Evaluation of BD Phoenix and Microscan WalkAway for determination of fosfomycin susceptibility in Staphylococcus aureus

We evaluate the performance of BD Phoenix (BD Diagnostic; Hunt Valley, MD) and MiscroScan WalkAway (Beckman Coulter Inc; Carlsbad, CA) systems versus reference agar dilution method for fosfomycin susceptibility determination in 200 Staphylococcus aureus clinical isolates. Both methods exhibit ≤89.0% of categorica agreement and ≥63.3% of very major error. All commercial antimicrobial susceptibility systems show poor concordance with reference method.