TABLE 4.
MIC ranges at 24, 48, and 72 h for CRAB isolates
| Regimenc | MIC in µg/mla,b |
||||||||
|---|---|---|---|---|---|---|---|---|---|
| Minocycline (susceptible MIC = 2) |
Polymyxin B (susceptible MIC = 2) |
Sulbactam (susceptible MIC = 4) |
|||||||
| 24h | 48h | 72h | 24h | 48 h | 72 h | 24h | 48 h | 72 h | |
| Monotherapy | |||||||||
| Minocycline 200 mg load, 100 mg Q12h (SD) | 4–6 | 12–16 | 12–24 | – | – | – | – | – | – |
| Meropenem 1 g Q8h | – | – | – | – | – | – | – | – | – |
| Meropenem 2 g Q8h | – | – | – | – | – | – | – | – | – |
| Polymyxin B 2.5 mg/kg Q12h | – | – | – | 48–96 | 256–512 | 128–256 | – | – | – |
| Sulbactam 1 g Q6h | – | – | – | – | – | – | 64 | 64 | 24–96 |
| Dual therapy | |||||||||
| Minocycline SD + meropenem 2 g Q8h | 12 | 8–12 | 8 | – | – | – | – | – | – |
| Minocycline SD + sulbactam 1 g Q6h | 6 | 8–32 | 8–16 | – | – | – | 8–16 | 12–>256 | 12–>256 |
| Minocycline SD + polymyxin B 2.5 mg/kg Q12h | 4 | 16 | 24–64 | 3-4 | 16 | 16 | – | – | – |
| Meropenem 2 g Q8h + sulbactam 1 g Q6h | – | – | – | – | – | – | 3–16 | 32–96 | 16–32 |
| Minocycline HD + polymyxin B | 2–4 | 8 | 16 | 2 | 2 | 4 | – | – | – |
| Polymyxin B + sulbactam 9 g/24 h CI | – | – | – | 4–6 | 8–16 | 8–16 | 6–12 | >256 | >256 |
| Triple therapy | |||||||||
| Minocycline 700 mg load, 350 mg Q12h (HD) + meropenem 6 g/24 h CI + sulbactam 9 g/24 h CI | 6 | 8 | 8 | – | – | – | 4–6 | 12 | 12 |
| Minocycline HD + polymyxin B + sulbactam 9 g/24 h CI | 6–8 | 6–8 | 4–6 | 8–12 | 4 | 4 | 4 | 3–4 | 3–4 |
a
All MICs determined using E-tests and represent the range determined by duplicate runs. The meropenem MIC is 128 µg/ml.
b
CLSI breakpoints used for susceptibility: minocycline ≤4; polymyxin B ≤2, meropenem ≤2; and ampicillin/sulbactam ≤8/4; –, not applicable.
c
HD, high dose; SD, standard dose; CI, continuous infusion.