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. 2014 Nov;58(11):6490–6495. doi: 10.1128/AAC.03579-14

TABLE 1.

MICs against isolates of Enterobacteriaceae reported in Table 3

Isolate Phenotype β-Lactamase MIC (μg/ml) for:
Ceftazidime
 Amoxicillin-clavulanated Piperacillin-tazobactame
Alone + Avibactam
4 μg/mla 4:1b 8:1c
E. coli 250GR12 CAZ-S 0.06 0.06 0.06 0.06 2 2
E. coli 250GR43 CAZ-S 0.25 0.12 0.12 0.12 4 1
K. pneumoniae 283GR4 CAZ-S 0.25 0.5 0.25 0.25 16 32
K. pneumoniae 283IP53 CAZ-S ≤0.12 ≤0.12 0.12 0.12 4 4
P. stuartti 321UC1 CAZ-S 1 0.5 0.5 1 64 4
E. coli 250BE1 CAZ-R SHV-4 ≥128 0.25 2 4 8 16
K. pneumoniae 283IP10 CAZ-R AmpC; SHV-4 64 0.5 1 2 8 >32
K. pneumoniae 283IP35 CAZ-R SHV-2 ≥128 0.25 0.5 1 64 32
K. pneumoniae 283IP84 CAZ-R TEM-3 64 0.25 2 8 32 32
E. cloacae 293GR8 CAZ-R AmpC ≥128 0.5 1 2 ≥128 32
E. cloacae 293GR38 CAZ-R AmpC 64 0.5 1 1 64 >32
E. cloacae P99 CAZ-R AmpC ≥128 0.5 0.5 1 ≥128 >32
C. freundii 261GR3 CAZ-R AmpC ≥128 0.06 1 1 ≥128 32
C. freundii 261GR6 CAZ-R AmpC ≥128 0.5 2 2 ≥128 32
a

MICs for ceftazidime in the presence of a fixed 4-μg/ml avibactam concentration.

b

MICs for ceftazidime when combined with avibactam in a 4:1 (wt/wt) ratio.

c

MICs for ceftazidime when combined with avibactam in a 8:1 (wt/wt) ratio.

d

Commercially available amoxicillin-clavulanate (1/0.2 g) (Augmentin).

e

Commercially available piperacillin-tazobactam (4/0.5 g) (Tazocillin).