Rapid molecular diagnostics for antimicrobial-resistant bacterial infections: impact on time to effective antibiotic therapy and clinical outcomes
DOI:
https://doi.org/10.66687/jebmr.2.1.2026.6Keywords:
molecular diagnosticsAbstract
Background: Resistant bacterial infections require timely effective therapy, yet conventional organism identification and antimicrobial susceptibility testing may delay treatment modification. We compared rapid molecular diagnostics with conventional pathways in a multicentre observational cohort.
Methods: The de-identified dataset comprised 520 adults with confirmed resistant bacterial infections from eight hospitals, including 259 managed via rapid testing and 261 via conventional methods. Clinical suspicion was time zero. The primary treatment-timing analysis focused on patients not already receiving effective empirical antibiotics. Secondary outcomes included actionable-result time, antimicrobial stewardship review, active therapy within 24 hours, 30-day mortality, clinical cure and hospital stay. Multivariable models adjusted for baseline case mix, resistance phenotype and hospital.
Results: The median time to actionable results was 8.8 versus 61.7 hours, respectively. Among 358 patients initially without active therapy, 181 rapid-test patients and 177 controls were at risk; effective therapy was ultimately initiated in 181 and 174, respectively. Median time to active therapy among recipients was 17.2 versus 69.5 hours (difference −52.3 hours; bootstrap 95% CI −58.4 to −47.4). Therapy by 24 hours occurred in 162/181 (89.5%) versus 0/177 (0%). In the total cohort, 30-day mortality was 10.4% versus 7.3%; adjusted odds ratio (aOR) 1.21 (95% CI 0.62–2.33). Clinical cure occurred in 72.2% versus 69.3% (aOR 1.28, 95% CI 0.86–1.92).
Conclusions: Rapid testing was associated with substantially earlier actionable microbiology and active treatment in patients lacking effective initial coverage. No statistically established improvement in survival, cure or length of stay was observed. The non-randomised design and near-complete timing separation require cautious interpretation.
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