Synergistic activity of azoles with amiodarone against clinically resistant Candida albicans tested by chequerboard and time-kill methods

Candida albicans is the most common candidal pathogen, causing serious systemic disease in immunocompromised patients. Azoles are widely applied and largely effective; however, they are generally fungistatic and clinically resistant isolates are emerging increasingly. The present study provided in vitro evidence using a chequerboard technique that amiodarone is strongly synergistic with azoles against resistant C. albicans, with mean fractional inhibitory concentration indices of 0.01 and high-percentage synergistic interactions of 1250%. A time-kill study performed by both colony counting and a colorimetric reduction assay confirmed the synergistic interaction, with a >= 2 log(10) decrease in c.f.u. ml(-1) compared with the corresponding azoles alone. These results suggest the possibility of supplementing azoles with amiodarone to treat resistant C. albicans infections.