TABLE 2.
Activity of ceftazidime-avibactam and comparator antimicrobial agents when tested against P. aeruginosa from U.S. hospitals (2012 to 2013)
| Antimicrobial agenta | MIC (μg/ml) |
%S/%I/%R according to indicated criteriab |
|||
|---|---|---|---|---|---|
| 50% | 90% | Range | CLSI | EUCAST | |
| All isolates (n = 3,902) | |||||
| Ceftazidime-avibactam | 2 | 4 | 0.03 to >32 | 96.9/0.0/3.1c | 96.9/0.0/3.1d |
| Ceftazidime | 2 | 32 | 0.06 to >32 | 83.8/3.6/12.6 | 83.8/0.0/16.2 |
| Cefepime | 2 | 16 | ≤0.5 to >16 | 83.6/8.4/8.0 | 83.6/0.0/16.4 |
| Piperacillin-tazobactam | 8 | >64 | ≤0.5 to >64 | 78.5/9.1/12.4 | 78.5/0.0/21.5 |
| Meropenem | 0.5 | 8 | ≤0.06 to >8 | 81.9/5.8/12.3 | 81.9/11.9/6.2 |
| Ciprofloxacin | 0.12 | >4 | ≤0.03 to >4 | 77.0/5.1/17.9 | 71.8/5.2/23.0 |
| Levofloxacin | 0.5 | >4 | ≤0.12 to >4 | 74.9/6.4/18.7 | 66.5/8.4/25.1 |
| Gentamicin | ≤1 | 8 | ≤1 to >8 | 88.9/3.2/7.9 | 88.9/0.0/11.1 |
| Amikacin | 2 | 8 | ≤0.25 to >32 | 97.4/1.1/1.5 | 94.0/3.4/2.6 |
| Colistin | 1 | 2 | 0.12 to >8 | 99.3/0.6/0.1 | 99.9/0.0/0.1 |
| MDR strains (n = 580) | |||||
| Ceftazidime-avibactam | 4 | 16 | 0.25 to >32 | 81.0/0.0/19.0c | 81.0/0.0/19.0d |
| Ceftazidime | 32 | >32 | 1 to >32 | 22.4/16.0/61.6 | 22.4/0.0/77.6 |
| Cefepime | 16 | >16 | 1 to >16 | 22.9/34.9/42.2 | 22.9/0.0/77.1 |
| Piperacillin-tazobactam | >64 | >64 | 1 to >64 | 8.6/30.5/60.9 | 8.6/0.0/91.4 |
| Meropenem | 8 | >8 | ≤0.06 to >8 | 21.6/16.3/62.1 | 21.6/43.9/34.5 |
| Ciprofloxacin | >4 | >4 | ≤0.03 to >4 | 20.9/10.1/69.0 | 13.6/7.3/79.1 |
| Levofloxacin | >4 | >4 | ≤0.12 to >4 | 15.0/13.3/71.7 | 9.8/5.2/85.0 |
| Gentamicin | 4 | >8 | ≤1 to >8 | 51.4/9.5/39.1 | 51.4/0.0/48.6 |
| Amikacin | 4 | 32 | ≤0.25 to >32 | 87.9/5.0/7.1 | 76.6/11.3/12.1 |
| Colistin | 1 | 2 | 0.25 to >8 | 99.0/0.7/0.3 | 99.7/0.0/0.3 |
| XDR strains (n = 338) | |||||
| Ceftazidime-avibactam | 8 | 32 | 0.5 to >32 | 73.7/0.0/26.3c | 73.7/0.0/26.3d |
| Ceftazidime | 32 | >32 | 1 to >32 | 10.1/17.1/72.8 | 10.1/0.0/89.9 |
| Cefepime | >16 | >16 | 4 to >16 | 11.8/32.3/55.9 | 11.8/0.0/88.2 |
| Piperacillin-tazobactam | >64 | >64 | 8 to >64 | 2.7/23.6/73.7 | 2.7/0.0/97.3 |
| Meropenem | 8 | >8 | 0.12 to >8 | 7.1/14.8/78.1 | 7.1/47.3/45.6 |
| Ciprofloxacin | >4 | >4 | 0.12 to >4 | 7.7/9.5/82.8 | 2.7/5.0/92.3 |
| Levofloxacin | >4 | >4 | 0.25 to >4 | 3.6/11.2/85.2 | 2.1/1.4/96.5 |
| Gentamicin | >8 | >8 | ≤1 to >8 | 37.0/10.0/53.0 | 37.0/0.0/63.0 |
| Amikacin | 8 | 32 | ≤0.25 to >32 | 83.7/6.5/9.8 | 69.8/13.9/16.3 |
| Colistin | 1 | 2 | 0.25 to >8 | 98.8/0.9/0.3 | 99.7/0.0/0.3 |
a
MDR, multidrug resistant; XDR, extensively drug resistant (17).
b
S, susceptible; I, intermediate; R, resistant, according to criteria as published by the CLSI (15) and EUCAST (16).
c
U.S. FDA breakpoint criteria were applied (11).
d
EUCAST susceptibility criteria for ceftazidime alone were applied for comparison purposes only (16).