Preliminary Single-Center Evaluation of the Alifax Molecular Mouse Sepsis Panel for Rapid Detection of Bloodstream Pathogens.

Background/

Objectives

We evaluated the diagnostic performance of the Alifax Molecular Mouse (MM) sepsis panel for rapidly directly detecting pathogens and resistance genes in positive blood culture broths.

Methods

In this prospective single-center study, 40 positive blood culture specimens were analyzed using four MM cartridges targeting Gram-positive and -negative bacteria and major antimicrobial resistance genes. The results were compared with those obtained using the routine microbiological protocol, including organism identification using the MALDI Biotyper system and antimicrobial susceptibility testing using the VITEK 2 and MicroScan WalkAway systems. Additionally, the MM panel results were compared with those obtained using the FilmArray BCID2.

Results

Compared with the routine protocol, the MM panel achieved a positive percent agreement (PPA) of 89.5% (34/38; 95% confidence interval [CI], 75.9-95.8%) for bacterial identification, indicating moderate-to-good diagnostic performance. For antimicrobial resistance gene detection, the PPA was 92.1% (35/38; 95% CI, 79.2-97.3%). Compared with the FilmArray BCID2, the overall agreement of the MM panel was 89.4% (34/38) for bacterial identification and 84.2% (32/38) for antimicrobial resistance gene detection. The MM panel generated clinically actionable results within 1 h (mean turnaround time, 55.5 min; 95% CI, 55.1-55.9 min), substantially reducing the turnaround time compared with the conventional microbiological workflow, which requires 1.5-2 days for subculture and automated antimicrobial susceptibility testing.

Conclusions

The MM sepsis panel enabled rapid, direct identification of bloodstream pathogens and key antimicrobial resistance markers from positive blood cultures, substantially reducing turnaround time and exhibiting its potential as an adjunct to routine microbiological workflows.