Table 8.
FICI calculated for five different antibiotic combinations for MDR K. pneumoniae isolates
| No. | SAM + CRO
|
SAM + AK
|
AK + LEV
|
SAM + MEM
|
CT + MEM
|
|||||
|---|---|---|---|---|---|---|---|---|---|---|
| FICI | Interpretation | FICI | Interpretation | FICI | Interpretation | FICI | Interpretation | FICI | Interpretation | |
| 1 | 1.75 | Indifference | 2.33 | Indifference | 2.125 | Indifference | 1 | Additive | 2 | Indifference |
| 2 | 1 | Additive | 1.75 | Indifference | 0.52 | Additive | 1 | Additive | 2 | Indifference |
| 3 | 0.2 | Synergism | 2 | Indifference | 2 | Indifference | 1 | Additive | 1 | Additive |
| 4 | 0.2 | Synergism | 0.5 | Synergism | 0.5 | Synergism | 1 | Additive | 2 | Indifference |
| 5 | 0.59 | Additive | 0.3 | Synergism | 1 | Additive | 1.125 | Indifference | 1.3 | Indifference |
| 6 | 2 | Indifference | 1.5 | Indifference | 1.75 | Indifference | 1.2 | Indifference | 1 | Additive |
| 7 | 0.2 | Synergism | 0.4 | Synergism | 1 | Additive | 1 | Additive | 2 | Indifference |
| 8 | 1.5 | Indifference | 2 | Indifference | 1.2 | Indifference | 2 | Indifference | 1.7 | Indifference |
| 9 | 0.7 | Additive | 3 | Indifference | 1.5 | Indifference | 1 | Additive | 2 | Indifference |
| 10 | 0.36 | Synergism | 2 | Indifference | 2 | Indifference | 1 | Additive | 1.6 | Indifference |
| 11 | 0.26 | Synergism | 2 | Indifference | 1.16 | Indifference | 1.16 | Indifference | 2 | Indifference |
| 12 | 0.17 | Synergism | 3.5 | Indifference | 2 | Indifference | 1.16 | Indifference | 1.6 | Indifference |
| 13 | 0.6 | Additive | 1.1 | Indifference | 1 | Additive | 1 | Additive | 2 | Indifference |
| 14 | 0.8 | Additive | 2 | Indifference | 1.1 | Indifference | 0.6 | Additive | 1.25 | Indifference |
| 15 | 1 | Additive | 1 | Additive | 1.3 | Indifference | 1 | Additive | 2 | Indifference |
| 16 | 0.2 | Synergism | 2 | Indifference | 2 | Indifference | 1 | Additive | 1 | Additive |
| 17 | 0.6 | Additive | 1.1 | Indifference | 1 | Additive | 1 | Additive | 2 | Indifference |
| 18 | 0.2 | Synergism | 0.5 | Synergism | 0.5 | Synergism | 1 | Additive | 2 | Indifference |
| 19 | 0.36 | Synergism | 2 | Indifference | 2 | Indifference | 1 | Additive | 1.6 | Indifference |
| 20 | 0.26 | Synergism | 2 | Indifference | 1.16 | Indifference | 1.16 | Indifference | 2 | Indifference |
| 21 | 1 | Additive | 1 | Additive | 1.3 | Indifference | 1 | Additive | 2 | Indifference |
| 22 | 1 | Additive | 1.75 | Indifference | 0.52 | Additive | 1 | Additive | 2 | Indifference |
| 23 | 2 | Indifference | 1.5 | Indifference | 1.75 | Indifference | 1.2 | Indifference | 1 | Additive |
| 24 | 1.5 | Indifference | 2 | Indifference | 1.2 | Indifference | 2 | Indifference | 1.7 | Indifference |
Note: Synergism ≤0.5, additive >0.5–1, indifference >1–4.0, antagonism >4.
Abbreviations: FICI, fractional inhibitory concentration index; MDR, multidrug resistant; K. pneumoniae, Klebsiella pneumoniae; SAM, ampicillin/sulbactam; CRO, ceftriaxone; AK, amikacin; LEV, levofloxacin; MEM, meropenem; CT, colistin.