几种检测耐甲氧西林金黄色葡萄球菌方法的评价

目的对三种检测耐甲氧西林葡萄球菌方法的可靠性和临床实用性进行评价。方法以PCR检测金黄色葡萄球茵甲氧西林决定因子A（mecA）为金标准，按临床实验室标准化委员会（CLSI）操作规程用苯唑西林纸片扩散法、头孢西丁纸片扩散法、苯唑西林琼脂稀释法对临床分离的155株金黄色葡萄球菌进行检测。结果155株金黄色葡萄球菌经mecA基因检测，耐甲氧西林金黄色葡萄球菌（MRSA）为61．9％（96／155）；头孢西丁纸片扩散法检测MRSA的敏感性和特异性均为100％；苯唑西林纸片扩散法的敏感性为95．8％，特异性为91．5％；苯唑西林琼脂稀释法的敏感性为100％，特异性为98．3％；头孢西丁纸片扩散法优于苯唑西林纸片扩散法和苯唑西林琼脂稀释法。结论头孢西丁纸片扩散法操作简便、敏感性高、特异性好、结果可靠，可作为医院微生物实验室日常工作中检测耐甲氧西林葡萄球菌的常规方法。

Evaluation of Several Methods for Detection of Methicillin-resistant Staphylococcus Aureus

ObjectiveTo evaluate the reliability and clinical practicability of three methods in detection of methicillin-resistant staphylococcus aureus (MRSA).MethodsAccording to the CLSI standard operating instructions,the 155 strains of clinical isolated staphylococcus aureus were tested by the oxacillin disk diffusion test,the cefoxitin disk diffusion test,and the oxacillin agar dilution test.Simultaneously detection by PCR of staphylococcal mecA gene were used as a reference method.ResultsConfirmed by mecA gene,61.9% (96/155) strains were MRSA.Both sensitivity and specificity of cefoxitin disk diffusion test in the detection of MRSA were 100%,which is superior to the oxacillin disk diffusion test(95.8% and 91.5%) and the oxacillin agar dilution test(100% and 98.3%).ConclusionThe Cefoxitin disk diffusion test is reliable,simple and convenient for routine detection and confirm of MRSA in the clinical laboratories.