Fluconazole susceptibility of Italian Candida dabliniensis clinical isolates determined by reference and simplified tests

Candida dubliniensis is an opportunistic pathogen mainly associated with or al candidiasis in human immunodeficiency virus (HIV)-infected individuals. We recently recovered the first Italian clinical isolates of C. dubliniensi s from the oral cavities of seven HIV-seropositive subjects. The in vitro s usceptibility to fluconazole (FLCZ) of these isolates was determined accord ing to the National Committee for Clinical Laboratory Standards (NCCLS) M27 -A broth microdilution method for yeasts. All seven isolates of C. dublinie nsis were susceptible to FLCZ (MICs less than or equal to0.5 mug/ml). Resul ts of this reference method were compared to those obtained with simplified tests, more adapted to routine evaluation in hospital laboratories. Fungit est and Sensititre YeastOne colorimetric microplate-based methods have been evaluated. The agar disk diffusion method has also been tested on two diff erent media: RPMI 1640-2% glucose and High Resolution-2% glucose-0.5 mug/ml methylene blue. All of the simplified methods tested were able to correctl y identify FLCZ-susceptibility of this group of Italian C. dubliniensis iso lates.