Introduction This study aimed to investigate whether droplet digital polymerase chain reaction (ddPCR) assay can be integrated with antimicrobial stewardship for rapid diagnosis to improve clinical outcomes in patients with suspected bloodstream infections (BSIs). We also explored whether combining ddPCR assay with procalcitonin (PCT) could better guide antibiotic discontinuation in patients with suspected BSIs. Methods This prospective observational study was conducted in Zhejiang Provincial People’s Hospital from April 2019 to October 2023. Antimicrobial drug combinations were categorized as appropriate or inappropriate based on the findings of the ddPCR assay. Propensity score matching (PSM) was conducted to address possible confounding variables. The primary outcome was 28-day all-cause mortality. Results A total of 703 patients were evaluated for the consistency of pathogens detected by ddPCR with those covered by the initial antibiotic regimen (IAR). Among these patients, 355 received appropriate IAR, 256 were adjusted for inappropriate IAR, and 92 were unadjusted for inappropriate IAR. A significant difference in 28-day mortality among the three cohorts was observed before and after PSM (P ≤ 0.002). Multivariate Cox regression analysis showed that IAR adjustment [inappropriate IAR unadjusted as reference, appropriate IAR: hazard ratio (HR) = 0.47; P 7 days of antibiotic therapy and antibiotic discontinuation, the 28-day mortality using the ddPCR assay combined with PCT-guided antibiotic discontinuation was significantly lower (12.0 vs. 37.3 vs. 39.6%; P < 0.001) than that of those guided by ddPCR assay or PCT alone. Conclusions Integrating a ddPCR assay for rapid diagnosis with antibiotic stewardship could improve the prognosis in patients with BSIs, not only by guiding antibiotic regimen adjustment but also by making decisions on antibiotic discontinuation in conjunction with PCT. Trial Registration ChiCTR, ChiCTR2600116655.
Shao et al. (2026) studied this question.