TABLE 1.

Comparison of ranges, MIC50s, MIC90s, and percentages of gatifloxacin- and ciprofloxacin-susceptible mycobacteria

Species and drugNo. of isolates testedbMIC (μg/ml)a% Suscep- tible
Range50%90%
M. abscessus 24
    Gatifloxacin2->3216>3210
    Ciprofloxacin8->1616>160
M. chelonae 32
    Gatifloxacin≤0.12-81496
    Ciprofloxacin0.25->164>168
M. fortuitum group39
    Gatifloxacin≤0.12-0.5≤0.12≤0.12100
    Ciprofloxacin≤0.12-20.251100
M. mucogenicum 20
    Gatifloxacin≤0.12-0.5≤0.25≤0.25100
    Ciprofloxacin≤0.25-10.50.5100
  • a The MIC resistance breakpoints were ≥8 μg/ml for gatifloxacin and ≥4 μg/ml for ciprofloxacin (6, 7).

  • b A total of 115 isolates were tested.