Dey S, Gudipati S, Giuliano C, Zervos MJ, Monk JM, Szubin R, Jorgensen SCJ, Sakoulas G, and Berti AD. Reduced production of bacterial membrane vesicles predicts mortality in ST45/USA600 methicillin-resistant Staphylococcus aureus bacteremia. Antibiotics 2020; 9(1).
Immune biomarkers can stratify mortality risk in staphylococcal bacteremia. Microbial biomarkers may provide more consistent signals during early infection. We demonstrate that in ST45/USA600 bacteremia, bacterial membrane vesicle production in vitro predicts clinical mortality (773 vs. 116 RFU, survivors vs. decedents, p < 0.0001). Using a threshold of 301 relative fluorescence units (RFU), the sensitivity and specificity of the membrane vesicles to predict mortality are 78% and 90%, respectively. This platform is facile, scalable and can be integrated into clinical microbiology lab workflows.