Molecular biological approach for a dignasis and me chanism of sepsis

我们建立了一种巢式聚合酶链反应快速灵敏诊断术后患者耐甲氧西林金黄色葡萄球菌（MRSA）菌血症的方法。6例正常志愿者血液标本均未检出mecA和TSST-1基因，血培养均为阴性。12份MRSA血培养标本均检测到mecA和TSST-1基因。在一份经血培养的表皮葡萄球菌菌落中，检测到mecA基因，但未检测到TSST-1基因。28份MRSA血培养阴性样本中，2份仍有mecA和TSST-1基因阳性。在这2例患者中，MRSA是通过培养从血液以外的标本中分离出来的。虽然血培养法鉴定MRSA至少需要48小时，但采用巢式PCR法在采血后3-4小时内即可确定mecA和TSST-1基因的存在。

We established a rapid and sensitive diagnostic method for methicillinresistant Staphylococcus aureus (MRSA) bacteremia in postoperative patients using nested polymerase chain reaction.mecA and TSST-1 genes were not detected in the blood samples of any of the 6 normal volunteers, which were negative by blood culture.In all the 12 samples from which MRSA was isolated by blood culture, mecA and TSST-1 genes were detected.In one sample from which S.epidermidis colonies grow after blood culture , mecA was detected but TSST-1 gene was not.Of 28 samples with blood cultures negative for MRSA,2 samples were still positive for mecA and TSST-1 genes.In these 2 patients, MRSA was isolated from specimens other than blood by culture.Although it took at least 48hr to identify MRSA by blood culture method, the presence of mecA and TSST-1 genes was determined by nested PCR method within only 3-4 hr after blood sampling.