TABLE 3.
MBECs of vancomycin for S. epidermidis biofilmsa
| No. of duplicate evaluation | Inoculum sizeb | No. of viable cells recovered (no. of CFU/bead) for vancomycin concn (μg/ml) of:
|
|||||
|---|---|---|---|---|---|---|---|
| 10 | 8 | 6 | 4 | 2 | 0 | ||
| Run 1 | 7 × 105 | <1 × 101 (−, 99.9)c | 9 × 101 (−, 99.9) | 4 × 102 (−, 99.9) | 3 × 106 (−, 0) | NA (+) | NA (+) |
| Run 2 | 5.3 × 105 | 1.9 × 101 (−, 99.9) | 2.5 × 101 (−, 99.9) | 7.5 × 103 (−, 98.59) | 1.9 × 106 (−, 0) | NA (+) | NA (+) |
| Run 3 | 1.2 × 106 | <1 × 101 (−, 99.99) | 3.1 × 102 (−, 99.97) | 9.1 × 102 (−, 99.92) | 6.5 × 105 (−, 45.8) | NA (+) | NA (+) |
| Mean percent biofilm eradication | >99.9 | 99.9 | 99.48 | 15.3 | |||
a
S. epidermidis biofilms growing on beads (5.3 × 105 to 1.2 × 106 CFU/bead) were subjected to three independent test evaluations.
b
For each evaluation, a representative inoculum size was established by determining the mean number of CFU per bead for at least two untreated, biofilm-colonized beads that were randomly selected. This value served as a reference for comparison with viable biofilm cell counts for beads exposed to the various vancomycin concentrations. NA, not applicable (therefore, no further assessment was done).
c
Information in parentheses represents the growth turbidity (+, turbid [visible growth in tube]; −, no visible growth, i.e., inhibition of growth), percent eradication.