Drug sensitivity analysis of extended spectrum β lactamases-producing Klebsiella pneumoniae and Escherichia coli

Objective To investigate the antimicrobial resistance and the isolating rate of extended spectrum β lactamases(ESBLs)-producing Klebsiella pneumoniae and Escherichia coli to rationalize clinical medication.Methods To collect the samples of isolated Klebsiella pneumoniae and Escherichia coli from January 2007 to December 2009 and to identify with common biochemistry and Marcel API20E system.To detect ESBLs by disk diffusion confirmation test.The drug sensitivity test was performed by disk diffusion method.Results 281 strains of Escherichia coli and 174 strains of Klebsiella pneumoniae were verified to produce ESBLs,the positive rates were 36.2% for Escherichia coli and 40.9% for Klebsiella pneumoniae respectively.ESBLs-producing bacteria were highly resistant to antibiotics with β lactamases,5.4%~25.6% to amikacin,cefoxitin,cefoperazone-sulbactam,piperacillin-tazobactam,amoxicillin-clavulanic acid,ticarcillin-clavulanic acid,and 65.1%~88.9% to ciprofloxacin,centamicin and SMZ-TMP.There were no ESBLs-producing strains of Escherichia coli and Klebsiella pneumoniae with resistance to imipenem.Conclusion The problem of ESBLs-producing bacteria is getting more serious.Clinical physicians ought to understand the drug-resistance characteristics and the change trend of ESBLs-producing Escherichia coli and Klebsiella pneumoniae,which is important to use antibiotics rationally,delay the production of bacterial drug-resistance and control the spread of drug-resistant strains.