Table 1.
In vitro activities of antimicrobial agents against ESBL-producing K. pneumoniae isolates in the GEIH-BLEE-2006 study (n = 162)a
| Agent | MIC (mg/liter) |
% susceptible isolates |
|||
|---|---|---|---|---|---|
| Range | 50% | 90% | 2006 study | 2000 studyb | |
| Cefotaxime | ≤0.5–>128 | >128 | >128 | 0.6 | — |
| Ceftazidime | ≤0.5–>128 | >128 | 64 | 7.4 | — |
| Cefepime | ≤1–>32 | >32 | >32 | 8.0 | — |
| Aztreonam | ≤0.5–>64 | >64 | >64 | 6.8 | — |
| Cefoxitin | ≤2–>32 | 4 | 16 | 87.1 | 94 |
| Cefotetan | ≤1–4 | ≤1 | ≤1 | 100 | 98.5 |
| Imipenem | ≤0.5–1 | ≤0.5 | ≤0.5 | 100 | 100 |
| Meropenem | ≤0.5–2 | ≤0.5 | ≤0.5 | 100 | 100 |
| Ertapenem | ≤0.008–16 | 0.125 | 0.5 | 98.2 | Not tested |
| Amoxicillin-clavulanatec | 8–>128 | 64 | >128 | 4.3 | 40 |
| Piperacillin-tazobactamd | 1–>1,024 | 16 | >1,024 | 55.6 | 74 |
| Nalidixic acid | 2–>1,024 | >1,024 | >1,024 | 28.0 | Not tested |
| Ciprofloxacin | ≤0.008–>128 | 32 | >128 | 37.8 | 88.5 |
| Gentamicin | ≤0.125–>128 | 8 | 128 | 49.4 | 33.0 |
| Tobramycin | ≤0.125–>128 | 16 | 64 | 35.9 | 38.5 |
| Amikacin | 0.25–64 | 1 | 8 | 98.1 | 91.0 |
| Tigecycline | ≤0.008–8 | 0.5 | 4 | Not applicable | Not tested |
| Co-trimoxazolee | ≤0.062–>32 | >32 | >32 | 27.2 | 40.0 |
a
Susceptibility defined by 2010 CLSI breakpoints (4). Data on percentages of susceptibility from isolates obtained in the study performed in 2000 (n = 70) are also presented for comparison.
b
—, not determined (all organisms considered resistant because of ESBL production).
c
The concentrations of amoxicillin are indicated.
d
The concentrations of piperacillin are indicated.
e
The concentrations of trimethoprim are indicated.