摘要
目的了解万古霉素敏感性减低葡萄球菌临床分离株对β-内酰胺类、氨基糖苷类、四环素以及万古霉素耐药相关基因存在状况。方法采用含6μg/mL万古霉素脑心浸液琼脂从临床分离的葡萄球菌中筛选万古霉素中介葡萄球菌和万古霉素耐药葡萄球菌;采用菌谱分析法筛选异质性万古霉素耐药葡萄球菌;E-test法和琼脂稀释法检测其MIC值;PCR技术扩增mecA、aac(6')/aph(2'')、aph(3')-Ⅲ、tetM、vanA、vanB和vanC基因,并对阳性扩增产物进行测序。结果从100株临床分离葡萄球菌中检出7株异质性万古霉素耐药葡萄球菌,并从部分菌株中检出耐药基因,mecA、aac(6')/aph(2'')、aph(3')-Ⅲ基因检出率分别为85.7%,57.1%和85.7%,没有检出tetM、vanA、vanB和vanC。对PCR阳性扩增产物进行测序,BLASTn比对分析,与已登录基因库的相同基因序列具有高度同源性。结论同甲氧西林耐药葡萄球菌相似,万古霉素敏感性减低葡萄球菌携带多种耐药基因,耐药表型与基因分析支持该菌株多药耐药,该类菌株的检测对于指导临床合理用药具有积极意义。
Objective To determine the existence of the clinically relevant antibiotic resistant genes in clinical isolates of Staphylococcus with reduced susceptibility to vancomycin. Methods 100 stains of clinical isolates staphylococci were subjected to Brain Heart Infusion （BHI） vancomycin screen agar to screen vancomycin intermediate Staphylococcus or vancomycin resistant Staphylococcus, and then performed population analysis to detect heterogeneous vancomycin-resistant staphylococci （hVRS）. MICs of the staphylococci with reduced susceptibility to vancomycin were detected by E-test and by Mueller-Hinton agar Micro-dilution; Antibiotic resistant genes including mecA, aac（6＇）/aph（2＂）, aph（3＇）-III, terM, vanA, vanB and vanC were detected by PCR, and PCR products were sequenced. Results No vancomycin intermediate or resistant Staphylococcus was detected, but 7 strains of heterogeneous vancomycin-resistant staphylococci were isolated; the detective rates of mecA and aph（3＇）-III were both 85.7%, but 57.1% for aac（6＇）/aph（2＇9; no vanA, vanB, vanC or terM gene was detected from hVRS by PCR. Conclusions It is similar to methicillin resistant Staphylococcus aureus that heterogeneous vaneomyein-resistant staphylococci carry many clinically relevant antibiotic resistant genes and resistant to most of antibiotics. So, further study of the antibiotics resistance mechanism of Staphylococcus with reduced susceptibility to vancomycin should be kept focus on.
出处
《中国抗生素杂志》
CAS
CSCD
北大核心
2011年第4期292-296,共5页
Chinese Journal of Antibiotics
基金
江苏省自然科学基金(BK2006540)
苏州市卫生局科技兴卫青年专项基金(SWQ15)
关键词
葡萄球菌
耐药基因
万古霉素
Staphylococcus aureus
Antibiotic resistant genes
Vancomycin
