Two new colorimetric methods for early detection of vancomycin and oxacillin resistance in Staphylococcus aureus

Abstract

We developed two colorimetric methods for the detection of vancomycin- and oxacillin-resistant Staphylococcus aureus in <= 6 h: (i) a nitrate reductase assay and (ii) a resazurin microplate method. MICs agreed with results obtained by CLI methods for oxacillin. However, detection of vancomycin resistance required a larger inoculum. These methods may be recommended for the detection of vancomycin- and oxacillin-resistant S. aureus.