Park Dong Jin M, Wu Tianqi, Chen Liben, Lee Pei-Wei, Hsieh Kuangwen, Wang Tza-Huei
Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA.
Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA.
Sci Rep. 2025 Jul 9;15(1):24766. doi: 10.1038/s41598-025-08987-z.
Bloodstream infections (BSI) caused by pathogenic bacteria are a global health threat, highlighting the need for improved diagnostic methods. Current methods, such as mass spectrometry, depend on time-consuming blood cultures, which hinder timely diagnosis. Nucleic acid amplification tests (NAATs) offer potential for sensitive bacteria detection but are bottlenecked by the inability to isolate bacteria at low concentrations from blood. This study introduces a facile dual filter workflow for isolating low concentrations of bacteria from blood without blood culture. The workflow, which involves blood dilution and osmolysis, blood cell filtration, chemical and enzymatic lysis, and filter-based bacteria capture, can be completed in ~ 30 min without special equipment. It readily combines with downstream broad-based bacteria detection via PCR and high-resolution melt (HRM), as well as pheno-molecular antimicrobial susceptibility testing (AST) via PCR. When coupled with species-specific PCR, ~ 10 CFU of bacteria in 0.5 mL of blood could be detected. The small sample volume is particularly attractive because it is comparable to those obtained from fingerstick collections or pediatric patients. With further optimization, testing with a wider range of bacteria, and integration with rapid point-of-care testing, this simple dual filter workflow can be a key driver for advancing blood culture-free bacterial BSI diagnosis, especially in resource-limited settings.
由致病细菌引起的血流感染（BSI）是一种全球健康威胁，凸显了改进诊断方法的必要性。目前的方法，如质谱分析，依赖耗时的血培养，这阻碍了及时诊断。核酸扩增试验（NAATs）为灵敏检测细菌提供了潜力，但因无法从血液中低浓度分离细菌而受到限制。本研究介绍了一种简便的双重过滤流程，用于在不进行血培养的情况下从血液中分离低浓度细菌。该流程包括血液稀释和渗透溶解、血细胞过滤、化学和酶解以及基于过滤的细菌捕获，无需特殊设备，约30分钟即可完成。它可轻松与下游基于PCR的广谱细菌检测和高分辨率熔解（HRM）以及基于PCR的表型分子抗菌药敏试验（AST）相结合。与物种特异性PCR结合时，可检测到0.5 mL血液中约10 CFU的细菌。小样本量特别有吸引力，因为它与手指采血或儿科患者获得的样本量相当。通过进一步优化、对更广泛细菌的检测以及与快速即时检测的整合，这种简单的双重过滤流程可以成为推动无血培养细菌BSI诊断的关键驱动力，尤其是在资源有限的环境中。
