Division of Infectious Diseases, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
J Antimicrob Chemother. 2010 May;65(5):1015-8. doi: 10.1093/jac/dkq050. Epub 2010 Mar 3.
The high prevalence of methicillin-resistant Staphylococcus aureus (MRSA) coupled with an increase in vancomycin use have induced vancomycin tolerance in MRSA, adversely affecting the outcome of MRSA bacteraemia. This study aimed to identify predictors of persistent MRSA bacteraemia (PMRSAB) in patients treated with vancomycin.
A retrospective, case-control study was performed at a university hospital in Korea from January 2006 to February 2009. Subjects included 96 patients who had MRSA bacteraemia and received vancomycin under therapeutic drug monitoring. We compared the clinical characteristics, management and outcomes of cases with PMRSAB (>or=7 days, n = 31) with controls with non-PMRSAB (<or=3 days, n = 32). Vancomycin MICs were determined by the Vitek 2 system.
Of 96 patients with MRSA bacteraemia, MRSA isolates from 21 patients (21.9%) showed a vancomycin MIC of 2 mg/L. Independent predictors of PMRSAB were: retention of implicated medical devices [odds ratio (OR), 10.35; 95% confidence interval (CI), 1.03-104.55]; MRSA infection of at least two sites (OR, 10.24; 95% CI, 1.72-61.01); and vancomycin MIC of 2 mg/L (OR, 6.34; 95% CI, 1.21-33.09). The frequency of side effects and mean trough serum vancomycin concentrations were not significantly different between the two groups. Sixteen patients with PMRSAB subsequently received teicoplanin +/- arbekacin, linezolid or quinupristin/dalfopristin, due to vancomycin failure or intolerance.
To minimize the risk of PMRSAB, early removal of implicated devices and evaluation for metastatic infections should be encouraged. Alternative antibiotic therapy is warranted for infections due to isolates with elevated vancomycin MICs, as well as for the high rates of side effects.
耐甲氧西林金黄色葡萄球菌（MRSA）的高流行率加上万古霉素的使用增加，导致 MRSA 出现万古霉素耐药性，从而对 MRSA 菌血症的治疗结果产生不良影响。本研究旨在确定接受万古霉素治疗的患者中持续性 MRSA 菌血症（PMRSAB）的预测因素。
本研究为 2006 年 1 月至 2009 年 2 月在韩国一所大学医院进行的回顾性病例对照研究。纳入了 96 例接受治疗药物监测下万古霉素治疗的 MRSA 菌血症患者。我们比较了 PMRSAB（>或=7 天，n=31）病例与非 PMRSAB（<或=3 天，n=32）病例的临床特征、治疗方法和结局。采用 Vitek 2 系统测定万古霉素 MIC。
96 例 MRSA 菌血症患者中，21 例（21.9%）MRSA 分离株的万古霉素 MIC 为 2mg/L。PMRSAB 的独立预测因素包括：留置相关医疗器械（比值比[OR]，10.35；95%置信区间[CI]，1.03-104.55）；MRSA 感染至少两个部位（OR，10.24；95%CI，1.72-61.01）；以及万古霉素 MIC 为 2mg/L（OR，6.34；95%CI，1.21-33.09）。两组患者不良反应的发生频率和平均谷浓度无显著差异。16 例 PMRSAB 患者因万古霉素耐药或不耐受，改用替考拉宁+或安巴培南、利奈唑胺或奎奴普丁/达福普汀。
为尽量减少 PMRSAB 的风险，应鼓励早期去除相关器械，并评估是否有转移性感染。对于万古霉素 MIC 升高的分离株引起的感染，以及不良反应发生率较高的患者，应考虑替代抗生素治疗。
