Performance comparison and clinical validation of two rapid direct identification and antimicrobial susceptibility testing approaches for pathogens isolated from positive blood cultures in children

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• Picked for Pediatrics and Child Health (paper of the day, 7 October 2026): Rapid species ID and AST from positive blood cultures in

Abstract

OBJECTIVE: Rapid species identification and antimicrobial susceptibility testing (AST) for bloodstream infections (BSIs) are critical for timely and targeted therapy. This study evaluated the clinical performance of two rapid methods (HBL rapid method and rapid method with short-term culture) against the routine standard blood culture (BC) method. METHODS: A total of 162 monobacterial BC samples were enrolled. These samples were processed either using the HBL system (subcultured within 2 hours) or incubated on agar plates for short-term culture (6-8 hours). Subsequent species identification and AST were also performed. Essential agreement (EA), categorical agreement (CA), and error rates were calculated as compared to the conventional method. RESULTS: Among 162 isolates, Gram-negative bacteria comprised 66.7% (108/162) of the isolates, predominantly Enterobacteriales. Both the rapid methods demonstrated 100% species identification concordance with the standard BC method. In terms of AST, using the standard AST result as reference, the HBL rapid method yielded an EA of 95.6% and a CA of 98.3%, with minor error (mE), major error (ME), very major error (VME), and bias rates of 1.1%, 0.4%, 0.1%, and -2.3%, respectively. Similarly, the rapid method with short-term culture showed comparable efficacy (EA, 96.5%; CA, 98.8%; mE, 1.0%; ME, 0.2%; VME, 0.1%; bias, -0.3%). Crucially, the mean turnaround times (TATs) for the HBL rapid method (44.7 hours) and the rapid method with short-term culture (45.9 hours) were significantly shorter than the standard method (68.4 hours), representing an approximate 24-hour reduction in BC workflow. CONCLUSIONS: The two rapid methods exhibit exceptional accuracy and reliability for species identification and AST directly from positive blood cultures, which can significantly shorten the TAT for BSI diagnosis, offering clinicians to optimize timely and appropriate clinical treatment.

Abstract as published, via PubMed.