TABLE 3.

MICs of β-lactams

β-Lactam(s)aMIC (μg/ml)
K. pneumoniae YCE. coli pNYCE. coli pRYCK. pneumoniae GRE. coli pNGRK. pneumoniae 633E. coli pBC633K. pneumoniae 2303E. coli pBC2303P. aeruginosa 2404P. aeruginosa KG2505 pColE. coli pCOLE. coli DH10BP. aeruginosa KG2505
Amoxicillin>256>256>256>256>256>256>256>256>256>256>256>25620.25
Amoxicillin + CLA32326448243232>25624>256>2562420.25
Ticarcillin>256>256>256>256>256>256>256>256>256>256>256>25620.38
Ticarcillin + CLA>256>256>256>256>256>256>256>256>256>256>256>2561.50.25
Piperacillin>256>256>256>256128>256>256>256>256>256>256>2561.50.38
Piperacillin + TZB>25664>256>256128>256>256>256128>2560.38321.50.12
Cephalothin>256>256>256>256>256>256>256>256>256>256>25625622
Cefoxitin>322>32>324>32>32>328>64>32220.25
Cefotaxime>324>32>324>3232>3216>32>3230.050.25
Cefotaxime + CLA162>32320.38>323>320.38>32>320.250.010.19
Ceftazidime644>256>2564>25632>256256>256>25680.191.0
Aztreonam25616>256>25616>256256>256192>256>256240.030.19
Aztreonam + CLA2568>256>2561.5960.32>2562>256>2561.50.020.19
Cefepime16132>321.5>324>323>32>321.00.020.50
Imipenem4812121.5>326>321.0>32>321.50.190.19
Imipenem + CLA2230.750.250.750.75>320.25>3220.380.10.19
Meropenem22360.3842>320.38>32>320.380.010.05
Meropenem + CLA10.25230.0120.38>320.12>3230.10.0020.01
Ertapenem240.504120.38>322>320.25>32>320.250.0040.25
Ertapenem + CLA20.051.560.0180.19>320.02>3220.050.0020.03
  • a CLA, clavulanic acid at a fixed concentration of 2 μg/ml; TZB, tazobactam at a fixed concentration of 4 μg/ml.