【摘要】 目的了解β-内酰胺酶基因在大肠埃希菌和肺炎克雷伯菌连续分离株中的存在及流行情况,为临床用药及医院感染控制提供依据。方法连续收集2010年1-10月医院临床分离出的大肠埃希菌和肺炎克雷伯菌,应用微生物分析仪进行鉴定和药物敏感试验,应用双纸片扩散法进行ESBLs确认;PCR方法对菌株进行21种β-内酰胺酶基因检测。结果 159株细菌中有81株检测到TEM、SHV、OXA-1和CTX-M-1等12种耐药基因,123个基因片段,主要耐药基因为TEM和SHV,其中大肠埃希菌以TEM为主,占33.3%,肺炎克雷伯菌则以SHV为主,占27.9%,且有7株SHV和LEN双阳性菌株和2株LEN得以准确区分;有16种基因型,51.9%含有>2种耐药基因,其中产AmpC酶13株,4株与ESBLs并存。结论大肠埃希菌和肺炎克雷伯菌连续分离株β-内酰胺酶基因携带率高,多药耐药性严重;加强对产β-内酰胺酶基因菌株的监测十分重要,严格掌握抗菌药物的使用指征,防止耐药菌株的传播流行。更多还原

【Abstract】 OBJECTIVE To investigate the β-lactamase genes in continuously isolated Escherichia coli and Klebsiella pneumoniae strains so as to provide basis for clinical medication and conerol of nosocomial infection.METHODS The identification and drug susceptibility testing of clinical strains were performed by MicroScan auto-Scan4.The double-disk diffusion method was used to detect the ESBLs-producing strains.PCR was used for the detection of the 21 β-lactamase genes.RESULTS Totally 159 clinical strains were collected,among which 81 strains were confirmed to produce β-lactamases.There were 12 kinds of genes and 123 gene fragments such as TEM,SHV,OXA-1,and CTX-M-1.TEM was the most common type of the β-lactamase gene in the clinical strains of E.coli(33.3%),but SHV was the most common type in K.pneumoniae(27.9%).There were 16 genotypes and 51.9% of the strains produced more than two β-lactamase genes.Among 13 AmpC-producing strains,4 strains produced AmpC β-lactamases and ESBLs.CONCLUSION The carrying rate of β-lactamase gene is high in continuously isolated E.coli and K.pneumoniae strains in the locality and most strains are multidrug-resistant.It is very important to enhance the surveillance of the β-lactamase-producing strains and to strictly grasp the indication for antibiotic application so as to prevent the spread of the drug resistance strains.更多还原