TABLE 3.
Fitted PD parameters for four ciprofloxacin dosage regimens against E. coli strains for which the MICs differ
| Parametera | Median (range) for strains for which the MIC (mg/liter) is:
|
||
|---|---|---|---|
| 0.03 (n = 4) | 0.5 (n = 4) | 2.0 (n = 2) | |
| r2 | 0.985 (0.975-0.997) | 0.946 (0.896-0.984) | 0.763 (0.663-0.863) |
| VGmax (CFU/ml/h) | 2.45 × 106 (2.00 × 106-2.87 × 106) | 4.56 × 107 (3.39 × 107-5.71 × 107) | 3.09 × 107 (2.75 × 107-3.43 × 107) |
| CFUm (CFU/ml) | 3.40 × 105 (2.79 × 105-4.34 × 105) | 3.55 × 107 (2.78 × 107-4.36 × 107) | 5.66 × 107 (4.27 × 107-7.04 × 107) |
| Kd (h−1) | 0.297 (0.279-0.320) | 0.274 (0.222-0.308) | 0.199 (0.106-0.293) |
| SITms | 0.040 (0.034-0.040) | 0.099 (0.096-0.106) | 1.89 (1.88-1.91) |
| SITmi | 1.79 (1.17-2.26) | ||
| H | 2.47 (2.44-2.47) | 2.31 (1.00-3.21) | 1.80 (1.46-2.13) |
| Emax | 28.7 (23.9-36.8) | 27.7 (8.39-49.7) | 43.2 (39.5-46.8) |
| IC4 (CFU/ml) | 1.02 × 108 (7.36 × 107-1.27 × 108) | 5.88 × 107 (9.08 × 106-1.39 × 108) | 5.57 × 107 (5.04 × 107-6.09 × 107) |
| IC5 (CFU/ml) | 3.86 × 106 (9.51 × 105-5.11 × 107) | ||
a
SITms, median effect serum inhibitory titer for a relatively sensitive subpopulation; SITmi, median effect serum inhibitory titer for a relatively intermediately sensitive subpopulation; H, Hill’s constant; Emax, maximum fractional increase in Kd; IC4, initial condition of the sensitive-subpopulation compartment; IC5, initial condition of the intermediate-subpopulation compartment.