Detection of Extended-spectrum Beta-lactamases and Analysis of Antibiotic Resistance in Clinical Isolates Of Klebsiella pneumoniae

Objective To determine the antibiotic resistance and the productive rate of extended-spectrum-beta-lactamases(ESBLs)in the clinical isolates of Klebsiella penumonlae.Methods 482 strains of Klebsiella penumonlae were isolated from the patients admitted to the Affiliated Hospital of Qingdao University Medical College during the years 2003 and 2004,the antibiotic susceptibility test was peformed by Kirby-Baucer disk diffusion method,ESBLs production was performed by the standard disk diffusion method.Results ESBLs productive rate increased significantly from 28.9%to 40.1% during the years 2003 and 2004.ESBLs-producing strains had higher resistance rate than that of non-ESBLs-producing ones.beta-lactamase inhibitor combinations(cefoperazone/tazobactam and piperacillin /tazobactam),fouth-generation cephalosporins(cefepime)and carbapenems(imipenem and meropenem)showed high activities against the ESBLs-producing strains.Imipenem and meropenem had the most effective antibiotic activity among them.Conclusions ESBLs production of Klebsiella penumonlae had significantly increased.ESBLs-producing strains wre the most sensitive to carbapenems.Measures should be taken to control the spread of ESBLs-producing Klebsiella penumonlae.