TABLE 2.
Linezolid MIC distribution when tested against species and groups of Gram-positive cocci isolated in the United States and submitted to the LEADER Surveillance Program, 2012
| Organisma (no. of isolates [n = 7,429]) | No. (cumulative %) of isolates inhibited at linezolid MIC (μg/ml) of: |
MIC (μg/ml) |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| ≤0.12 | 0.25 | 0.5 | 1 | 2 | 4 | 8 | >8 | MIC50 | MIC90 | |
| S. aureus (2,980) | 1 (0.0) | 5 (0.2) | 290 (9.9) | 2,354 (88.9) | 327 (99.9) | 2 (>99.9) | 0 (>99.9) | 1 (100.0) | 1 | 2 |
| Oxacillin susceptible (1,537) | 0 (0.0) | 3 (0.2) | 140 (9.3) | 1,207 (87.8) | 186 (99.9) | 0 (99.9) | 0 (99.9) | 1 (100.0) | 1 | 2 |
| Oxacillin resistant (1,443) | 1 (0.1) | 2 (0.2) | 150 (10.6) | 1,147 (90.1) | 141 (99.9) | 2 (100.0) | 1 | 1 | ||
| CoNS (753) | 2 (0.3) | 106 (14.3) | 449 (74.0) | 184 (98.4) | 5 (99.1) | 0 (99.1) | 0 (99.1) | 7 (100.0) | 0.5 | 1 |
| Enterococcus spp. (937) | 0 (0.0) | 9 (1.0) | 112 (12.9) | 695 (87.1) | 116 (99.5) | 1 (99.6) | 3 (99.9) | 1 (100.0) | 1 | 2 |
| E. faecalis (640) | 0 (0.0) | 8 (1.3) | 71 (12.3) | 482 (87.7) | 78 (99.8) | 1 (100.0) | 1 | 2 | ||
| E. faecium (259) | 0 (0.0) | 1 (0.4) | 32 (12.8) | 185 (84.5) | 37 (98.8) | 0 (98.8) | 3 (99.6) | 1 (100.0) | 1 | 2 |
| S. pneumoniae (1,273) | 6 (0.5) | 36 (3.3) | 408 (35.3) | 800 (98.2) | 23 (100.0) | 1 | 1 | |||
| VGS (526) | 12 (2.3) | 26 (7.2) | 217 (48.5) | 260 (97.9) | 11 (100.0) | 1 | 1 | |||
| BHS (960) | 1 (0.1) | 2 (0.3) | 258 (27.2) | 699 (100.0) | 1 | 1 | ||||
a
CoNS, coagulase-negative staphylococci; VGS, viridans group streptococci; BHS, beta-hemolytic streptococci.