TABLE 1

Antimicrobial susceptibility profiles of the original KPC-producing K. pneumoniae isolates and transformantsa

MIC (µg/ml) (category) forc
Antibiotic(s)K. pneumoniae 45K. pneumoniae SG1bK. pneumoniae 44bE. coli DH5α 45-1TE. coli DH5α 48-1T
(ST512 IncX3, two blaKPC genes)(ST512 pKpQIL, one blaKPC gene)(ST258 pKpQIL, one blaKPC gene)(IncX3, two blaKPC genes)(pKpQIL, one blaKPC gene)
Piperacillin-tazobactam≥128 (R)≥128 (R)≥128 (R)≥128 (R)32 (S)
Ticarcillin-clavulanate≥256 (R)≥256 (R)≥256 (R)≥256 (R)≥256 (R)
Cefoxitin≥128 (NA)≥128 (NA)≥128 (NA)16 (NA)16 (NA)
Cefpodoxime≥64 (R)≥64 (R)≥64 (R)≥64 (R)≥64 (R)
Ceftriaxone≥256 (R)≥256 (R)≥256 (R)32 (R)4 (R)
Cefotaxime≥128 (R)≥128 (R)≥128 (R)8 (R)4 (R)
Cefotaxime-clavulanate≥128 (NA)≥128 (NA)≥128 (NA)4 (NA)0.25 (NA)
Ceftazidime≥256 (R)≥256 (R)≥256 (R)64 (R)16 (R)
Ceftazidime-clavulanate≥256 (NA)≥256 (NA)≥256 (NA)32 (NA)4 (NA)
Cefepime≥32 (R)≥32 (R)≥32 (R)8 (R)2 (S)
Aztreonam≥32 (R)≥32 (R)≥32 (R)≥32 (R)≥32 (R)
Imipenem≥32 (R)≥32 (R)≥32 (R)2 (S)≥0.25 (S)
Meropenem≥16 (R)≥16 (R)≥16 (R)1 (S)≤0.5 (S)
Ertapenem≥8 (R)≥8 (R)≥8 (R)1 (I)≤0.125 (S)
Doripenem≥4 (R)≥4 (R)≥4 (R)0.5 (S)0.25 (S)
Gentamicin1 (S)≤0.5 (S)2 (S)≤0.5 (S)≤0.5 (S)
Tobramycin≥16 (R)≥16 (R)≥16 (R)≤0.5 (S)≤0.5 (S)
Amikacin16 (I)16 (I)32 (R)≤2 (S)≤2 (S)
Ciprofloxacin≥4 (R)≥4 (R)≥4 (R)≤0.125 (S)≤0.125 (S)
Levofloxacin≥16 (R)≥16 (R)≥16 (R)≤0.5 (S)≤0.5 (S)
Trimethoprim-sulfamethoxazole2 (S)2 (S)2 (S)≤0.25 (S)≤0.25 (S)
Colistin4 (R)≤0.25 (S)≥8 (R)≤0.125 (S)≤0.125 (S)
Polymyxin B1 (NA)0.5 (NA)≥8 (R)≤0.125 (S)≤0.125 (S)
Doxycycline8 (NA)8 (NA)4 (NA)≤1 (NA)≤1 (NA)
Minocycline16 (NA)8 (NA)4 (NA)≤1 (NA)≤1 (NA)
Tigecycline0.5 (S)0.5 (S)0.5 (S)≤0.125 (S)≤0.125 (S)
  • a R, resistant; I, intermediate; S, susceptible; NA, not applicable.

  • b K. pneumoniae strains ST512 and ST258-44 were previously described in Capone et al. (18) and Bonura et al. (4).

  • c According to the EUCAST 2015 criteria. MICs were obtained by implementing ESB1F and GNX2F plates (Trek Diagnostics).