TABLE 3.

K. pneumoniae MIC values for extended-spectrum cephalosporins and aztreonam

Strainβ-LactamaseInoculum (CFU/ml)MIC (μg/ml) of antimicrobial agent(s)a:
CTXCTX-CACAZCAZ-CAATMATM-CACPDCPD-CAFEPFEP-CA
ATCC 13883None105≤0.12≤0.12≤0.12≤0.12≤0.12≤0.12≤0.12≤0.12≤0.12≤0.12
106≤0.12≤0.120.25≤0.12≤0.12≤0.12≤0.12≤0.12≤0.12≤0.12
ATCC 700603SHV-1810510.580.520.25810.50.5
10640.58140.25820.50.5
OC4244SHV-5, TEM-1105>1280.25>1280.5>128≤0.12>1280.532≤0.12
106>1280.25>1281>128≤0.12>1280.5>128≤0.12
OC4239TEM-6, SHV-11050.25≤0.1264132≤0.12160.52≤0.12
1060.5≤0.12>128264≤0.12640.252≤0.12
OC4110TEM-101051≤0.12128164≤0.12320.252≤0.12
1064≤0.12>1281128≤0.12>1280.52≤0.12
OC4105TEM-26, SHV-11052≤0.12>12841280.25160.258≤0.12
1062≤0.12>12841280.25320.5160.25
OC4074MIR-1, TEM-110581632321616641280.50.5
10681632321632128>12811
OC4076bK-11051≤0.120.25≤0.1216≤0.128≤0.121≤0.12
1062≤0.120.25≤0.121280.25320.2540.25
OC4250ACT-1, TEM, SHV105163264323232646410.5
1063232128643232>128>12820.5
OC5064FOX-5, TEM, SHV105161664644412812810.5
10616326412888>12812811
  • a The antimicrobial agents were each tested alone and with clavulanic acid (CA) at 4 μg/ml. Drug abbreviations: CTX, cefotaxime; CAZ, ceftazidime; ATM, aztreonam; CPD, cefpodoxime; FEP, cefepime.

  • b K. oxytoca.