ASM 2024

Rapid AST is here to stay: Multi-site comparison of performance and time-to-results of rapid and legacy AST Systems with “gold standard” methods.

Speakers: Dr. Patricia (Trish) Simner, Johns Hopkins PhD, D(ABMM), Dr. Andrew Clark, UTSW, PhD, D(ABMM),  Dr. John Fissel, TriCore Reference Laboratories
Ph.D. D(ABMM), M(ASCP)CM

Summary: Antimicrobial susceptibility testing (AST) has been routinely used to guide Abx treatment. Recently, the newly developed rapid AST platforms have substantially decreased time-to-result for AST, allowing faster actionable results for the treating physician. However, due to cost, complexity, and the need for a reference Broth Microdilution Method (BMD) methodology, data benchmarking for these platforms’ performance is lacking.

This study is the first to compare the clinical performance of the Vitek 2, MicroScan, Phoenix, Selux, and Kirby Bauer methods against the triplicate reference Broth Microdilution Method (BMD) using approximately 600 banked isolates and CDC-AR bank samples at multiple clinical laboratories in the US. The clinical accuracy and time-to-results are calculated for each system. The data demonstrates the systems’ performance under field conditions and points to areas for attention when relying on the results for the platforms to guide Abx treatment.