Department of Medical Microbiology, Aberdeen Royal Infirmary, Foresterhill, Aberdeen AB252ZN, UK.
Int J Antimicrob Agents. 2011 Mar;37(3):202-9. doi: 10.1016/j.ijantimicag.2010.10.030.
Severe (life-threatening) meticillin-resistant Staphylococcus aureus (MRSA) infection continues to be treated with vancomycin despite accumulating evidence of poor outcome, increasing resistance and unachievable pharmacokinetic/pharmacodynamic (PK/PD) targets. The minimum inhibitory concentration (MIC) susceptibility breakpoint for vancomycin was recently reduced to 2 mg/L. Whilst the great majority of clinical isolates are thus still classified as susceptible, the available clinical evidence argues for a method-dependent breakpoint of 0.5 mg/L (broth dilution) or 1.0 mg/L (Etest), which would classify many strains as resistant, or at best intermediate. However, automated susceptibility testing systems are not currently capable of performing accurately at this low level, and such low breakpoints are unsatisfactory because the poor reproducibility of tests (plus or minus one doubling dilution) results in a critical non-reproducibility around the modal MIC of 1 mg/L described in most published data. Therefore, vancomycin should be used with caution in severe (life-threatening) staphylococcal disease and the MIC should always be reported by method. Daptomycin is generally preferred for bacteraemia/endocarditis and linezolid for pneumonia. Better outcome data for vancomycin, based on achievable PK/PD targets and using robust MIC tests, are urgently required.
严重（危及生命）的耐甲氧西林金黄色葡萄球菌（MRSA）感染仍然使用万古霉素治疗，尽管有越来越多的证据表明预后不良、耐药性增加和无法达到药代动力学/药效学（PK/PD）目标。万古霉素的最低抑菌浓度（MIC）敏感性折点最近已降低至 2mg/L。虽然绝大多数临床分离株仍被归类为敏感，但现有临床证据表明，依赖方法的折点为 0.5mg/L（肉汤稀释）或 1.0mg/L（Etest），这将使许多菌株归类为耐药，或者最好是中介。然而，自动化药敏检测系统目前无法在如此低的水平下准确地进行检测，而且如此低的折点并不令人满意，因为测试的重现性差（加或减一个倍比稀释）导致在大多数已发表的数据中描述的 1mg/L 模式 MIC 周围存在临界不可重现性。因此，万古霉素在严重（危及生命）的葡萄球菌疾病中应谨慎使用，并且应始终根据方法报告 MIC。达托霉素通常用于菌血症/心内膜炎，而利奈唑胺则用于肺炎。迫切需要基于可达到的 PK/PD 目标和使用稳健的 MIC 测试的万古霉素更好的疗效数据。
