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-resistani Staphylococcus aureus in ≤6 h: (i) a nitrate reductase assay and (ii) a resazurin microplate method. MICs agreed with results obtained by CLSI 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. Copyright © 2006, American Society for Microbiology. All Rights Reserved.