Causative fungi of tinea corporis and tinea cruris lesions were investigated using the adhesive tape sampling method in a dermatology clinic in Isahaya, Nagasaki prefecture in Japan from 2011 to 2022. A total of 254 strains were isolated, including Microsporum canis, 49 (male, 7; female, 42); Trichophyton tonsurans, 39 (male, 31; female, 8); Trichophyton rubrum, 73 (male, 42; female, 31); and others (18), indicating a 70.5% positivity rate.
　M. canis was isolated mostly from children and aged females suggesting infection from contact with pet animals. T. tonsurans was isolated almost exclusively from young contact sports players, reflecting the recent epidemic of this fungus throughout Japan. T. rubrum is the most important dermatophyte species in Japan. In this survey, T. rubrum was identified most in both sexes and in all generations, but relatively higher in older males.
　These results agree with the epidemiological data published from a survey of patients who visited hospitals in Japan. The tape sampling method is easy to use and has been proven effective for collecting samples of the causative fungi by primary care physicians in combination with mycological laboratories.

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　Dermatophytosis caused by Trichophyton indotineae has been recorded in Japan since 2020, and there is concern that it may spread further in the country. This paper explains the isolation, identification, and drug resistance mechanisms of the fungus, as well as the status of isolation in Japan and overseas, to serve as reference in dermatological practice. Skin debris, crusts of the affected area, or other samples are inoculated onto dermatophyte isolation media such as a Mycocel agar in accordance with standard isolation methods. Colonies on Mycocel agar and Sabouraud’s dextrose agar are white to pale yellowish brown, flat, with short-villous or powdery surface, and closely resemble those of Trichophyton interdigitale. Therefore, its identification is based on clinical findings (extensive tinea corporis), urease testing (negative reaction), and sequencing of the ribosomal internal transcribed spacer (ITS) region of the isolate. ITS region homology can be determined by performing a Basic Local Alignment Search Tool (BLAST) search at the National Center for Biotechnology Information (NCBI) site. Its identity can be confirmed if the result is a 100% match with the registered T. indotineae sequences. T. indotineae has been isolated in several locations in Tohoku, Kanto, and Kyushu. Although most of the patients are foreign nationals, the fungus has now been isolated also from Japanese who have no history of overseas travel. Public health guidance must be issued, especially because of the possibility of infection from common items and facilities that may also be used by travelers from overseas.

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