Rapid BCID panels: Enabling antimicrobial stewardship in the treatment of bloodstream infections

• Bloodstream infections are a critical healthcare concern, leading to mortality rates of up to 40%
• Researchers showed that rapid molecular blood culture identification (BCID) panels have the potential to identify infectious organisms faster than conventional microbiology tests
• Quicker identification of pathogens and selected resistance genes could enable earlier and more appropriate clinical intervention, promoting diagnostic and antimicrobial stewardship

Antimicrobial stewardship focuses on optimizing antimicrobial use to improve patient outcomes while limiting the emergence of antimicrobial resistance (AMR), but successful stewardship begins long before an antimicrobial is prescribed. Diagnostic stewardship, which is the coordinated effort to optimize the selection, performance, and interpretation of diagnostic tests, works hand in hand with antimicrobial stewardship to guide clinical decision-making. These complementary strategies allow laboratories and physicians to identify pathogens more rapidly, optimize antimicrobial therapy, and help curb AMR.

Rapid molecular blood culture identification (BCID) panels are becoming an increasingly critical tool in this effort through rapid detection of pathogens and select antimicrobial resistance markers. These assays can provide actionable results hours before conventional microbiology methods are complete, helping healthcare teams make earlier, more targeted antimicrobial treatment decisions.¹

The importance of diagnostic and antimicrobial stewardship is especially evident in the management of bloodstream infections. These infections carry mortality rates of 10-40%, and studies have shown that delays in administering appropriate antimicrobial therapy is associated with a decrease in survival.^2-5

To avoid treatment delays, clinicians typically initiate immediate treatment with empiric broad-spectrum antibiotics while awaiting pathogen identification with blood cultures, which could take up to 5 days, plus an additional 1 to 2 days for antibiotic susceptibility testing (AST) results.^6,7 While often necessary, this lengthy approach increases the risk of toxicity, additional infections, AMR, and longer hospital stays. 

At a webinar this year, part of a three-part series focused on diagnostic and antimicrobial stewardship, “Rapid pathogen identification with molecular BCID panels: Implications for the clinical management of bloodstream infections,” Dr. Ir. Sien De Koster and Dr. Thomas Demuyser shared insights into implementing rapid molecular technologies and their potential on patient care, diagnostics, and antimicrobial stewardship.

To evaluate how rapid molecular testing could impact result turnaround times and improve lab efficiency, researchers at Antwerp University Hospital compared a rapid molecular testing system and BCID panels to conventional microbiology tests. Rapid molecular BCID panels enable detection of a broad range of bloodstream pathogens and selected resistance genes directly from positive blood cultures in about 90 minutes. In the study, patients with positive blood cultures underwent typical standard of care microbiological testing for positive blood cultures, including Gram staining, Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF) for organism identification and AST, while the BCID panels were performed in parallel.

Results of the study demonstrated strong analytical performance, with the BCID panels showing high agreement with conventional culture methods, including 100% concordance for gram-positive organisms and antimicrobial resistance gene detection concordance with AST. 

Most importantly, the study highlighted the value of faster turnaround times with the rapid molecular diagnostic system. Following blood culture positivity, Gram stain results were available in a median of 3.8 hours, molecular BCID results in 7.4 hours, MALDI-TOF identification in 12.7 hours and standardized AST in nearly 32 hours. “In case a resistance gene is detected, you will know this much sooner compared to the antibiotic susceptibility testing,” commented Dr. De Koster.

Furthermore, technicians positively reported on using the rapid molecular system and BCID panels. “Overall, the system was user-friendly. They found the system easy to use with clear software, limited hands-on time, fast, intuitive, and with clear reporting,” Dr. De Koster added.

By identifying pathogens and selected resistance genes hours or even a full day ahead of other methods, rapid molecular diagnostic testing may enable earlier clinical intervention. “These have a turnaround time of hours, and in combination with an active antimicrobial stewardship, this could lead to an effective therapy for the patients in a more timely manner,” said Dr. De Koster. “The system could improve the microbiology workflow.”

The greatest value of rapid molecular testing is giving clinicians more information for antimicrobial treatment decisions. “First and foremost, we want to treat a patient with the correct antibiotic that is effective against the pathogen involved,” said Dr. Demuyser. “Secondly, we also want to have the most narrow spectrum possible.”

Clinical microbiologists are central to this process, providing treatment recommendations based on Gram stain results, MALDI-TOF identification, and AST. According to Dr. Demuyser, these results help physicians determine whether to de-escalate to a narrower-spectrum antibiotic, escalate therapy when resistance is detected, or prescribe combination therapy when clinically appropriate.

In the Antwerp cohort, the median time to optimal antimicrobial therapy was 36 hours after blood culture positivity, approximately 48 hours after empiric antibiotics were initiated. In a retrospective hypothetical analysis, rapid identification with BCID panels showed the greatest potential clinical impact in gram-positive and mixed infections, where it could reduce the time to effective antimicrobial therapy and support narrower-spectrum antibiotics, according to Dr. Demuyser. 

“Rapid molecular testing for bloodstream infections offers some technical advantages, including automation and reduced hands-on time,” said Dr. Demuyser. The preliminary hypothetical analysis also points to meaningful clinical applicability for Antwerp with rapid BCID panels, “especially in reduction in time to optimal and more narrow spectrum antibiotics.”

Bloodstream infections remain a time-critical medical emergency. This makes rapid diagnostic information increasingly important to patient care. Growing evidence suggests that rapid molecular BCID panels can improve laboratory workflow efficiency, supporting earlier antimicrobial optimization through faster pathogen identification and antimicrobial resistance gene detection. 

Conventional culture methods remain the standard of care for pathogen identification. However, healthcare organizations have the opportunity to integrate rapid molecular diagnostics into existing microbiology workflows to support faster, more informed treatment decisions so patients get the right treatment at the right time.

At the conclusion of the webinar, Dr. Demuyser noted that additional findings are expected as the Antwerp University Hospital study progresses, including data from the interventional cohort and other clinical outcomes such as hospital length of stay, ICU length of stay, 30-day readmission, and 30-day all-cause mortality.

“The potential impact of rapid ID through molecular testing can have an impact on the correct antibiotic stewardship,” said Dr. Demuyser.