Abstract
To confirm preliminary interpretive breakpoints for prototype 5 µg levofloxacin disks, 490 strains were tested in vitro using commercially manufactured disks. For in vitro susceptibility testing, 5 µg levofloxacin disks can be used with interpretive criteria of ≤ 12 mm for resistant (MIC ≥ 8.0 µg/ml) and ≥ 16 mm for susceptible (MIC ≤ 2.0 µg/ml). Proposed quality control limits for tests of levofloxacin are as follows:Escherichia coli ATCC 25922, zones 29–37 mm or MIC 0.008–0.03 µg/ml;Pseudomonas aeruginosa ATCC 27853, zones 19–26 mm or MIC 0.5–2.0 µg/ml;Staphylococcus aureus ATCC 25923, zones 24–31 mm;Staphylococcus aureus ATCC 29213, MIC 0.06–0.25 µg/ml andEnterococcus faecalis ATCC 29212, MIC 0.25–2.0 µg/ml.
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Barry, A., Fuchs, P., Tenover, F. et al. Interpretive criteria and quality control for antimicrobial susceptibility tests of levofloxacin. Eur. J. Clin. Microbiol. Infect. Dis. 13, 822–826 (1994). https://doi.org/10.1007/BF02111343
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DOI: https://doi.org/10.1007/BF02111343