Table 5.
Antimicrobial susceptibility of Listeria monocytogenes strains to AMP and corresponding combinational therapy with CRO and DAP assessed by MIC and checkerboard assays.a
| MIC (µg/mL) | Checkerboard FICI (Interpretation) | ||||||
|---|---|---|---|---|---|---|---|
|
|
|
||||||
| Strain | AMP | CRO | DAP | AMP/CRO | AMP/DAP | FICIAMP-CRO | FICIAMP-DAP |
| L. monocytogenes | |||||||
| LM SDVA | 1 | 16 | 32 | 0.25/4 | 0.25/1 | 0.5(S) | 0.28125(S) |
| LM L028 | 1 | 8 | 8 | 0.5/2 | 0.5/2 | 0.75(A) | 0.75(A) |
| LM 2203 | 1 | 8 | 16 | 0.25/4 | 0.25/8 | 0.75(A) | 0.75(A) |
| LM 10403S | 0.5 | 8 | 32 | 0.5/1 | 0.25/16 | 1.25(I) | 1(A) |
| LM EDGE | 1 | 8 | 16 | 0.25/2 | 0.5/4 | 0.5(S) | 0.75(A) |
a
AMP, Ampicillin; CRO, Ceftriaxone; DAP, Daptomycin; FICI, Fractional Inhibitory Concentration Index; MIC, minimum inhibitory concentration; S, Synergy; A, Additivity; I, Indifference.