Detection of extendedspectrum βlactamases and antimicrobial resistance of Escherichia coli isolated from different clinical specimens of a county hospital in 2012-2014

Abstract:

ObjectiveTo analyze the distribution and antimicrobial resistance of Escherichia coli (E. coli) causing  infection in a county hospital, and provide  basis for clinical treatment of  E. coli infection. MethodsFrom 2012 to 2014, all kinds of clinical specimens in a hospital were performed bacterial culture, identification， and antimicrobial susceptibility testing； extendedspectrum βlactamases (ESBLs) were initially screened by broth microdilution method, and confirmed by disc diffusion method； data were  statistically analyzed by WHONET 5.6 and SPSS 19.0 software. Results271 isolates of E. coli were detected,  and mainly isolated from midstream urine (26.94%). The detection rate of ESBLsproducing E. coli was 49.82%, most were isolated from sputum specimens ( 56.52%), but there was no significant difference in detection rates of ESBLsproducing E.coli isolated from different specimens （P＞0.05）. Antimicrobial susceptibility testing results showed that the resistance rate of E.coli to penicillins was the highest (>90%), to cefalotin and cefuroxime were both >75%, susceptibility rates to amikacin and piperacillin / tazobactam were both high (resistance rates＜10%), carbapenemresistant strain was not found, resistance rates of ESBLsproducing strains to most antimicrobial agents were significantly higher than nonESBLsproducing strains.ConclusionE. coli is mainly isolated from midstream urine specimens, antimicrobial resistance of ESBLproducing  strains is more serious.