Table 1.
Overall susceptibility results for the 17 CF MRSA strains that were classified as strongly adherent/strong biofilm producers according to the Biofilm Ring Test® assay.
| Antimicrobial agent | Minimal inhibitory concentration (MIC in mg/L) | Minimal biofilm inhibitory concentration (bMIC in mg/L) | ||||||
|---|---|---|---|---|---|---|---|---|
| Range | MIC50 | MIC90 | Resistant (%, n) | Range | bMIC50 | bMIC90 | Above the threshold for resistance (%, n) | |
| Ceftaroline | <0.125–0.25 | 0.125 | 0.25 | 0 | <0.125–4 | 0.25 | 4 | 23.5 (4) |
| Ceftobiprole | <0.25 | <0.25 | <0.25 | 0 | <0.25–16 | 2 | 8 | 29.4 (5) |
| Linezolid | <0.5–32 | 1 | 16 | 17.6 (3) | <0.5–>64 | 2 | >64 | 35.3 (6) |
| Rifampicin | <0.015–2 | 2 | 2 | 64.7 (11) | <0.015–>2 | >2 | >2 | 82.4 (14) |
| Trimethoprim | <0.25–2 | 0.5 | 2 | 0 | 8–>32 | >32 | >32 | 100 (17) |
European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints for resistance were as follows: ceftaroline, 1mg/L; ceftobiprole, 2mg/L; linezolid, 4mg/L; trimethoprim, 4mg/L, and rifampicin, 0.5mg/L.