Are any modifications required of routine disk diffusion and MIC methods when testing vancomycin and staphylococci?
Testing should incorporate the following CLSI recommendations: Inoculum: Use direct colony suspension Incubation: 35°C, ambient air, for a full 24 hr. Endpoint: Examine very closely for any indication of growth According to the newest CLSI (formerly NCCLS) standards, a vancomycin-intermediate or –resistant result for staphylococci isolate should be verified by repeating a validated MIC method and the organism identification.