College of Medicine, Chang Gung University, 333, Taoyuan, Taiwan.
Division of Infectious Diseases, Department of Internal Medicine, Chang Gung Memorial Hospital, 333, Taoyuan, Taiwan.
Sci Rep. 2018 May 18;8(1):7868. doi: 10.1038/s41598-018-26277-9.
Bacteremia caused by MRSA with reduced vancomycin susceptibility (MRSA-RVS) frequently resulted in treatment failure and mortality. The relation of bacterial factors and unfavorable outcomes remains controversial. We retrospectively reviewed clinical data of patients with bacteremia caused by MRSA with vancomycin MIC = 2 mg/L from 2009 to 2012. The significance of bacterial genotypes, agr function and heterogeneous vancomycin-intermediate S. aureus (hIVSA) phenotype in predicting outcomes were determined after clinical covariates adjustment with multivariate analysis. A total of 147 patients with mean age of 63.5 (±18.1) years were included. Seventy-nine (53.7%) patients failed treatment. Forty-seven (31.9%) patients died within 30 days of onset of MRSA bacteremia. The Charlson index, Pitt bacteremia score and definitive antibiotic regimen were independent factors significantly associated with either treatment failure or mortality. The hVISA phenotype was a potential risk factor predicting treatment failure (adjusted odds ratio 2.420, 95% confidence interval 0.946-6.191, P = 0.0652). No bacterial factors were significantly associated with 30-day mortality. In conclusion, the comorbidities, disease severity and antibiotic regimen remained the most relevant factors predicting treatment failure and 30-day mortality in patients with MRSA-RVS bacteremia. hIVSA phenotype was the only bacterial factor potentially associated with unfavorable outcome in this cohort.
耐万古霉素金黄色葡萄球菌（MRSA-RVS）引起的菌血症常导致治疗失败和死亡。细菌因素与不良结局的关系仍存在争议。我们回顾性分析了 2009 年至 2012 年期间万古霉素 MIC=2mg/L 的耐甲氧西林金黄色葡萄球菌（MRSA）菌血症患者的临床资料。在进行多变量分析以调整临床协变量后，确定了细菌基因型、agr 功能和异质性万古霉素中介金黄色葡萄球菌（hIVSA）表型对预测结局的意义。共纳入 147 例平均年龄为 63.5（±18.1）岁的患者。79 例（53.7%）患者治疗失败。47 例（31.9%）患者在 MRSA 菌血症发病后 30 天内死亡。Charlson 指数、Pitt 菌血症评分和明确的抗生素方案是与治疗失败或死亡率相关的独立因素。hVISA 表型是预测治疗失败的潜在危险因素（调整优势比 2.420，95%置信区间 0.946-6.191，P=0.0652）。没有细菌因素与 30 天死亡率显著相关。总之，合并症、疾病严重程度和抗生素方案仍然是预测 MRSA-RVS 菌血症患者治疗失败和 30 天死亡率的最重要因素。在该队列中，hIVSA 表型是唯一与不良结局相关的细菌因素。
