TABLE 4.
Cross-resistance of P. aeruginosa isolates to β-lactams and ceftolozane-tazobactama
| Isolate and β-lactam | % NS isolates | Of NS isolates, % S to: |
||||
|---|---|---|---|---|---|---|
| FEP | CAZ | TZP | MEM | C-T | ||
| All patient isolates | ||||||
| Cefepime | 23.0 | NA | 23.9 | 20.8 | 39.4 | 87.5 |
| Ceftazidime | 23.0 | 23.9 | NA | 15.2 | 41.2 | 86.2 |
| Piperacillin-tazobactam | 28.2 | 35.3 | 30.8 | NA | 45.2 | 90.1 |
| Meropenem | 24.0 | 42.1 | 43.7 | 35.8 | NA | 90.1 |
| ICU patient isolates | ||||||
| Cefepime | 28.4 | NA | 16.7 | 13.7 | 37.3 | 84.3 |
| Ceftazidime | 31.2 | 24.1 | NA | 11.6 | 37.5 | 83.9 |
| Piperacillin-tazobactam | 37.0 | 33.8 | 25.6 | NA | 41.4 | 88.0 |
| Meropenem | 30.1 | 40.7 | 35.2 | 27.8 | NA | 87.0 |
| Non-ICU patient isolates | ||||||
| Cefepime | 20.8 | NA | 27.8 | 24.6 | 40.6 | 89.3 |
| Ceftazidime | 19.7 | 23.7 | NA | 17.5 | 43.5 | 87.6 |
| Piperacillin-tazobactam | 24.6 | 36.2 | 33.9 | NA | 47.5 | 91.4 |
| Meropenem | 21.6 | 42.8 | 48.5 | 40.2 | NA | 91.8 |
| Respiratory isolates | ||||||
| Cefepime | 30.4 | NA | 18.1 | 16.1 | 41.6 | 83.2 |
| Ceftazidime | 30.0 | 17.0 | NA | 10.9 | 40.8 | 83.0 |
| Piperacillin-tazobactam | 36.9 | 30.9 | 27.6 | NA | 45.9 | 87.3 |
| Meropenem | 29.6 | 40.0 | 40.0 | 32.4 | NA | 85.5 |
| Nonrespiratory isolates | ||||||
| Cefepime | 18.3 | NA | 30.0 | 25.7 | 37.1 | 92.1 |
| Ceftazidime | 18.5 | 31.0 | NA | 19.7 | 41.5 | 89.4 |
| Piperacillin-tazobactam | 22.6 | 39.9 | 34.1 | NA | 44.5 | 93.1 |
| Meropenem | 20.5 | 43.9 | 47.1 | 38.9 | NA | 94.3 |
| ICU patient respiratory isolates | ||||||
| Cefepime | 40.4 | NA | 17.5 | 11.1 | 31.7 | 81.0 |
| Ceftazidime | 39.7 | 16.1 | NA | 8.1 | 32.3 | 80.6 |
| Piperacillin-tazobactam | 49.4 | 27.3 | 26.0 | NA | 32.5 | 83.6 |
| Meropenem | 41.0 | 32.8 | 34.4 | 18.8 | NA | 85.7 |
| ICU patient nonrespiratory isolates | ||||||
| Cefepime | 19.2 | NA | 15.4 | 17.9 | 46.2 | 89.7 |
| Ceftazidime | 24.6 | 34.0 | NA | 16.0 | 44.0 | 88.0 |
| Piperacillin-tazobactam | 27.6 | 42.9 | 25.0 | NA | 53.6 | 91.1 |
| Meropenem | 21.7 | 52.3 | 36.4 | 40.9 | NA | 93.2 |
| Non-ICU patient respiratory isolates | ||||||
| Cefepime | 25.7 | NA | 18.6 | 19.8 | 48.8 | 84.9 |
| Ceftazidime | 25.4 | 17.6 | NA | 12.9 | 47.1 | 84.7 |
| Piperacillin-tazobactam | 31.1 | 33.7 | 28.8 | NA | 55.8 | 88.5 |
| Meropenem | 24.3 | 45.7 | 44.4 | 43.2 | NA | 87.7 |
| Non-ICU patient nonrespiratory isolates | ||||||
| Cefepime | 17.9 | NA | 35.6 | 28.7 | 33.7 | 93.1 |
| Ceftazidime | 16.3 | 29.3 | NA | 21.7 | 40.2 | 90.2 |
| Piperacillin-tazobactam | 20.7 | 38.5 | 38.5 | NA | 40.2 | 94.0 |
| Meropenem | 20.0 | 40.7 | 51.3 | 38.1 | NA | 94.7 |
a
Definitions: CAZ, ceftazidime; C-T, ceftolozane-tazobactam; FEP, cefepime; MEM, meropenem; NA, not applicable; NS, nonsusceptible; TZP, piperacillin-tazobactam; S, susceptible.