Abstract

Staphylococcus aureus ( S. aureus ) is a versatile and virulent pathogen and has become one of the leading causes of life-threatening bloodstream infections, such as sepsis and endocarditis. The morbidity and mortality of S. aureus bacteremia remain high in recent years. Rapid identification of S. aureus can lead to faster initiation of appropriate antibiotic treatment, thereby reducing treatment costs and mortality. Blood culture is the gold standard for diagnosing bacteremia, but it is time-consuming and poorly sensitive. Herein, vancomycin modified magnetic nanoparticles (VMPs) and separation glue were introduced to enrich S. aureus in blood in a direct and convenient manner, and then the bacteria were detected by droplet digital PCR (ddPCR). The nanoparticle-based culture-free method can concentrate and detect S. aureus from whole blood within 3 h, significantly shortening the detection time compared with the traditional culture method (3–5 days). The limit of detection of this approach for S. aureus was as low as 10 CFU/mL, which significantly improved the diagnostic rate in blood bacteremia. The developed VMPs-ddPCR strategy could be a promising tool for identifying S. aureus , guiding treatment decisions in the early stages of bloodstream infections, and predicting efficacy and thereby reducing mortality.