Table 1.
In vitro activity of polymyxin B and miconazole against Escherichia coli strains
QC strain | Germany | France | Total | |
---|---|---|---|---|
n | 12 | 5 | 17 | |
MIC for polymyxin B (μg/mL) | ||||
Mode | 0.27 | 0.27 | — | 0.27 |
Median | 0.27 | 0.54 | 0.27 | |
IQR | 0.27–0.27 | 1.07–0.27 | 0.54–0.27 | |
Minimum | 0.13 | 0.13 | 0.13 | |
Maximum | 1.07 | 4.30 | 4.30 | |
FICI for polymyxin B and miconazole | ||||
Mode | 0.25 | 0.25 | 0.25, 0.50 | 0.25 |
Median | 0.25 | 0.25 | 0.25 | |
IQR | 0.50–0.25 | 0.50–0.25 | 0.50–0.25 | |
Minimum | 0.06 | 0.06 | 0.06 | |
Maximum | 0.50 | 0.50 | 0.50 | |
P-values | ||||
pc | 0.955 | |||
p<1.0 | 1.3 × 10−4 | |||
p<0.5 | 0.001 |
Abbreviations: FICI, fractional inhibitory concentration index; IQR, interquartile range; MIC, minimal inhibitory concentration; n, number of isolates; pc, P-value for test of FICI grouping by country; p<1.0 and p<0.5, P-values for tests of FICI < 1.0 and FICI < 0.5; and QC, quality control.