社区及医院感染中产β-内酰胺酶的大肠埃希菌和肺炎克雷伯菌细菌耐药性及质粒分析

Drug Resistance and Resistant Plasmids of ESBLs Producing Escherichia coli and Klebsiella pneumoniae in Community and Nosocomial Infections

目的探讨社区和医院感染中产ESBLs的大肠埃希菌(ECO)和肺炎克雷伯菌(KPN)耐药性及细菌质粒谱特点。方法药敏试验采用改良KirbyBauer法,细菌质粒DNA采用碱变性少量快速提取法,用χ2检测。结果医院感染ECO耐药率明显高于社区感染(P<0001),ECO细菌质粒较KPN分子量大,表现多源性、多样性、分布较广,仅在ECO中发现3对同源基因质粒谱。结论医院感染致病ECO有多源多样的细菌耐药质粒,为医院感染顽固的耐药菌,应加强医院感染易感因素控制,以防感染流行。

OBJECTIVE To explore the characteristic of drug resistance and resistant plasmids of ESBLs producing Escherichia coli and Klebsiella pneumoniae in community and nosocomial infections. METHODS One hundred and twenty isolated strains were subjected to ESBLs test, double disk synergy tests (DDST), drug susceptibility tests performed by Kirby Bauer disk diffusion method, plasmid profile and investigation of clinical epidemiology of the cases. RESULTS The resistance rates of ESBLs producing strains in nosocomial infection were higher than the ones in community infection (P<0 001). Of 120 strains 89 (E.coli had 73 strains, K. pneumoniae had 16, totally 74 2%)contained plasmid. The size of E.coli plasmid profile was larger than K. pneumoniae one, it appeared multi geneous, diversified features and wide distribution. Only 3 pairs of homogeneous plasmids were detected in E.coli strains. CONCLUSIONS Strains of ESBLs producing E.coli in nosocomial infection are stubborn resistant bacilii in hospital. In order to prevent nosocomial infection from happening, the susceptible factors control must be strengthened.