Table 1.
Characteristics of the challenge set of 92 P. aeruginosa isolates utilized in algorithm development.
| Susceptibility | Carbapenemase Producers, n = 57 |
Non-Carbapenemase Producers, | Test Performance | ||
|---|---|---|---|---|---|
| Cephalosporinase or Efflux/Porin Mutation, n = 20 | Wild Type, n = 15 | Sensitivity, % (95% CI) | Specificity, % (95% CI) | ||
| IPM + MEM- Resistant | 57 (100%) | 15 (75%) | 1 (7%) | 100% (94–100%) | 54% (37–71%) |
| IPM + MEM- Resistant AND FEP + CAZ + TZP- Non-Susceptible |
57 (100%) | 12 (60%) | 0 (0%) | 100% (94–100%) | 66% (48–81%) |
| IPM + MEM- Resistant AND FEP + CAZ + TZP- Resistant |
47 (82%) | 6 (30%) | 0 (0%) | 83% (70–91%) | 83% (66–93%) |
| IPM + MEM- Resistant AND FEP + CAZ + TZP- Non-Susceptible + CZA- Resistant |
49 (86%) | 8 (40%) | 0 (0%) | 86% (74–94%) | 77% (60–90%) |
| IPM + MEM- Resistant AND FEP + CAZ + TZP- Non-Susceptible + C/T- Resistant |
57 (100%) | 4 (20%) | 0 (0%) | 100% (94–100%) | 89% (73–97%) |
| IPM + MEM- Resistant AND FEP + CAZ + TZP- Non-Susceptible + C/T- Resistant + CZA- Resistant |
49 (86%) | 3 (15%) | 0 (0%) | 86% (74–94%) | 91% (77–98%) |
IPM = imipenem; MEM = meropenem; FEP = cefepime; CAZ = ceftazidime; TZP = piperacillin/tazobactam; CZA = ceftazidime/avibactam; C/T = ceftolozane/tazobactam; Sensitivity and Specificity = calculated based on prediction the criteria accurately identify carbapenemase production; 95%CI = 95% confidence interval.