Table 3.
Antimicrobials susceptibility of 344 invasive Listeria monocytogenes isolates collected from 1997 to 2013 in Poland.
| Antimicrobials | MIC (µg/ml) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1997–2013 n = 344 | 1997–2004 n = 36 | 2005–2008 n = 74 | 2009–2010 n = 86 | 2011–2013 n = 148 | MIC breakpoints | |||||
| percentage of susceptibled | range | MIC50 | MIC90 | MIC90 | MIC90 | MIC90 | MIC90 | S≤ | R> | |
| Ampicillina | 100 (14%) | 0.02–1 | 0.5 | 1 | 1 | 1 | 1 | 0.5 | 1 | 1 |
| Penicillina | 100 (4.7%) | 0.06–1 | 0.25 | 0.5 | 0.5 | 0.5 | 1 | 0.25 | 1 | 1 |
| Meropenema | 100 (1.2%) | 0.03–0.25 | 0.06 | 0.12 | 0.12 | 0.12 | 0.12 | 0.12 | 0.25 | 0.25 |
| Erythromycina | 100 | 0.06–0.5 | 0.25 | 0.5 | 0.25 | 0.25 | 0.25 | 0.5 | 1 | 1 |
| Co-trimoxazolea | 100 (10%) | 0.01–0.06 | 0.03 | 0.06 | 0.03 | 0.03 | 0.03 | 0.06 | 0.06 | 0.06 |
| Levofloxacinb | 100 | 0.12–1 | 0.5 | 1 | 0.5 | 0.5 | 0.5 | 1 | 2 | 2 |
| Gentamicinc | 100 | 0.03–0.5 | 0.06 | 0.25 | 0.06 | 0.06 | 0.06 | 0.5 | 1 | 1 |
| Vancomycinc | 100 | 0.25–1 | 0.5 | 0.5 | 0.5 | 0.5 | 0.5 | 0.5 | 2 | 2 |
| Tetracyclinec | 99.5 | 0.12–64 | 0.5 | 1 | 1 | 1 | 1 | 0.5 | 1 | 2 |
| Rifampicinb | 100 | 0.01–0.25 | 0.06 | 0.12 | 0.12 | 0.12 | 0.12 | 0.06 | 0.06 | 0.5 |
n, Number of isolates. aInterpretation according to the EUCAST clinical breakpoint value specific for L. monocytogenes48. bInterpretation according to the EUCAST clinical breakpoint value for Streptococcus pneumoniae48. cInterpretation according to the EUCAST clinical breakpoint value for Staphylococcus spp.36,48. dIn brackets % of susceptible isolates with borderline MIC breakpoint values.