Antifungal activities of tacrolimus in combination with antifungal agents against fluconazole-susceptible and fluconazole-resistant Trichosporon asahii isolates

作者：Kubica Thais Felli; Denardi Laura Bedin; Azevedo Maria Isabel; Oliveira Vanessa; Severo Luiz Carlos; Santurio Janio Morais; Alves Sydney Hartz^*

来源：Brazilian Journal of Infectious Diseases, 2016, 20(6): 539-545.

DOI：10.1016/j.bjid.2016.08.008

• Susceptibility
• FK506
• Resistance
• Synergism

The antifungal activity of tacrolimus in combination with antifungal agents against different fungal species has been previously reported. Here we report the in vitro interactions between tacrolimus and amphotericin B, fluconazole, itraconazole, and caspofungin against 30 clinical isolates of both fluconazole-susceptible and fluconazole-resistant Trichosporon asahii. For these analyses, we used the broth microdilution method based on the M27-A3 technique and checkerboard microdilution method. Tacrolimus showed no activity against T. asahii strains (minimal inhibitory concentrations, MICs > 64.0 mu g mL(-1)). However, a larger synergistic interaction was observed by the combinations tacrolimus + amphotericin B (96.67%) and tacrolimus + caspofungin (73.33%) against fluconazole-susceptible isolates. Combinations with azole antifungal agents resulted in low rates of synergism for this group (fluconazole + tacrolimus = 40% and itraconazole + tacrolimus = 10%). Antagonistic interactions were not observed. For the fluconazole-resistant T. asahii group, all tested combinations showed indifferent interactions. The synergism showed against fluconazole-susceptible T. asahii isolates suggests that the potential antifungal activity of tacrolimus deserves in vivo experimental investigation, notably, the combination of tacrolimus with amphotericin B or caspofungin.

• 出版日期2016-12