Impact on the Proper Use of Antimicrobials for Patients with Gram-negative Bacteremia due to a Change in Testing Location of Positive Blood Culture Specimens

A general hospital with approximately 600 beds and specializing in providing advanced medical care in a suburban area traditionally sent blood specimens to a central laboratory located in another prefecture for bacteriological testing. This process delayed the timely intervention of the antimicrobial stewardship team (AST) in positive blood culture cases due to the extended time required to report the test results. In 2022, the hospital transitioned to conducting blood tests at a laboratory adjacent to the facility, allowing for immediate reporting of results and enabling the AST to intervene more rapidly. This study aims to assess the impact of reduced reporting times on the management of positive blood culture specimens. In 2021, 92 cases were tested at the headquarters’ laboratory, while in 2022, 65 cases were tested at the nearby laboratory. The transition to the nearby laboratory in 2022 resulted in a turnaround time reduction for reporting the blood culture results to 1 day. Although there were no significant differences in the hospitalization duration, duration of the antimicrobial agent administration, or use of broad-spectrum antimicrobial agents, the time to de-escalation was significantly shortened by 2 days in 2022 (P < 0.004). This reduction in time to de-escalation, which is facilitated by quicker reporting, underscores the importance of localizing laboratory services to enhance timely and appropriate antimicrobial administration. The findings highlight the critical need for continued improvements in the laboratory testing system, particularly in comprehensive hospitals like this, where timely diagnostics are essential for optimal patient outcomes and effective antimicrobial stewardship.