Development and standardization of simple, timely, and cost-effective antibiotic susceptibility assays are much needed to address the emergence of global resistance. The use of matrix-assisted laser desorption/ionization time of flight mass spectrometry is routine for bacterial identification. This study evaluated 2 assays using the VITEK MS for rapid detection and accurate differentiation of bacterial antibiotic susceptibility. We describe an extraction method and direct-on-target microdroplet growth assay (DOT-MGA). Non‐susceptible and susceptible strains of Staphylococcus aureus, Enterococcus species, Escherichia coli, and Klebsiella pneumoniae were tested. The liquid extraction method and DOT-MGA proved to be reliable assays providing consistent differentiation between non‐susceptible and susceptible strains. Results from this study support VITEK MS and these assays as rapid and accurate tools to augment traditional susceptibility testing. If implemented clinically, these assays can reduce the cost of patient care and the time to deliver critically needed treatment.

为了解决全球耐药性的出现，非常需要开发，标准化简单，及时且具有成本效益的抗生素药敏试验。通常使用基质辅助激光解吸/电离飞行时间质谱进行细菌鉴定。这项研究使用VITEK MS评估了2种测定法，用于快速检测和准确区分细菌性抗生素敏感性。我们描述了一种提取方法和直接针对目标的微滴生长测定（DOT-MGA）。非敏感和易感的金黄色葡萄球菌，肠球菌，大肠杆菌和肺炎克雷伯菌菌株经过测试。液体提取方法和DOT-MGA被证明是可靠的检测方法，可在不敏感和敏感菌株之间提供一致的区分。这项研究的结果支持VITEK MS和这些测定法，作为增强传统药敏试验的快速准确的工具。如果在临床上实施，这些测定法可以减少患者护理的成本，并减少提供急需治疗的时间。