Department of Epidemiology and Biostatistics, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA.
Infect Control Hosp Epidemiol. 2010 Jun;31(6):607-12. doi: 10.1086/652775.
Active surveillance to detect patients colonized with methicillin-resistant Staphylococcus aureus (MRSA) is increasingly practiced in healthcare settings. However, inpatients may already become sources of transmission before appropriate precautions are implemented.
To examine the frequency of MRSA contamination of commonly touched skin and environmental surfaces before patient carriage status became known.
We conducted a 6-week prospective study of patients who were identified by use of polymerase chain reaction (PCR) at hospital admission as having nasal MRSA colonization. Skin and environmental contamination was assessed within hours of completion of PCR screening.
There were 116 patients identified by PCR screening as having nasal MRSA colonization during the period from mid-April to May 2008, of whom 83 (72%) were enrolled in our study. Overall, MRSA was detected on the skin of 38 (51%) of 74 patients and in the environment of 37 (45%) of 83 patients. Of 83 environmental culture samples, 63 (76%) were obtained within 7 hours after PCR results became available, and 73 (88%) were obtained before wards were notified of PCR results. Of the 83 MRSA-colonized patients, 15 (18%) had contaminated their environment 25 hours after admission, and 29 (35%) had contaminated their environment 33 hours after admission. Thirty-two (39%) of the 83 patients had roommates, 13 (41%) of whom contaminated their environment. The median interval from admission to PCR result was 20 hours, and the median interval from PCR result to notification was 23 hours. An increased quantity of MRSA cultured from a nasal sample was significantly associated with contamination.
Before any contact precautions can be implemented, newly identified MRSA carriers frequently have contaminated their environment with MRSA and have contamination of commonly examined skin sites. In hospitals that perform active surveillance, strategies are needed to minimize delays in screening or to preemptively identify patients at high risk for disseminating MRSA.
在医疗机构中，越来越多的人采用主动监测来检测耐甲氧西林金黄色葡萄球菌（MRSA）定植的患者。然而，在采取适当的预防措施之前，住院患者可能已经成为传播源。
在患者携带状态被发现之前，检测常见接触皮肤和环境表面的 MRSA 污染频率。
我们进行了一项为期 6 周的前瞻性研究，对通过聚合酶链反应（PCR）在入院时鉴定为鼻 MRSA 定植的患者进行研究。在完成 PCR 筛查后数小时内评估皮肤和环境污染情况。
在 2008 年 4 月中旬至 5 月期间，通过 PCR 筛查共发现 116 例鼻 MRSA 定植患者，其中 83 例（72%）纳入本研究。总体而言，74 例患者中有 38 例（51%）的皮肤和 83 例患者中有 37 例（45%）的环境中检测到 MRSA。在 83 个环境培养样本中，63 个（76%）是在 PCR 结果出来后 7 小时内获得的，73 个（88%）是在病房收到 PCR 结果之前获得的。在 83 例 MRSA 定植患者中，有 15 例（18%）在入院后 25 小时污染了环境，有 29 例（35%）在入院后 33 小时污染了环境。83 例患者中有 32 例（39%）有室友，其中 13 例（41%）污染了环境。从入院到 PCR 结果的中位数间隔为 20 小时，从 PCR 结果到通知的中位数间隔为 23 小时。从鼻样本中培养出的 MRSA 数量增加与污染显著相关。
在采取任何接触预防措施之前，新发现的 MRSA 携带者经常会将 MRSA 污染其环境，并污染常见的皮肤部位。在进行主动监测的医院中，需要采取策略来尽量减少筛查延迟或预先识别传播 MRSA 风险较高的患者。
