinary ward was higher than others.All strains were 100% susceptible to meropenem and imipenem but resistant to 15 other antimicrobials in different degrees.CONCLUSIONS The isolated rate of β-lactamases-producing strains is increasing year by year.These strains are multi-drug resistant.Attention must be paid to their detection and surveillance.