Trichophyton bullosum is a zoophilic dermatophyte from the Arthroderma benhamiae complex with a poorly known distribution. In this study, we report a case of dermatophytosis caused by T. bullosum in a 6-year-old male horse who had a skin lesion located in a saddle area. The infection spread rapidly to the upper chest and to both sides of the trunk. The dermatophyte was isolated in culture and identified by sequence analysis of the internal transcribed spacer regions (ITS rDNA). To date, this is the first verified case of animal infection due to T. bullosum in Europe following the 2012 report of human infection in France. We hypothesize that this species can be relatively common in horses and donkeys, but it is confused with other zoophilic species responsible for infections with similar clinical manifestations, and when isolated in culture, it is misidentified as the phenotypically similar T. verrucosum. Previous cases of dermatophytosis caused by T. verrucosum-like dermatophytes in horses and donkeys were reviewed together with human infections transmitted from these animals. This summary estimates possible distribution width of T. bullosum. The taxonomy of T. verrucosum-like dermatophytes is extremely difficult due to lack of original material and poor morphology of species. Molecular genetic methods are necessary to verify the identification of these fungi. ITS1 or ITS2 region of rDNA alone is sufficient for correct identification.

• Keywords
• Arthroderma benhamiae complex, Enilconazole, Flutrimazole, Horse diseases, Superficial mycoses, Zoonotic infections,
• MeSH
• DNA, Fungal chemistry   genetics   MeSH
• Phylogeny MeSH
• Horses MeSH
• DNA, Ribosomal Spacer chemistry   genetics   MeSH
• Molecular Sequence Data MeSH
• Mycological Typing Techniques MeSH
• Horse Diseases diagnosis   microbiology   pathology   MeSH
• Sequence Analysis, DNA MeSH
• Cluster Analysis MeSH
• Tinea diagnosis   microbiology   pathology   veterinary   MeSH
• Trichophyton classification   genetics   isolation & purification   MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Case Reports MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Europe MeSH
• Names of Substances
• DNA, Fungal MeSH
• DNA, Ribosomal Spacer MeSH