Kluytmans Jan
Amphia Hospital Breda and VUmc Medical University Amsterdam, The Netherlands.
J Hosp Infect. 2007 Jun;65 Suppl 2:100-4. doi: 10.1016/S0195-6701(07)60024-3.
The cornerstones of infection control are the identification of patients who are contagious for others, and taking appropriate control measures. Microbiological detection of pathogens can take from several minutes or hours (microscopy) up to several days (culture-dependent detection). Currently, meticillin-resistant Staphylococcus aureus (MRSA) is one of the most important pathogens in nosocomial infection control, and detection using culture will take 1 5 days. This delay in the result of culture leads to a suboptimal control strategy. In low endemic settings like The Netherlands, patients who are considered at increased risk of MRSA carriage are treated in isolation until the results of culture have confirmed the absence of MRSA. On average this will take 4 to 5 days. As approximately 95% of these patients will not carry MRSA, this leads to a high number of unnecessary isolation days. This could be reduced by a rapid diagnostic test. In high endemic settings, admission screening and isolation until proven negative reduces the incidence of MRSA in high-risk units of the hospital. This has been predicted in a mathematical model and has been confirmed in intervention studies. Such a strategy can be implemented much more efficiently when a rapid diagnostic test is available. Recently, a real-time polymerase chain reaction test has become available that can detect MRSA directly from patient samples and takes less than 2 hours. The first results have been encouraging, although there are strains that are not detected. This test is not primarily intended to be used as a diagnostic device but rather as a screening tool for infection control. Many other screening tests are under development which may prove useful tools for the optimization of infection control in the near future.
感染控制的基石是识别具有传染性的患者，并采取适当的控制措施。病原体的微生物检测时间从几分钟或几小时（显微镜检查）到几天（依赖培养的检测）不等。目前，耐甲氧西林金黄色葡萄球菌（MRSA）是医院感染控制中最重要的病原体之一，采用培养法进行检测需要1至5天。培养结果的这种延迟导致控制策略不够理想。在荷兰这样的低流行地区，被认为携带MRSA风险增加的患者会被隔离治疗，直到培养结果证实不存在MRSA。平均而言，这需要4至5天。由于这些患者中约95%不会携带MRSA，这导致了大量不必要的隔离天数。通过快速诊断测试可以减少这种情况。在高流行地区，入院筛查并隔离直至证明为阴性可降低医院高危科室中MRSA的发病率。这在数学模型中已有预测，并在干预研究中得到了证实。当有快速诊断测试可用时，这样的策略可以更有效地实施。最近，一种实时聚合酶链反应测试已经可用，它可以直接从患者样本中检测出MRSA，耗时不到2小时。尽管有一些菌株无法检测到，但初步结果令人鼓舞。该测试主要不是用作诊断设备，而是用作感染控制的筛查工具。许多其他筛查测试正在开发中，可能在不久的将来成为优化感染控制的有用工具。
