College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87106, USA.
J Antimicrob Chemother. 2011 Oct;66(10):2386-92. doi: 10.1093/jac/dkr301. Epub 2011 Jul 20.
Therapeutic use of vancomycin is characterized by decreased susceptibilities and increasing reports of clinical failures. Few studies have examined the clinical outcomes of patients with methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia treated with vancomycin. The primary objective was to compare clinical outcomes of patients with MRSA bacteraemia treated according to standard of care practices.
Patients were included if: (i) admitted to University of New Mexico Hospital between 2002 and 2009; (ii) ≥18 years of age; (iii) had one blood culture positive for MRSA; and (iv) received vancomycin. Clinical outcomes were defined as cure, failure (relapse of infection 30 days after completion of therapy, death or change in therapy) or unevaluable. Patient demographics, source of bacteraemia, treatment regimen, and microbiological characteristics were determined.
Two hundred patients with MRSA bacteraemia were included. Sixty-one patients were unevaluable, leaving 139 patients for the final analysis. Seventy-two (51.8%) patients were cured and 67 (48.2%) experienced vancomycin failure. Vancomycin MIC(90) was 2 mg/L for both groups by Etest. Patients with endocarditis (P = 0.02) or pneumonia (P = 0.02) were more likely to fail therapy. Panton-Valentine leucocidin, loss of agr functionality and strain type were not predictors of outcomes in this study.
High failure rates were observed in patients with MRSA bacteraemia treated with vancomycin, despite high vancomycin troughs and low rates of nephrotoxicity. Predictors of vancomycin failure included endocarditis and pneumonia. In these situations, vancomycin provides suboptimal therapy.
万古霉素的治疗用途具有较低的敏感性和越来越多的临床失败报告。很少有研究检查过耐甲氧西林金黄色葡萄球菌（MRSA）菌血症患者用万古霉素治疗的临床结果。主要目的是比较根据标准护理实践治疗的 MRSA 菌血症患者的临床结果。
如果符合以下条件，则将患者纳入研究：（i）2002 年至 2009 年期间入住新墨西哥大学医院；（ii）≥18 岁；（iii）有一份血培养为 MRSA 阳性；且（iv）接受了万古霉素治疗。临床结果定义为治愈、失败（治疗完成后 30 天内感染复发、死亡或治疗改变）或无法评估。确定了患者的人口统计学、菌血症来源、治疗方案和微生物学特征。
共纳入 200 例 MRSA 菌血症患者。61 例患者无法评估，最终分析中留下 139 例患者。72 例（51.8%）患者治愈，67 例（48.2%）患者万古霉素治疗失败。Etest 法显示两组万古霉素 MIC（90）均为 2 mg/L。患有心内膜炎（P=0.02）或肺炎（P=0.02）的患者更有可能治疗失败。本研究中，Panton-Valentine 白细胞溶解素、agr 功能丧失和菌株类型不是结局的预测因素。
尽管万古霉素谷浓度高且肾毒性发生率低，但用万古霉素治疗的 MRSA 菌血症患者仍观察到高失败率。万古霉素失败的预测因素包括心内膜炎和肺炎。在这些情况下，万古霉素提供的治疗效果不佳。
