Fluconazole zone diameter distributions for all Candida spp Fluconazole zone diameter distributions for all Candida spp.: 79,485 isolates tested against fluconazole. Fluconazole zone diameter distributions for all Candida spp.: 79,485 isolates tested against fluconazole. Isolates were obtained from 115 institutions in 34 countries from 2001 through 2003. Interpretive breakpoints: susceptible (S), ≥19 mm; susceptible-dose dependent (SDD), 15 to 18 mm; resistant (R), ≤14 mm. (Reprinted from reference 75.) M. A. Pfaller et al. Clin. Microbiol. Rev. 2006; doi:10.1128/CMR.19.2.435-447.2006