Al Sidairi Hilal, Reid Emma K, LeBlanc Jason J, Sandila Navjot, Head Joline, Davis Ian, Bonnar Paul
Division of Infectious Diseases, Department of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada.
Division of Microbiology, Department of Pathology and Laboratory Medicine, Nova Scotia Health, Halifax, Nova Scotia, Canada.
Microbiol Spectr. 2023 Feb 15;11(2):e0164822. doi: 10.1128/spectrum.01648-22.
Pending antibiotic susceptibility results, vancomycin is often used for bloodstream infections (BSIs) to ensure treatment of methicillin-resistant Staphylococcus aureus (MRSA). As rapid discrimination of methicillin-susceptible S. aureus (MSSA) from MRSA in BSIs could decrease vancomycin use and allow early optimization of beta-lactam therapy, this study evaluated the impact of the use of rapid molecular testing for MSSA and MRSA coupled with an antimicrobial stewardship program (ASP) intervention. Between January and July 2020, the Cepheid Xpert MRSA/SA blood culture assay was performed on blood cultures with Gram-positive cocci in clusters that were identified as S. aureus using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The ASP team member then consulted with the treating physician. The time to optimal therapy (TTOT) and clinical outcomes, including length of hospital stay (LOS), were compared between the intervention ( = 29) and historical ( = 27) cohorts. TTOT was defined as the time from the first blood culture draw to the use of appropriately dosed antistaphylococcal beta-lactam monotherapy without vancomycin. Molecular testing significantly reduced the median time to MSSA and MRSA discrimination to 7.8 h, compared to 24.3 h with culture-based methods (0.001). Compared to the control group, the median TTOT in the ASP intervention group was significantly shorter (0.041) at 38.0 h (versus 50.1 h). Rapid discrimination between MRSA and MSSA using molecular testing, paired with an ASP intervention, significantly reduced the TTOT in patients with MSSA BSIs. Our research shows that time to optimal antibiotic treatment for serious bloodstream infections can be improved with rapid molecular sensitivity testing and feedback to prescribers. This can be implemented in laboratories without full microbiology services or training to improve patient outcomes by improving antimicrobial use.
在抗生素敏感性结果出来之前，万古霉素常用于治疗血流感染（BSI），以确保对耐甲氧西林金黄色葡萄球菌（MRSA）进行治疗。由于在血流感染中快速区分甲氧西林敏感金黄色葡萄球菌（MSSA）和MRSA可以减少万古霉素的使用，并允许早期优化β-内酰胺类治疗，本研究评估了使用快速分子检测区分MSSA和MRSA并结合抗菌药物管理计划（ASP）干预的影响。2020年1月至7月期间，对使用基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）鉴定为金黄色葡萄球菌的革兰氏阳性球菌簇血培养物进行了赛沛Xpert MRSA/SA血培养检测。然后，ASP团队成员与主治医生进行了会诊。比较了干预组（n = 29）和历史队列组（n = 27）的最佳治疗时间（TTOT）和临床结局，包括住院时间（LOS）。TTOT定义为从首次采集血培养物到使用适当剂量的抗葡萄球菌β-内酰胺单药治疗且不使用万古霉素的时间。与基于培养的方法相比，分子检测显著缩短了区分MSSA和MRSA的中位时间，分别为7.8小时和24.3小时（P = 0.001）。与对照组相比，ASP干预组的中位TTOT显著缩短（P = 0.041），为38.0小时（而对照组为50.1小时）。使用分子检测快速区分MRSA和MSSA，并结合ASP干预，显著缩短了MSSA血流感染患者的TTOT。我们的研究表明，通过快速分子敏感性检测和向开处方者反馈，可以改善严重血流感染的最佳抗生素治疗时间。这可以在没有完整微生物学服务或培训的实验室中实施，以通过改善抗菌药物使用来改善患者结局。
