Optimizing Detection of MRSA Carriage

描述（由申请方提供）：金黄色葡萄球菌是医疗保健相关感染的主要原因。估计有40万例S. 2003年，美国医院发生了金黄色葡萄球菌感染。约60%的S。金黄色葡萄球菌医院感染是由耐甲氧西林的S.金黄色葡萄球菌（MRSA）。据估计，MRSA感染每年导致近19，000名住院美国患者死亡。而S.已知金黄色葡萄球菌定殖于各种解剖部位，其主要栖息地是前鼻孔的上皮。因此，使用鼻拭子培养积极筛查MRSA，然后对携带者进行接触隔离，是美国医院广泛采用的感染控制策略，以防止这种微生物在患者之间交叉传播。社区相关MRSA（CA-MRSA）菌株的出现，由不同的遗传特征和导致皮肤和软组织感染的趋势定义，正在迅速改变MRSA的流行病学。以脉冲场型（PFT）USA 300克隆为代表的CA-MRSA菌株可能在体表具有不同于医疗保健相关MRSA（HA-MRSA）菌株的定殖模式。随着CA-MRSA流行的进展，CA-MRSA菌株越来越成为医疗相关感染的常见原因。在我们的初步研究中，我们发现很大一部分MRSA定植的患者是在皮肤上定植的，但不一定是在鼻孔上。此外，对于一些患者，我们能够使用海绵（可以对大面积皮肤进行采样）而不是拭子来回收MRSA。本提案的具体目的是（1）阐明急性护理医院患者中MRSA的定植模式，并研究基于海绵的筛查方法的灵敏度，以及（2）通过确定定植于不同解剖部位的菌株的基因型，确定CA-和HA-MRSA菌株定植模式的差异。该试验的主要目的是开发一种灵敏的MRSA定植筛查方法。这样的方法将作为一个有用的工具，在研究MRSA定植的动力学和评估感染控制措施的有效性，如载体的去殖民化。 公共卫生相关性：耐甲氧西林链球菌。金黄色葡萄球菌（MRSA）是美国卫生保健相关感染的主要原因。在许多医院，病人是否携带MRSA是通过培养鼻子来确定的。这项研究旨在确定是否有解剖部位在检测MRSA时比鼻子更敏感，以及海绵的使用是否增强了MRSA的检测。

DESCRIPTION (provided by applicant): Staphylococcus aureus is a major cause of healthcare-associated infection. An estimated 400,000 cases of S. aureus infection occurred in US hospitals in 2003. Approximately 60% of S. aureus hospital infections are caused by methicillin-resistant S. aureus (MRSA). It is estimated that MRSA infections are responsible for the death of nearly 19,000 hospitalized American patients annually. While S. aureus is known to colonize various anatomic sites, its primary habitat is the epithelium of the anterior nares. Therefore, active screening for MRSA using nasal swab culture followed by contact isolation of carriers is a widely practiced infection control strategy in US hospitals to prevent cross-transmission of this organism between patients. The advent of community-associated MRSA (CA-MRSA) strains, which are defined by distinct genetic traits and tendency to cause skin and soft tissue infection, is rapidly changing the epidemiology of MRSA. CA-MRSA strains, represented by the pulsed-field type (PFT) USA300 clone, may have a colonization pattern on the body surface that differs from healthcare- associated MRSA (HA-MRSA) strains. As the CA-MRSA epidemic progresses, CA-MRSA strains are increasingly becoming a common cause of healthcare-associated infections. In our preliminary study, we found that a substantial portion of patients who are colonized with MRSA are colonized on the skin, but not necessarily the nares. In addition, for some patients, we were able to recover MRSA using a sponge (which can sample a large area of the skin), but not swabs. The specific aims addressed in this proposal are (1) to elucidate the colonization patterns of MRSA among patients in an acute care hospital and investigate the sensitivity of sponge-based screening method, and (2) to identify the difference in colonization patterns of CA- and HA-MRSA strains by determining the genotypes of the strains colonizing various anatomic sites. The main objective of this pilot is to develop a sensitive screening method for MRSA colonization. Such a method will then serve as a useful tool in studying the dynamics of MRSA colonization and evaluating the efficacy of infection control practices such as decolonization of carriers. PUBLIC HEALTH RELEVANCE: Methicillin-resistant S. aureus (MRSA) is a major cause of healthcare-associated infection in the United States. In many hospitals, whether a patient carries MRSA or not is determined by culturing of the nose. The proposed study aims to identify whether there are anatomic sites that are more sensitive in detecting MRSA than the nose, and whether the use of sponge enhances detection of MRSA.