产CMY型AmpC酶费劳地枸橼酸杆菌的耐药机制研究  

Study on antibiotic resistance of novel CMY-type AmpC β-Lactamase from Citrobacter freundii

作　　者：张晓坤[1] 徐韫健[2] 廖伟娇[2] 江洁华[3] 李翊泉[3] 黎文成[1] 李勰璘[1] 

机构地区：[1]广州医学院荔湾医院检验科,510170 [2]广州医学院附属第一医院检验科,510000 [3]广州医学院附属第一医院输血科,510000

出　　处：《国际检验医学杂志》2010年第10期1078-1080,共3页International Journal of Laboratory Medicine

基　　金：广东省科技厅项目(2008B060600046);广州市医药卫生科技项目(编号:2007-YB-156)

摘　　要：目的研究产CMY型AmpC酶费劳地枸橼酸杆菌的耐药机制。方法应用VITEK-2药敏卡S检测4株费劳地枸橼酸杆菌的MIC,用PCR技术扩增ESBLs、AmpC酶基因、Ⅰ类整合子及插入序列ISEcp1B,对PCR产物进行DNA测序,并进行质粒接合试验以了解耐药基因的转移。结果 4株费劳地枸橼酸杆菌对青霉素类、头孢菌素类、喹诺酮类、氨基糖甙类抗生素均表现为耐药,但对呋喃类和碳青霉烯类表现为敏感;β-内酰胺酶基因的检出情况:TEM-1(2/4)、SHV-1(2/4)、CTX-M-G1(1/4)、DHA(2/4),Ⅰ类整合子(2/4),ISEcp1B(1/4);质粒接合试验证实其中3株费劳地枸橼酸杆菌的质粒上都含有CMY基因,为可转移质粒。结论 4株费劳地枸橼酸杆菌的β-内酰胺酶耐药基因、插入序列、Ⅰ类整合子和可转移质粒检出率较高,对费劳地枸橼酸杆菌多重耐药的形成起了重要作用。Objective To investigate the antibiotic resistance of novel CMY-type AmpC A3-Lactamase from four Citrobacrer freundii. Methods MIC susceptibility method was used to analyze the drug resistance of four strains; the genotype of ESBLs, AmpC, I and the insert sequence ISEcplB were amplified by multiple PCR, the PCR products were sequenced subsequently. Conjugation experiment was carried out to study the transfer of drug resistance. Results Four strains were resistant to penicillins, eeph-alosporin, quinolone, aminoglyeoside , and susceptible to nitrofuran, carbapenem. The genotype of β-lactamases , Ingegron I and the insert sequence were ： TEM-1 （2/4）. SH V- 1 （ 2/4 ）. CTX-M-G1 （ 1/4 ） . DH A （ 1/4 ） and Integron Ⅰ （ 1/4 ）. ISEeplB （ 1/4 ）. The plasmids from three of four strains were proved to have blaCMY by conjugation experiment. Conclusion There were high positive percentages of the genotype of β-1actamases , I and the insert sequence, transfer plasmid in four Citrobacter freundii,these were the main reason that caused Citrobacter freundii multi-drug resistance.

关 键 词：头孢菌素酶 抗药性 细菌 弗劳地枸橼酸杆菌 

分 类 号：R446.5[医药卫生—诊断学]