肺炎克雷伯菌临床分离株产广谱和超广谱β-内酰胺酶的基因型研究  

Study on the genotypes of spectrum β-lactamases and ESBLs in clinical isolates of Klebsiella pneumoniae

作　　者：胡龙华[1] 余方友[2] 熊建球[1] 贾坤如[1] 胡晓彦[1] 况九龙[1] 桂炳东[1] 

机构地区：[1]南昌大学第二附属医院,南昌330006 [2]温州医学院附属第一医院,温州325000

出　　处：《中国抗生素杂志》2009年第6期372-375,共4页Chinese Journal of Antibiotics

摘　　要：目的了解产ESBLs肺炎克雷伯菌临床分离株的耐药性及其基因型分布特征,指导临床进行抗感染治疗,更好地控制耐药菌株的播散。方法对38株经双纸片试验确认为ESBLs表型阳性的肺炎克雷伯菌采用纸片扩散法进行药物敏感性试验;采用PCR法对ESBLs阳性株进行TEM型、SHV型、CTX-M型、VEB型和PER型ESBL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38株产ESBLs的肺炎克雷伯菌对青霉素类和头孢菌素类耐药性十分严重,对庆大霉素和复方磺胺甲唑的耐药率也均>90%,未检测到耐亚胺培南和美罗培南的菌株。38株ESBLs阳性菌株检测到3种ESBLs型,分别为TEM型、SHV型和CTX-M型,VEB型和PER型没有被检出。CTX-M型、TEM型和SHV型阳性率分别为92.1%(35/38)、84.2%(32/38)、76.3%(29/38)。整合酶基因阳性率为94.7%(36/38)。经测序,所有TEM型均为TEM-1广谱β内酰酶。29株SHV型阳性的PCR产物经测序证实,SHV-12有19株,SHV-11有4株,SHV-2有3株,SHV-28有2株及SHV-1有1株。35株CTX-M型中,CTX-M-14有22株,CTX-M-15有13株。同时检测到3种基因的有22株(57.9%),同时检测到2种基因的有14株(36.8%)。整合酶基因PCR产物经测序为Ⅰ类整合子。结论产ESBLs肺炎克雷伯菌临床分离株的耐药性及多重耐药性严重,Ⅰ类整合子是其多重耐药和耐药性传播的主要原因;CTX-M-14及SHV-12为肺炎克雷伯菌产ESBLs的主要基因型。Objective To investigate the genotypes of ESBLs in clinical isolates of Klebsiella pneumoniae isolated from Nanchang. Methods Thirty-eight isolates of ESBLs-producing Klebsiella pneumoniae, which were determined by double paper disk diffusion,were screened for antimicrobial susceptibility test. PCR detection of blaSHV, blaCTX-M, blaVEB, blaPER and intl was carried out with the previously reported oligonucleotide primers. The PCR products were sequenced on an ABI PRISM 3730 automated sequencer. Results The resistance of ESBLs-producing isolates to antimicrobial agents was serious. All tested isolates were susceptible to imipenem and meropenem. Three of 5 ESBL genotypes were detected. The positive rates of blaCTX-M ,blaTEM and blaSHV were 92.1% （35/38） ,84.2% （32/38） and 76.3% （29/38）,respectively. Thirty-six （94.7%）of 38 isolates were positive for intl. All TEM-type genes were TEM-1. Of 29 isolates harboring blaSHV, 19, 4, 3 and 1 isolates carried blaSHV-12, blaSHV-11, blaSHV-1, and blaSHV-2, respectively. Twenty-two and 13 isolates harbored blaCTX-M-14 and blaCTX-M-15 Meanwhile 22 （57.9%） and 14 （36.8%） of 38 ESBLs-producing isolates carried three ESBLs genes and two ESBL genes. Conclusions blaCTX-M-14 and blaXHV-12 were main genotype of ESBLs genes in clinical isolates of ESBLs-producing Klebsiella pneumoniae.

关 键 词：肺炎克雷伯菌 Β-内酰胺酶 基因型 

分 类 号：R378[医药卫生—病原生物学]