title: In vitro antifungal susceptibility of Malassezia pachydermatis from dogs with and without skin lesions.
abstract: Canine Malassezia dermatitis is frequently treated with systemic ketoconazole (KTZ) and itraconazole (ITZ). However, no information is available on the antifungal susceptibility to azoles and allilamine of Malassezia pachydermatis isolates from dogs with or without skin lesions. The present study was designed to evaluate the in vitro antifungal susceptibility of M. pachydermatis strains from dogs with or without skin lesions to KTZ, ITZ, miconazole (MICO), fluconazole (FLZ), posaconazole (POS), voriconazole (VOR) and terbinafine (TER) using the Clinical and Laboratory Standards Institute reference Broth Microdilution Method (CLSI M27-A2). The association between the susceptibility to antifungal compounds and the origin of M. pachydermatis, from skin with or without lesions has been also assessed. A total of 62 M. pachydermatis strains from healthy dogs (i.e., Group A=30) or with skin lesions (i.e., Group B=32) were tested. ITZ, KTZ and POS showed the highest activity against M. pachydermatis strains, whereas MICO TER and FLZ the lowest. A higher number of Malassezia resistant strains were registered among isolates from Group B than those from Group A. This study indicates that M. pachydermatis strains were susceptible to ITZ, KTZ, and POS. However, dogs with lesions may harbour strains with low susceptibility to antifungal agents and displaying cross-resistance phenomena to azole. The antifungal therapy in Malassezia infections requires careful appraisal of choice of drugs especially in cases of unresponsiveness to antifungal treatment or recurrent infections.
authors.affiliation: Dipartimento di Sanità Pubblica e Zootecnia, Facoltà di Medicina Veterinaria, Università degli Studi di Bari, Str. prov.le per Casamassima Km 3, 70010 Valenzano, Bari, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Cafarchia
authors.forename: Luciana A
authors.initials: LA
authors.lastname: Figueredo
authors.forename: Roberta
authors.initials: R
authors.lastname: Iatta
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Montagna
authors.forename: Domenico
authors.initials: D
authors.lastname: Otranto
mesh_terms: D000818:Animals; D000935:Antifungal Agents / Q000494:pharmacology*; D003881:Dermatomycoses / Q000382:microbiology / Q000662:veterinary*; D004283:Dog Diseases / Q000382:microbiology*; D004285:Dogs; D015725:Fluconazole / Q000494:pharmacology; D017964:Itraconazole / Q000494:pharmacology; D007654:Ketoconazole / Q000494:pharmacology; D008290:Malassezia / Q000187:drug effects* / Q000302:isolation & purification; D008825:Miconazole / Q000494:pharmacology; D009281:Naphthalenes / Q000494:pharmacology; D011743:Pyrimidines / Q000494:pharmacology; D000077291:Terbinafine; D014230:Triazoles / Q000494:pharmacology*; D065819:Voriconazole
chemical_list: D000935:Antifungal Agents; D009281:Naphthalenes; D011743:Pyrimidines; D014230:Triazoles; D017964:Itraconazole; C101425:posaconazole; D008825:Miconazole; D015725:Fluconazole; D000077291:Terbinafine; D065819:Voriconazole; D007654:Ketoconazole