Phenotypic and genotypic characteristics of persistent methicillin-resistant Staphylococcus aureus bacteremia in vitro and in an experimental endocarditis model.
Phenotypic and genotypic characteristics of persistent methicillin-resistant Staphylococcus aureus bacteremia in vitro and in an experimental endocarditis model.
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DOI：
10.1086/595738
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发表时间：
2009-01-15
期刊：
影响因子：
--
通讯作者：
Bayer AS
中科院分区：
文献类型：
--
作者：
Xiong YQ;Fowler VG;Yeaman MR;Perdreau-Remington F;Kreiswirth BN;Bayer AS
持续性MRSA菌血症（PB）代表金黄色葡萄球菌感染的一个重要子集，并与不良临床结果相关。我们分析了39例菌血症患者（21例PB，18例菌血症缓解[RB]）MRSA分离株的相关体外表型和基因型特征。我们还比较了在实验性心内膜炎模型（IE）中选择的PB和RB菌株的内在毒力和对万古霉素的反应性。PB和RB分离株在被认为影响血管内感染的几个体外特征方面存在显著差异。PB分离株表现出显着更耐阳离子防御素hNP-1，增强膜流动性，并大大增加粘附纤连蛋白，纤维蛋白原，和内皮细胞。在基因型上，PB分离株具有较高的SCCmec II、CC 30和spa 16频率;以及较高的agr III型、cap 8、tst-1和cna携带率。最后，在感染性心内膜炎模型中，原型PB菌株比RB对照菌株对万古霉素治疗更具耐药性，尽管毒力特征相同。我们的研究结果表明，PB分离株可能具有特定的毒力特征，可将其与RB分离株区分开来。这些数据表明，可以开发方法来实时识别PB风险较高的患者，从而优化抗MRSA治疗策略的有效性。
Persistent MRSA bacteremia (PB) represents an important subset of Staphylococcus aureus infections and correlates with poor clinical outcomes. We profiled relevant in vitro phenotypic and genotypic characteristics of MRSA isolates from 39 persons with bacteremia (21 had PB and 18 had resolving bacteremia [RB]). We also compared the intrinsic virulence and responsiveness to vancomycin of selected PB and RB strains in an experimental endocarditis model (IE). PB and RB isolates differed significantly with regard to several in vitro characteristics that are believed to impact endovascular infections. PB isolates exhibited significantly more resistance to the cationic defensin hNP-1, enhanced membrane fluidity, and substantially greater adhesion to fibronectin, fibrinogen, and endothelial cells. Genotypically, PB isolates had higher frequency of SCCmec II, CC30, and spa 16; and higher rates of agr type III, cap8, tst-1, and cna carriage. Finally, a prototypic PB strain was more resistant to vancomycin treatment in the infective endocarditis model than a RB comparator strain, despite equivalent virulence profiles. Our findings indicate that PB isolates may have specific virulence signatures that distinguish them from RB isolates. These data suggest that methods might be developed to identify patients at higher risk for PB in real-time, thereby optimizing the effectiveness of anti-MRSA therapeutic strategies.
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影响因子：
15.3
作者：
Que, YA;Haefliger, JA;Piroth, L;François, P;Widmer, E;Entenza, JM;Sinha, B;Herrmann, M;Francioli, P;Vaudaux, P;Moreillon, P
通讯作者：
Moreillon, P
影响因子：
6.4
作者：
Fowler, Vance G., Jr.;Nelson, Charlotte L.;Gill, Steven R.
通讯作者：
Gill, Steven R.
影响因子：
3.1
作者：
Dhawan, VK;Yeaman, MR;Bayer, AS
通讯作者：
Bayer, AS
影响因子：
6.4
作者：
Dhawan, VK;Yeaman, MR;Bayer, AS
通讯作者：
Bayer, AS
影响因子：
3.1
作者：
Bayer, AS;Prasad, R;Yeaman, MR
通讯作者：
Yeaman, MR