In vitro activities of azole antifungal agents against Propionibacterium acnes isolated from patients with acne vulgaris.

The Gram-positive bacterium Propionibacterium acnes is the causative agent of acne vulgaris. Antibiotics such as tetracycline and macrolide derivatives are used to treat this skin disease; however, the isolation frequency of antibiotic-resistant P. acnes has been increasing. The anti-P. acnes activity of imidazole antifungal agents was reported more than 20 years ago, and since then, new azole antifungal agents have been marketed. Thus, this study determined the in vitro activities of azole antifungal agents against P. acnes isolated from patients with acne vulgaris. Of the five agents tested, miconazole, ketoconazole, and itraconazole showed concentration-dependent anti-P. acnes activity, including against antibiotic-resistant isolates. Time-kill assay also showed the time-dependent activity of the drugs. Fluconazole and voriconazole showed no anti-P. acnes activity.