Table 2.

MIC distributions, antimicrobial susceptibilities, and spectra of activity of the different antimicrobial agents tested for the MRSA isolates testeda

Antimicrobial agentNo. of isolates for which MIC (mg/liter) is:MIC50/MIC90b% Susceptible
<0.030.06≤0.120.120.25≤0.50.512>2≤44>48>8
Erythromycin72840131778644>8/>84.8
Clindamycin1036054127572>8/>823.3
Gentamicin21587565916574>16/>1622.8
Tetracycline30911444>8/>842.9
Doxycycline3005221502874/885.2
Minocycline1321610374272/492.3
Ciprofloxacin1916239129605>2/>29.2
Gatifloxacinc 182319511793762332/4
Trovafloxacinc 431479972551951441/>4
Rifampin33240920783342/>246.1
Chloramphenicol1122101804381308/1683.0
Quinupristin-dalfopristin241674271111431260.5/199.5
Linezolidc,d 06716622013002/2
Teicoplanin53515826023663521/299.7
Vancomycin11654932004001/2100
  • a A total of 764 MRSA isolates were tested.

  • b MIC50/MIC90, MICs at which 50%/90% of isolates are inhibited.

  • c Investigational drug. No susceptibility breakpoints are available (10).

  • d Only 412 MRSA isolates were tested, unless indicated otherwise.