title: An azole-resistant isolate of Malassezia pachydermatis.
abstract: Canine Malassezia dermatitis (MD) is frequently treated with systemic ketoconazole (KTZ) and itaconazole (ITZ). However, the antifungal susceptibility of clinical isolates of M. pachydermatis from dogs and cats to the azoles has not been well investigated. In the present study, the in vitro susceptibility of the standard strain (CBS1879: the neotype strain of M. pachydermatis) and 29 clinical isolates of M. pachydermatis to the azoles was measured by a modified CLSI M27-A2 test using modified Dixon medium as well as by the E-test. The minimum inhibitory concentrations (MICs) of the 30 isolates of M. pachydermatis (including the neotype strain) against KTZ and ITZ were <0.03 μg/ml by the two methods. The MICs of 1 clinical isolate (ASC-11) were 1 and 2 μg/ml against KTZ, and 2 and 8 μg/ml against ITZ, by the modified CLSI M27-A2 test and the E-test, respectively. Thus, isolate ASC-11 may be resistant to these azoles, making this the first report of a resistant isolate of M. pachydermatis to KTZ and ITZ.
authors.affiliation: Department of Pathobiology, Nihon University School of Veterinary Medicine, 1866 Kameino, Fujisawa, Kanagawa 252-8510, Japan.
authors.forename: Misako
authors.initials: M
authors.lastname: Nijima
authors.forename: Rui
authors.initials: R
authors.lastname: Kano
authors.forename: Masahiko
authors.initials: M
authors.lastname: Nagata
authors.forename: Atsuhiko
authors.initials: A
authors.lastname: Hasegawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kamata
mesh_terms: D000818:Animals; D000935:Antifungal Agents / Q000494:pharmacology*; D002415:Cats; D004285:Dogs; D025141:Drug Resistance, Fungal; D017964:Itraconazole / Q000494:pharmacology*; D007654:Ketoconazole / Q000494:pharmacology*; D008290:Malassezia / Q000187:drug effects* / Q000302:isolation & purification; D008826:Microbial Sensitivity Tests
chemical_list: D000935:Antifungal Agents; D017964:Itraconazole; D007654:Ketoconazole