Enhancing Blood Culture Diagnostics in PaLM Microbiology Lab: Efficiency, Education, and Research Integration
Sepsis is a medical emergency in which every hour of delayed appropriate therapy significantly increases mortality. Rapid and accurate microbiological diagnosis is central to guiding effective antimicrobial treatment. Blood cultures remain the gold standard for identifying bloodstream infections. Improving laboratory turnaround time for both organism identification and antimicrobial susceptibility testing is therefore critically important for improving patient outcomes and reducing sepsis-related mortality.
In response to this clinical need, our microbiology laboratory has undertaken a series of diagnostic improvement initiatives aimed at accelerating blood culture workflows, increase capacity, and supporting timely clinical decision-making.
Last year, we shared an update on a quality improvement initiative in our microbiology lab focused on shortening the standard five-day blood culture incubation period to four days. This change, implemented after an extensive review of over 70,000 cultures from the previous year, demonstrated that more than 99% of clinically relevant positives were detected within four days, with an average time to positivity of just 23 hours. Post-implementation monitoring confirmed that diagnostic performance was maintained, and unnecessary workups for contaminants were reduced. The results of this project, led by Dr. Fatimah AlMutawa, a medical microbiologist, were recently published and provide clear evidence supporting the clinical validity and operational advantages of this change.
To continue advancing blood culture diagnostics and the management of sepsis, we have piloted a second phase of improvement: direct identification and antimicrobial susceptibility testing from positive blood cultures. While commercially available kits exist, we evaluated a lab-developed method without the associated cost burden—an approach more sustainable for routine use. I’m pleased to share that preliminary data show high agreement with conventional methods: 95.5% for organism identification with no misidentifications, and 98% for antimicrobial susceptibility testing. This workflow has the potential to shorten AST turnaround time by 24–48 hours, allowing for earlier clinical interventions and improved patient outcomes.
A particularly meaningful milestone in this project was the return of student involvement to the microbiology lab for the first time since the COVID-19 pandemic. A Medical Sciences student joined our team and was actively involved in bench-level testing, data collection, and analysis. Their participation contributed significantly to the project and helped re-establish the lab as a space for learning and academic collaboration.
We are now preparing a manuscript to share our findings and will be exploring how this workflow can be integrated into routine practice.
In parallel, a new Collaborative Research and Innovation Fund (CRIF) grant between Dr. Fatimah AlMutawa and Dr. Zia Khan has been awarded effective August 1, 2025. This funded study will explore the role of cell-free long non-coding RNAs in bloodstream infections by comparing patients with positive and negative blood cultures and stratifying them by sepsis severity. As part of this initiative, students will also be involved in laboratory work, with plans to begin participation in the fall. This work bridges clinical microbiology with molecular biology and reflects the growing opportunities for cross-disciplinary research within our department.
These combined efforts are helping to bring our lab up to speed with innovation and academic engagement. They also reflect our commitment to supporting student learning and nourishing research through meaningful, hands-on projects that connect clinical service with scientific discovery.
