绿脓假单胞菌多重耐药机制的研究  

Study on the multi-drug resistant mechanism of Pseudomonas aeruginosa

作　　者：顾兵[1] 童明庆[1] 赵文君[1] 倪芳[1] 魏源华[1] 

机构地区：[1]南京医科大学第一附属医院临床检验中心,210029

出　　处：《中华检验医学杂志》2006年第12期1097-1102,共6页Chinese Journal of Laboratory Medicine

摘　　要：目的调查我院2003-2005年临床分离多重耐药绿脓假单胞菌的氨基糖苷类修饰酶基因、β内酰胺酶编码基因和外膜通道蛋白oprD2基因存在状况；并研究整合子参与绿脓假单胞菌多重耐药的机制。方法纸片扩散法测定绿脓假单胞菌对14种抗菌药物的药物敏感性，并筛选出14株多重耐药菌株；聚合酶链反应检测氨基糖苷类修饰酶基因、β内酰胺酶编码基因和外膜通道蛋白oprD2基因；聚合酶链反应检测整合子5’保守区的整合酶基因和3’保守区的qacE△1-sulI基因。对整合酶基因的阳性扩增产物的限制性片段长度多态性分析进行整合子分类，整合子可变区扩增并测序。结果14株绿脓假单胞菌对14种抗菌药（哌拉西林等）的耐药率为14．3％-100．0％；氨基糖苷类修饰酶基因ant（2”）-Ⅰ、aac（3）-Ⅱ、aac（6’）-Ⅱ、aac（6’）-Ⅰ、ant（3”）-Ⅰ和aac（3）-Ⅰ检出率分别为78．6％、57．1％、57．1％、14．3％、7．1％、0；β内酰胺酶编码基因TEM和IMP的检出率分别为92．9％和42．9％，未检出VIM、OXA、PER、GES和SHV基因，1株外膜通道蛋白oprD2基因缺失；整合酶基因及qacE△1-sulI基因检出率分别为85．7％和78．6％，整合子可变区扩增有3种片段：1000、1300和1700，测序证实分别为aadA2、aadA6．odD和dfrⅫ-orfF-aadA2，其中aadA2是首次在绿脓假单胞菌的整合子中检出，aadA6-odD是一种新型的整合子可变区基因盒组合形式。Genbank号分别为DQ091178和DQ091179。结论我院多重耐药绿脓假单胞菌对B内酰胺类抗生素的耐药主要与TEM和IMP型耐药基因有关，对氨基糖苷类抗生素的耐药主要与氨基糖苷类修饰酶基因ant（2”）-Ⅰ、8aC（3）-Ⅱ和aac（6’）-Ⅱ有关；整合子参与了绿脓假单胞菌的耐药和多重耐药。Objective To survey the distribution of aminoglycoside-modifying enzyme genes, β- lactamase genes and the outer membrane protein OprD2 gene produced by multi-drug resistant Pseudomonas aeruginosa （P. aeruginosa） isolated in our hospital during the period from 2003 to 2005. And to investigate the mechanism of integron-mediated multi-drug resistance in these strains. Methods The antibiotic susceptibility of 14 different antibiotics of P. aeruginosa was tested by K-B method, and 14 multi-drug resistant strains were screened; aminoglycoside-modifying enzyme genes, β-1actamase genes and the outer membrane protein OprD2 gene were detected by polymerase chain reaction （PCR）; the integrase gene located in the 5＇ conserved segment and the qacE A 1-sulI gene located in the 3＇ conserved segment of integrons were also detected by PCR, and the classification of integrons was performed by analyzing the positive PCR products by using restriction fragment length polymorphism （RFLP） , the variable region of integrons was amplified and sequenced. Results Resistant rates of 14 strains of P. aeruginas against 14 kinds of antibiotic （piperacillin et al） ranged from 14. 3% to 100.0%; the detection rate of 6 aminoglyeoside-modifying enzyme genes, including ant（2＂）-Ⅰ、aac（3）-Ⅱ、aac（6＇）-Ⅱ、aac（6＇）-Ⅰ、ant（3＂）-Ⅰ and aae（3）- Ⅰ was 78.6%, 57. 1%, 57. 1%, 7. 1%, 14.3% and 0.0% respectively;the detection rate of β-laetamase gene TEM and IMP was 92. 9% and 42. 9% respectively, and none of the 14 strains possessed genes of VIM, OXA, PER, GES and SHV, 1 isolate of PA lost the outer membrane protein oprD2 gene, the detection rate of integrase genes and qaeE △1-sulI genes was 85.7% and 78. 6% respectively. Three different fragments （ 1.0 kb, 1.3 kb and 1.7 kb） of the variable region of integron were amplified, they were aadA2, aadA6-orfD and dfrⅫ-orfF-aadA2 identified by sequencing, among which, aadA2 gene cassette was first detected in integrons in P. aeruginas, and aa

关 键 词：假单胞菌 铜绿 Β内酰胺类 抗药性 多药 整合子 

分 类 号：R516[医药卫生—内科学]