Study on phenotypic and genotypic characterization of clinical multidrug-resistant Escherichia coli isolates
10.3760/cma.j.issn.0254-6450.2012.12.018
- VernacularTitle:137株多耐药大肠埃希菌表型及耐药机制研究
- Author:
Hui-Zhong WANG
1
;
Hang SHA
;
Qian CHEN
;
Yan-Ju GUO
;
Bing-Hua ZHU
;
Shao-Hui WANG
;
De-Lu GAO
Author Information
1. 解放军第三○五医院检验科
- Keywords:
Escherichia coli;
Multidrug-resistance;
Resistance mechanism
- From:
Chinese Journal of Epidemiology
2012;33(12):1276-1278
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study the mechanisms on drug susceptibility and resistance of clinically multidrug-resistant Escherichia coli isolates,to provide information on related treatment.Methods The susceptibility of E.coli strains that isolated from different kinds of samples in the last 3 years on drugs was analyzed by agar dilution test,with strains that exhibiting resistances to cefotuxime,ciprofloxacin and amikacin simultaneously collected for further analysis.Resistant genes which mediate resistance to β-lactamases,fluoroquinolone and aminoglycoside as well as phylogenic type were detected by PCR amplification while genetic relation was analyzed by PFGE.Transferability of resistant plasmids was identified by conjugation test.Results In total,137 multidrug-resistant E.coli isolates were collected.Only 1％ of the isolates exhibited resistance to both imipenem and meropenem while 4％ of the strains were resistant to piperacillin/tazobactam.Most (85％) of the isolates were positive to ESBL and majority of them produced CTX-M.Target substitution and production of methylases were the main mechanisms causing resistance to fluoroquinolones and aminoglycosides respectively.Conclusion The main source of clinical multidrug-resistance was collected from urine samples.Carbapenem and enzyme inhibitor-containing antibiotics seemed to be the available antibiotics that were sentitive to the clinically multidrug-resistant E.coli isolates.
