Table 6.
Bacterial count changes of the three strains after 24 hours (time-kill experiments) and 12 hours (PAE and PA-SME experiments) of exposure to linezolid alone or combination fosfomycin compared to the viable bacterial counts with control
| Drugs | Bacterial counts (CFU/mL)
|
||
|---|---|---|---|
| No. 36 | No. 8 | ATCC 25923 | |
|
| |||
| Time-kill experiments | |||
| Control | 17.53±0.60 | 16.63±0.08 | 16.17±0.09 |
| LIN 1x MIC | 7.88±0.11 | 8.83±0.05 | 8.04±0.04 |
| FOS 1x MIC | 8.11±0.09 | 7.87±0.08 | 7.22±0.04 |
| LIN 1/2x+FOS1/2x MIC | 3.37±0.28 | 3.65±0.05 | 4.12±0.07 |
| LIN 1/2x+FOS 1x MIC | 3.45±0.03 | 3.69±0.01 | 3.67±0.28 |
| LIN 1x+FOS 1/2x MIC | 5.03±0.06 | 4.52±0.17 | 3.55±0.05 |
| LIN 1x+FOS 1x MIC | 2.51±0.43 | 2.73±0.03 | 3.01±0.06 |
| LIN 2x+FOS 2x MIC | 1.88±0.15 | 1.55±0.04 | 2.99±0.09 |
| LIN 4x+FOS 4x MIC | 0.00±0.00 | 0.00±0.00 | 0.00±0.00 |
| PAE experiments | |||
| Control | 13.39±0.04 | 13.65±0.02 | 14.12±0.03 |
| LIN 1x MIC | 10.72±0.04 | 9.85±0.02 | 8.33±0.05 |
| LIN 4x MIC | 7.43±0.06 | 9.71±0.04 | 6.27±0.12 |
| FOS 1x MIC | 9.66±0.02 | 10.51±0.04 | 8.94±0.15 |
| FOS 4x MIC | 8.29±0.05 | 8.49±0.02 | 7.07±0.15 |
| LIN 1x+FOS 1x MIC | 8.72±0.02 | 8.83±0.06 | 8.82±0.27 |
| LIN 4x+FOS 4x MIC | 7.37±0.13 | 6.79±0.04 | 5.31±0.05 |
| PA-SME experiments | |||
| Control (LIN 0.1x MIC) | 13.56±0.05 | 13.88±0.03 | 13.35±0.04 |
| Control (LIN 0.2x MIC) | 12.29±0.03 | 13.71±0.11 | 12.38±0.14 |
| Control (LIN 0.4 x MIC) | 8.05±0.08 | 11.26±0.15 | 9.26±0.14 |
| LIN 0.1x MIC | 6.43±0.07 | 7.27±0.09 | 7.17±0.15 |
| LIN 0.2x MIC | 5.25±0.07 | 6.29±0.01 | 5.26±0.16 |
| LIN 0.4x MIC | 4.30±0.00 | 4.82±0.17 | 4.22±0.17 |
| Control (FOS 0.1x MIC) | 12.54±0.04 | 13.65±0.05 | 14.00±0.03 |
| Control (FOS 0.2x MIC) | 11.31±0.10 | 13.43±0.04 | 13.50±0.10 |
| Control (FOS 0.4x MIC) | 10.99±0.22 | 12.85±0.19 | 11.43±0.11 |
| FOS 0.1x MIC | 7.33±0.08 | 8.27±0.10 | 7.26±0.01 |
| FOS 0.2x MIC | 5.61±0.05 | 7.23±0.11 | 6.69±0.05 |
| FOS 0.4x MIC | 5.32±0.09 | 6.19±0.10 | 5.49±0.15 |
| Control (LIN 0.1x+FOS 0.1x MIC) | 13.74±0.05 | 13.43±0.04 | 13.88±0.15 |
| Control (LIN 0.2x+FOS 0.2x MIC) | 11.24±0.11 | 11.09±0.11 | 12.37±0.30 |
| Control (LIN 0.4x MIC+ FOS 0.4x MIC) | 9.73±0.07 | 9.12±0.17 | 10.36±0.16 |
| LIN 0.1x+FOS 0.1x MIC | 6.77±0.04 | 6.01±0.11 | 7.54±0.12 |
| LIN 0.2x+FOS 0.2x MIC | 5.68±0.03 | 4.33±0.07 | 4.72±0.05 |
| LIN 0.4x+FOS 0.4x MIC | 4.52±0.15 | 3.78±0.07 | 3.18±0.16 |
Note: All data are presented as mean ± SD.
Abbreviations: CFU, colony-forming units; FOS, fosfomycin; LIN, linezolid; MIC, minimum inhibitory concentration; PAE, post-antibiotic effect; PA-SME, post-antibiotic sub-MIC effect.