多重聚合酶链反应快速鉴别葡萄球菌及mecA基因检测

目的：建立快速鉴定葡萄球菌及检测mecA基因的多重聚合酶链反应（PCR）诊断方法。方法：以葡萄球菌16SrRNA、金黄色葡萄球菌的nuc基因以及耐甲氧西林葡萄球菌（MRS）的mecA基因合成3对引物，采用多重PCR扩增法，快速鉴定葡萄球菌，同时判断MRS菌株。结果：107株葡萄球菌的16SrRNA基因扩增片段全部为阳性．与常规鉴定结果符合率为100％；nuc基因阳性48株。阴性59株，与金黄色葡萄球菌核酸酶试验一致；以PBP2a乳胶凝集试验结果为金标准，苯唑西林（含2％NaClMHA）及头孢西丁纸片扩散法的敏感性为98．7％和100％，特异性分别为75．0％和82．1％：PCR扩增法的敏感性和特异性均为100％。结论：多重PCR法能快速准确地从临床分离菌株中鉴别葡萄球菌，并可同步对mecA基因进行准确检测。

Multiplex polymerase chain reaction assay for the rapid identification of staphylococcus and simultaneous detection of mecA gene from the clinical isolates

Objective:To establish a rapid and sensitive multiplex polymerase chain reaction (PCR) assay for the identification of staphylococcus aureus or coagulase-negative staphylococcus (CNS) and detection of mecA gene from the cliical isolates.Methods:The 16SrRNA (staphylococcus genus specific),nuc (S.aureus specific) and mecA (a deter minant of MRS) genes were amplified by multiplex PCR.According to the result of gel electrophoresis,the clinical isolates were identified and mecA gene was detected simultaneously.Results:All 107 clinical staphylococcal isolates showed 16srRNA-positive by PCR,and compared with the results of routine assay,the coincidence rate was 100% 48 strains in the aureus isolates showed nuc-positive and all CNS showed negative,it was consistent with the result of the nuclease test;78 isolates showed mecA-positive,29 isolates were negative,compared with the result of rapid latex agglutination test,both the sensitivity and the specificity were 1005.In the oxacillin (2% Nacl MHA) and cefoxitin disk diffusion tests,the sensitivity was 98.7% and 100% respectively and the specificity was 75.0% and 82.15% respectively.Conclusion:The multiplex PCR offexs a rapid and precise test for the identification of staphylococcus from the clinical isolates and detection of mecA gene simultaneously.