TABLE 1

Susceptibility distribution of 82 imipenem-susceptible but meropenem-resistant Enterobacteriaceae strains carrying blaIMP-6

Antibacterial(s)No. of strains with indicated MIC (mg/liter)MIC50 (mg/liter)MIC90 (mg/liter)
≤0.0310.0630.1250.250.512481632>32
Imipenem 244135 0.51
Meropenem 319332431632
Cefepime 1121 176>32>32
Cefiderocol25174615132 0.0631
Ceftolozane-tazobactama 1472545>32>32
Ceftazidime-avibactama 613283532>32
Aztreonam-avibactama 30b26188 0.1250.25
Ciprofloxacin274 24121537107432
Amikacin 224252281 28
Colistin 11646134 1 10.250.5
  • a Fixed concentration of 4 mg/liter.

  • b MIC, ≤0.063 mg/liter.