TABLE 1.

Results of carbapenem susceptibility testing of 62 KPC-possessing K. pneumoniae isolates according to various testing procedures

Drug and methodMIC (μg/ml)% Susceptible% Intermediate% Resistant
50%a90%bRange
Imipenem
    Clinical laboratory153550
    Broth dilution
        Inoculum = 105 CFU/ml32>32≤0.5->3251679
        Inoculum = 104 CFU/ml832≤0.5->32443719
    Etest>32>324->322296
    Disk diffusion2098
Meropenem
    Clinical laboratory (n = 42)12583
    Broth dilution
        Inoculum = 105 CFU/ml32>321->322098
        Inoculum = 104 CFU/ml832≤0.5->3257718
Etest>32>322->325293
Disk diffusion2296
Ertapenem
    Broth dilution
        Inoculum = 105 CFU/ml32>32≤0.5->322098
        Inoculum = 104 CFU/ml32>32≤0.5->322395
Etest>32>3216->3200100
Disk diffusion00100
  • a MIC for 50% of strains tested.

  • b MIC for 90% of strains tested.