TABLE 3.

Isoelectric points and susceptibilities of AmpC-producing isolates of K. pneumoniae

StrainHospital sitePFGE typepIaMIC (μg/ml) ofb:
AMPCAZCAZ/CLACROATMFEPFOXPIPPIP/TZBCIPLVXIMPERT
MCV-4123B19.0, 5.4>4,096646432320.131,024128640.060.130.50.5
MCV-80G123H19.0, 5.4, 7.6>4,09664648320.13512>1,024320.060.060.50.5
MCV-63123C17.2, 5.6, 7.64,09612832840.55121,02432880.50.13
MCV-29155O17.3, 5.8>4,096128648160.52561,0246432320.030.06
MCV-30155P17.3, 5.6>4,0966432841256128640.510.030.03
  • a The first isoelectric point listed for each isolate corresponds to the cloxacillin-inhibited band (AmpC); additional pIs correspond to CLA-inhibited bands.

  • b Abbreviations: AMP, ampicillin; CAZ, ceftazidime; CLA, clavulanic acid (4 μg/ml); CRO, ceftriaxone; ATM, aztreonam; FEP, cefepime; FOX, cefoxitin; PIP, piperacillin; TZB, tazobactam (4 μg/ml); CIP, ciprofloxacin; LVX, levofloxacin; IMP, imipenem; ERT, ertapenem.