Fluconazole disk diffusion susceptibility testing of Candida species

• Published in: Journal of clinical microbiology Vol. 36; no. 11; pp. 3429 - 3432
• Main Authors: KIRKPATRICK, W. R, TURNER, T. M, FOTHERGILL, A. W, MCCARTHY, D. I, REDDING, S. W, RINALDI, M. G, PATTERSON, T. F
• Format: Journal Article
• Language: English
• Published: Washington, DC American Society for Microbiology 01.11.1998
• Series: Note
• Subjects: AIDS-Related Opportunistic Infections - drug therapy; AIDS-Related Opportunistic Infections - microbiology; Antibiotics. Antiinfectious agents. Antiparasitic agents; Antifungal agents; Antifungal Agents - pharmacology; Biological and medical sciences; Candida; Candida - drug effects; Candida - isolation & purification; Candida albicans - drug effects; Candida albicans - isolation & purification; Candidiasis - complications; Candidiasis - drug therapy; Candidiasis - microbiology; Drug Resistance, Microbial; Evaluation Studies as Topic; Fluconazole - pharmacology; Humans; Medical sciences; Microbial Sensitivity Tests - methods; Microbial Sensitivity Tests - statistics & numerical data; Mycology; Mycology - methods; Mycology - statistics & numerical data; Pharmacology. Drug treatments; Sensitivity and Specificity; Fungi; Antifungal agent; Yeast; Fluconazole; Drug susceptibility test; Candida; Minimum inhibitory concentration; Triazole derivatives; Fungi Imperfecti; Thallophyta
• ISSN: 0095-1137; 1098-660X
• DOI: 10.1128/jcm.36.11.3429-3432.1998

We describe a simple procedure for detecting fluconazole-resistant yeasts by a disk diffusion method. Forty clinical Candida sp. isolates were tested on RPMI-glucose agar with either 25- or 50-microgram fluconazole disks. With 25-microgram disks, zones of inhibition of >/=20 mm at 24 h accurately identified 29 of 29 isolates for which MICs were </=8 microgram/ml, and with 50-microgram disks, zones of >/=27 mm identified 28 of 29 such isolates. All 11 isolates for which MICs were >8 microgram/ml were identified by using either disk. Disk diffusion may be a useful screening method for clinical microbiology laboratories.