TABLE 3.
Activity of antibiotics or control against 22 VREF isolates causing catheter-related bacteremia in suspension (MIC) and in biofilm
| Antibiotic or control | MIC range (mg/liter) | Biofilm (mean CFU per disk ± SEM)a |
|---|---|---|
| Daptomycin | 2.0-8.0 | 1.3 × 102 ± 2.7 × 101 |
| Minocycline | ≥0.06-8.0 | 5.6 × 102 ± 1.2 × 102 |
| Quinupristin-dalfopristin | ≥0.06-2.0 | 3.0 × 103 ± 1.8 × 102 |
| Linezolid | 0.5-2.0 | 4.3 × 103 ± 1.4 × 102 |
| Control (water) | 5.0 × 103 ± 0 |
a
Colonization data are after 24 h of exposure to 2,000 mg/liter of antibiotic. All antibiotics significantly reduced biofilm colonization compared with control (P, ≤0.01). Daptomycin was more effective than minocycline (P, <0.001). Minocycline was significantly more effective than quinupristin-dalfopristin (P, <0.01), and quinupristin-dalfopristin was significantly more effective than linezolid (P, <0.01). A total of 660 disks were tested using 6 disks per isolate and a particular antibiotic or water.