TABLE 3.
MICs of β-lactams in the presence of a fixed concentration of 5 μg/ml clavulanate
| Drug | MIC50 (μg/ml)a |
MIC90 (μg/ml)a |
Ratio rangeb (%) |
|||||||
|---|---|---|---|---|---|---|---|---|---|---|
| − | + | − | + | 0.031 | 0.062 | 0.125 | 0.25 | 0.5 | 1 | |
| Amoxicillin | 128 | 64 | 256 | 256 | 3 (2.5) | 4 (3.3) | 17 (14.0) | 23 (19.0) | 42 (34.7) | 32 (26.4) |
| Imipenem | 32 | 32 | 128 | 128 | 0 (0.0) | 0 (0.0) | 0 (0.0) | 6 (5.0) | 23 (19.0) | 92 (76.0) |
| Meropenem | 16 | 4 | 32 | 32 | 5 (4.1) | 5 (4.1) | 4 (3.3) | 27 (22.3) | 53 (43.8) | 27 (22.3) |
| Biapenem | 8 | 8 | 32 | 16 | 2 (1.7) | 2 (1.7) | 3 (2.5) | 11 (9.1) | 52 (43.0) | 51 (42.1) |
a
−, Medium supplemented without clavulanate; +, medium supplemented with clavulanate.
b
Ratio represents the MIC value with clavulanate divided by MIC value without clavulanate.