摘要
目的研究温州地区分离的产超广谱β-内酰胺酶(ESBLs)肺炎克雷伯菌的基因型。方法随机挑取经全自动微生物分析仪鉴定的产ESBLs肺炎克雷伯菌35株,非产ESBLs肺炎克雷伯菌29株;用头孢噻肟、头孢噻肟/克拉维酸和头孢他啶、头孢他啶/克拉维酸双纸片扩散法对肺炎克雷伯菌进行ESBLs检测,采用聚合酶链反应(PCR)法对ESBLs阳性株进行TEM型、SHV型、CTX-M型、VEB型和PER型ESBLs基因检测,对PCR阳性产物进行测序确定基因型别,同时采用PCR法检测整合酶基因,对PCR产物进行测序确定整合酶类别。结果47株经双纸片扩散法确定为ESBLs阳性株中,经仪器法确定为阳性的为35株,仪器法的敏感性为73.4%;在17株经双纸片法确定为ESBLs阴性的菌株中,经仪器法确定为ESBLs阴性的有12株,仪器法的特异性为70.1%;TEM型、SHV型和CTX-M型阳性率分别为90.0%、86.7%和90.0%;整合酶基因阳性率为93.3%,经测序,所有TEM型为TEM-1 ESBLs;26株SHV型阳性的PCR产物经测序证实,SHV-12的有16株、SHV-11的有6株、SHV-2的有2株及SHV-1型2株,在27株CTX-M型中,CTX-M-14型有18株、CTX-M-15型9株。结论温州地区肺炎克雷伯菌临床分离株的ESBLs基因主要为CTX-M型和SHV型,CTX-M-14和SHV-12是主要的基因型。
OBJECTIVE To investigate the genotypes of ESBLs in clinical isolates of Klebsiella pneumoniae isolated from Wenzhou. METHODS Thirty-five isolates of ESBLs-produeing K. pneumoniae and 29 isolates of non-ESBLs-producing K. pneumoniae determined by VITEK 60 fully automated Analyzer, were selected randomly for test. The isolates were investigated for the presence of ESBLs by the CLSI-recommended confirmatory tests PCR detection of biaTEM, blaSHV, blaCTX-M, blaVEB, blaPER and int Ⅰ and were carried out with the previously reported oligonucleotide primers. The PCR products were sequenced on an ABI PRISM 3730 automated sequencer. RESULTS Forty-seven and 17 isolates of K. pneumoniae were ESBLs-producing and non-ESBLs-producing isolates determined by double-disk diffusion test, respectively. Compared with the results of double-disk diffusion test, the sensitivity and specificity of VITEK 60 fully automated Analyzer for determining ESRLs were 73.4% and 70. 1%, respectively. Thirty ESBLs-producing isolates were selected randomly for determining the genotype of ESBLs. The positive rates of blaTEM, blaSHV and bla CTX-M were 90.0%, 86.7% and 90.0%, respectively. Twenty-eight （93.3%） of 30 isolates were positive for int Ⅰ . All TEM-type genes were TEM-1. Of 26 isolates harboring blaSHV, 16, 6, 2 and 2 isolates carried blaSHV-12, blaSHV-11,blaSHV-1, and blaSHV-2, respectively. Eight and 9 isolates harbored hlaCTX M-14 and bla CTX-M-15. CONCLUSIONS blaCTX-M-14 And blaSHV-12 are main genotypes of ESBLs genes in ESBLs-producing K. pneumoniae isolated from Wenzhou.
出处
《中华医院感染学杂志》
CAS
CSCD
北大核心
2008年第12期1670-1672,共3页
Chinese Journal of Nosocomiology
