Optimizing blood culture diagnostics through laboratory automation: reducing turnaround time and improving clinical outcomes

Bloodstream infections pose significant clinical challenges, requiring rapid and accurate diagnostics to guide timely antimicrobial therapy. Although efforts to reduce turnaround time (TAT) have focused on emerging molecular techniques and rapid antimicrobial susceptibility testing (AST) methods, these innovations currently complement rather than replace standard protocols. To balance innovation with reliability, we investigated the impact of integrating laboratory automation into the blood culture diagnostic workflow while preserving conventional pathogen identification via mass spectrometry and AST. In this single-center, prospective study, we compared key performance indicators between a historical cohort (March-August 2023; 192 episodes, 110 patients) and an intervention cohort (March-August 2024; 156 episodes, 112 patients) utilizing an automated workflow with the BacT/Alert Virtuo BC system, VPlus 50 automated sample processor, and Vitek 2 XL Microbiology Analyzer. The optimized workflow included automated loading and unloading of blood culture bottles, automatic subculturing of positive cultures, expert system-based review of AST results, and automated reporting of negative results. Post-optimization, the time from blood culture collection to final report was significantly reduced from 95.99 h (79.29-117.63) to 60.81 h (47.06-82.38), with a more pronounced reduction for gram-negative bacteria (44.87 h) compared with gram-positive bacteria (27.24 h). Although the 28-day mortality rate remained unchanged, patients in the post-optimization group experienced significantly shorter hospital stays, faster achievement of optimal therapy, and lower costs related to antibiotics, laboratory tests, and overall hospitalization. These findings indicate that integrating automation in blood culture diagnostics enhances laboratory efficiency, improves clinical outcomes, and reduces healthcare costs, supporting its broader implementation in clinical microbiology.IMPORTANCEBloodstream infections require prompt and accurate diagnosis to enable timely, targeted antimicrobial therapy. Traditional blood culture workflows are often hindered by labor-intensive processes and limited after-hours capacity, delaying critical clinical decisions. This study demonstrates that integrating laboratory automation, including automated loading and unloading of blood culture bottles, automatic subculturing of positive cultures, expert system-based review of antimicrobial susceptibility results, and automated reporting of negative results can significantly reduce diagnostic turnaround time without additional staffing. Implemented in a high-volume tertiary hospital, the optimized workflow led to faster initiation of optimal therapy, shorter hospital stays, and reduced healthcare costs, particularly for gram-negative bacteremia. These findings highlight how automation enhances both laboratory efficiency and patient outcomes, supporting its broader adoption in modern clinical microbiology.