TABLE 2.

MICs (μg/ml) of antibiotics for C. difficile isolates by using Etest

AntibioticMIC for strain
T-378aÖ99-1670aA177:1aUS1067bUS1165b8864c
Ciprofloxacin>32>32>32>32>32>32
Levofloxacin>32>32>32>32>32>32
Moxifloxacin0.521.0>32>321.0
Clindamycin484424
Metronidazoled0.053 (3)0.125 (3)0.084 (3)0.33 (3)0.25 (3)0.19 (2)
Vancomycin0.50.250.50.50.51.0
  • a Historical Swedish PCR ribotype 027 isolates.

  • b Recent epidemic PCR ribotype 027-pulsed-field gel electrophoresis type NAP1 isolates.

  • c Reference strain (toxin A B+) obtained from CCUG, Göteborg, Sweden.

  • d Averages of independent experiments (the number of experiments is indicated in parentheses). Means were 0.088 and 0.31 μg/ml for the historical and epidemic isolates, respectively (P = 0.015 [t test using unequal variance]).