Villari P, Sarnataro C, Iacuzio L
Department of Health and Preventive Sciences, University "Federico II," 80131 Naples, Italy.
J Clin Microbiol. 2000 May;38(5):1740-6. doi: 10.1128/JCM.38.5.1740-1746.2000.
Coagulase-negative staphylococci, especially Staphylococcus epidermidis, are increasingly important nosocomial pathogens, particularly in critically ill neonates. A 3-year prospective surveillance of nosocomial infections in a neonatal intensive care unit (NICU) was performed by traditional epidemiologic methods as well as molecular typing of microorganisms. The aims of the study were (i) to quantify the impact of S. epidermidis on NICU-acquired infections, (ii) to establish if these infections are caused by endemic clones or by incidentally occurring bacterial strains of this ubiquitous species, (iii) to evaluate the use of different methods for the epidemiologic typing of the isolates, and (iv) to characterize the occurrence and the spread of staphylococci with decreased glycopeptide susceptibility. Results confirmed that S. epidermidis is one of the leading causes of NICU-acquired infections and that the reduced glycopeptide susceptibility, if investigated by appropriate detection methods such as population analysis, is more common than is currently realized. Typing of isolates, which can be performed effectively through molecular techniques such as pulsed-field gel electrophoresis but not through antibiograms, showed that many of these infections are due to clonal dissemination and, thus, are potentially preventable by strict adherence to recommended infection control practices and the implementation of programs aimed toward the reduction of the unnecessary use of antibiotics. These strategies are also likely to have a significant impact on the frequency of the reduced susceptibility of staphylococci to glycopeptides, since this phenomenon appears to be determined either by more resistant clones transmitted from patient to patient or, to a lesser extent, by strains that become more resistant as a result of antibiotic pressure.
凝固酶阴性葡萄球菌，尤其是表皮葡萄球菌，日益成为重要的医院病原体，在危重新生儿中尤为如此。我们采用传统流行病学方法以及微生物分子分型技术，对一家新生儿重症监护病房（NICU）进行了为期3年的医院感染前瞻性监测。本研究的目的是：（i）量化表皮葡萄球菌对NICU获得性感染的影响；（ii）确定这些感染是由地方性克隆株还是由该常见菌种偶然出现的菌株引起；（iii）评估不同方法用于分离株流行病学分型的效用；（iv）描述糖肽敏感性降低的葡萄球菌的发生和传播情况。结果证实，表皮葡萄球菌是NICU获得性感染的主要原因之一，并且如果通过适当的检测方法如群体分析进行调查，糖肽敏感性降低的情况比目前所认识到的更为常见。分离株的分型可通过脉冲场凝胶电泳等分子技术有效进行，但不能通过抗菌谱进行，结果表明许多此类感染是由于克隆传播，因此，通过严格遵守推荐的感染控制措施以及实施旨在减少抗生素不必要使用的方案，有可能预防这些感染。这些策略也可能对葡萄球菌对糖肽敏感性降低的频率产生重大影响，因为这种现象似乎要么是由患者之间传播的更具耐药性的克隆株决定，要么在较小程度上是由因抗生素压力而变得更具耐药性的菌株决定。
