TABLE 2.
Sensitivity and specificity results for the LC-MS/MS carbapenem hydrolysis assay
| Carbapenem | Threshold | Group of isolatesa | % Sensitivity (95% CIb) | % Specificity (95% CI) |
|---|---|---|---|---|
| Ertapenem | >0.0750 | All | 67.5 (55.9–77.7) | 97.2 (94.8–98.7) |
| Ent | 74.1 (61.0–84.8) | 96.6 (93.2–98.6) | ||
| NF | 36.8 (16.3–61.6) | 98.4 (94.2–99.8) | ||
| Meropenem | >0.0450 | All | 81.1 (70.3–89.3) | 95.7 (92.9–97.7) |
| Ent | 84.2 (72.1–92.5) | 98.5 (95.8–99.7) | ||
| NF | 68.4 (43.5–87.4) | 91.8 (85.4–96.0) | ||
| Imipenem | >0.3150 | All | 96.0 (88.6–99.2) | 95.1 (92.2–97.2) |
| Ent | 98.3 (90.6–100.0) | 95.6 (91.8–98.0) | ||
| NF | 89.5 (66.9–98.7) | 95.9 (90.7–98.7) |
a
Ent, Enterobacteriaceae; NF, non-glucose-fermenting Gram-negative rods.
b
CI, confidence interval.