Comparison of conventional susceptibility testing, penicillin-binding protein 2a latex agglutination testing, and mecA real-time PCR for detection of oxacillin resistance in Staphylococcus aureus and coagulase-negative Staphylococcus.

Penicillin-binding protein (PBP) 2a latex agglutination was compared with conventional susceptibility testing and mecA real-time PCR for the detection of oxacillin resistance in Staphylococcus aureus. Inoculum volume and induction with oxacillin were PBP 2a testing variables. For coagulase-negative Staphylococcus, an increased inoculum volume of 10 microl greatly reduced the number of isolates requiring induction.