TABLE 2.
Antimicrobial activity of linezolid tested against the main organisms and organism groups of isolates included during 2015
| Organisms/no. of isolates | No. of isolates (cumulative %) at MIC (μg/ml) of: |
MIC50 (μg/ml) | MIC90 (μg/ml) | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 0.06 | 0.12 | 0.25 | 0.5 | 1 | 2 | 4 | 8 | >8 | |||
| Staphylococcus aureus (3,031) | 3 (0.1) | 23 (0.9) | 1186 (40.0) | 1773 (98.5) | 45 (>99.9) | 0 (>99.9) | 1 (100.0) | 1 | 1 | ||
| Methicillin susceptible (1,640) | 2 (0.1) | 9 (0.7) | 571 (35.5) | 1023 (97.9) | 35 (100.0) | 1 | 1 | ||||
| Methicillin resistant (1,391) | 1 (0.1) | 14 (1.1) | 615 (45.3) | 750 (99.2) | 10 (99.9) | 0 (99.9) | 1 (100.0) | 1 | 1 | ||
| Coagulase-negative staphylococci (924) | 4 (0.4) | 103 (11.6) | 562 (72.4) | 240 (98.4) | 8 (99.2) | 0 (99.2) | 0 (99.2) | 7 (100.0) | 0.5 | 1 | |
| Methicillin susceptible (381) | 3 (0.8) | 48 (13.4) | 232 (74.3) | 97 (99.7) | 1 (100.0) | 0.5 | 1 | ||||
| Methicillin resistant (543) | 1 (0.2) | 55 (10.3) | 330 (71.1) | 143 (97.4) | 7 (98.7) | 0 (98.7) | 0 (98.7) | 7 (100.0) | 0.5 | 1 | |
| Enterococcus spp. (973) | 26 (2.7) | 267 (30.1) | 605 (92.3) | 72 (99.7) | 1 (99.8) | 2 (100.0) | 1 | 1 | |||
| E. faecalis (676) | 11 (1.6) | 192 (30.0) | 429 (93.5) | 43 (99.9) | 1 (100.0) | 1 | 1 | ||||
| E. faecium (270) | 14 (5.2) | 65 (29.3) | 164 (90.0) | 25 (99.3) | 0 (99.3) | 2 (100.0) | 1 | 1 | |||
| Streptococcus pneumoniae (850) | 3 (0.4) | 193 (23.1) | 620 (96.0) | 34 (100.0) | 1 | 1 | |||||
| Penicillin intermediate (MIC, ≥0.12 and ≤1 μg/ml) (249) | 1 (0.4) | 45 (18.5) | 198 (98.0) | 5 (100.0) | 1 | 1 | |||||
| Penicillin resistant (MIC, ≥2 μg/ml) (64) | 30 (46.9) | 33 (98.4) | 1 (100.0) | 1 | 1 | ||||||
| Viridans group streptococci (236) | 4 (1.7) | 2 (2.5) | 8 (5.9) | 134 (62.7) | 88 (100.0) | 0.5 | 1 | ||||
| Beta-hemolytic streptococci (727) | 180 (24.8) | 547 (100.0) | 1 | 1 | |||||||