In vitro effects of Ag+ on planktonic and adhered cells of fluconazole-resistant and susceptible strains of Candida albicans, C. glabrata and C. krusei

Planktonic and attached cells of strains of Candida albicans, C. glabrata and C. krusei with varied susceptibilities to fluconazole (FCZ) were compared for their relative susceptibilities to Ag+ via cell recovery and flow cytometric analyses. All strains lost membrane permeability and were non-recoverable upon culture after 1 h exposure in morpholino-ethanesulfonic acid (MES) buffer fortified with ⩽2.0 μg/ml Ag+. Cells attached to silicone over a 2-h period demonstrated enhanced tolerance to FCZ and to a lesser degree to Ag+. Minimal inhibitory concentrations of Ag+ in defined media increased in the order C. glabrata, C. krusei, C. albicans. Susceptibilities to Ag+ did not correlate with tolerance or resistance to FCZ.