TABLE 2

Breakpoints used for prediction of S. schleiferi mecA-mediated oxacillin resistance in this studya

OrganismOxacillin breakpointCefoxitin breakpoint
DD inhibition zone (mm)MIC (μg/ml)DD inhibition zone (mm)MIC (μg/ml)
SRSRSRSR
S. aureus/S. lugdunensisNANA≤2≥4≥22≤21≤4≥8
Coagulase-negative staphylococci, except S. lugdunensis and S. pseudintermediusNANA≤0.25≥0.5≥25≤24NANA
S. pseudintermediusb≥18≤17≤0.25≥0.5NANANANA
  • a From the CLSI M100-S27 document (32). NA, not applicable; S, susceptible; R, resistant.

  • b In the 28th edition of the CLSI M100 document, the guidance for S. pseudintermedius will also apply to S. schleiferi.