Multilocus microsatellite typing was performed on 124 strains of Microsporum canis, which is the most prevalent causative fungus of zoonotic dermatophytosis, isolated in Japan between 1974 and 1981. The strains had been enclosed in glass ampoules by freeze dried process. Genotypes were detected by capillary electrophoresis targeted on six microsatellite regions, and 19 genotypes were found among these 124 strains. The most frequent genotype, which had been reported as genotype L in a previous study, comprised 56 of the 124 strains (45.2%), although genotype L was reported to comprise only six of 165 strains (3.6%) isolated between 2010 and 2017. A decrease in the prevalence of genotype L may have led to the retreat of M. canis infection in 1996 to 2006. On the other hand, genotype A, the second most predominant genotype in the aforementioned studies of strains isolated between 2010 and 2017, comprised just four of 124 strains (3.2%) in the present study. Thus, these studies reveal that prevalences of some major genotypes have changed over the last 40 years. Genotype consistency of strains was proven in all of 12 familial cases, each of which was infected with a single genotype. We emphasize the importance of fungal culture collection for further studies with new techniques in the future.

Candida is a resident of the gastrointestinal tract, mucous membranes, and skin. The main causative species of candidiasis is Candida albicans, but C. glabrata, C. parapsilosis, C. tropicalis, C. krusei, or C. dubliniensis may be involved. 1 We encountered a case of oral candidiasis that developed during treatment for psoriatic arthritis with human monoclonal antibody against human interleukin (IL)-23p19. In this case, two species of fungi, C. dubliniensis and C. glabrata, were isolated in culture, which was considered unique.

Trichophyton tonsurans, an anthropophilic dermatophyte, causes dermatophytosis such as tinea corporis showing erythema with/ without central healing tendency, tinea capitis showing black dots, scaliness, hair loss and purulent follicular inversion known as kerion celsi, and tinea unguium. Large scale studies have reported that cultural practices influence the transmission of particular mycoses, with more than 95% of tinea capitis infections caused by T. tonsurans. 1,2 In Japan, an epidemic has been ongoing among contact sports athletes since the early 2000s. 3,4 Mycological surveys conducted by the Japanese Society for Medical Mycology revealed a nationwide spread of T. tonsurans infection among school judo, wrestling, and sumo teams. [5][6][7][8] Oral terbinafine (TBF) and itraconazole (ITZ) are recommended to treat this infection. 9 However, there are patients who remain uncured or are re-infected after treatment; therefore, the possibility of the presence of drug-resistant isolates is of great dermatological interest.We conducted screening for T. tonsurans infection among groups engaged in contact sports around the year 2000 to inform prevention of an epidemic. [10][11][12][13] We reported the trend of infection by the pathogen, and examined molecular types of isolates using restriction enzyme fragment length polymorphism (RFLP) in the nontranscription spacer (NTS) region of ribosomal RNA gene in years 2000 and 2015. [10][11][12][13] In the present study, we discuss the 20-year trend of T. tonsurans infection in Japan. During the past two decades,

Neoscytalidium dimidiatum is a common fungus that causes non-dermatophyte dermatomycosis in tropical regions, but there have been no reports of infection with N. dimidiatum in Japan. Here, we report the first isolation of N. dimidiatum from human dermatomycosis in Japan. A 62-year-old healthy Japanese male had been treated with oral terbinafine for tinea pedis diagnosed from a microscopic examination in 2003 with a lesion that was intractable. In 2020, re-identification by sequencing the internal transcribed spacer regions and the D1/D2 domain of the large-subunit (LSU) ribosomal RNA gene revealed that the pathogen was N. dimidiatum. Antifungal susceptibility tests showed that the minimum inhibitory concentration of the drug luliconazole (LLCZ) against the pathogen was 0.00049 µg/mL. The patient's lesions were cured by topical LLCZ. The clinical course and drug susceptibility suggest that LLCZ is a suitable first-line drug for treatment.

Trichophyton tonsurans is a major causative fungus of human dermatophytosis, which has been isolated from contact sport players in Japan. The microbiome in the scalp of judoists with or without T. tonsurans infection was analyzed to investigate the correlation between T. tonsurans infection and microbiome profile. Among 30 members of the same judo team in a high school, samples were collected by scrubbing their scalp with shampoo hairbrushes; then, DNA was extracted directly from the obtained scales. Twenty‐seven datasets were subjects for microbiome analysis and T. tonsurans was detected in six members (no T. tonsurans‐positive participants had scalp lesions). Regarding the fungal microbiome, Cyphellophora were more abundant in the T. tonsurans‐positive group (TP) than T. tonsurans‐negative group (TN) (P < 0.05). Regarding the Malassezia microbiome, Malassezia caprae were more abundant in TP than TN (P < 0.01). Regarding the bacterial microbiome, Lactococcus, Actinobacillus, Beijerinckiaceae and Xanthomonas were more abundant in TP than TN (P < 0.05). Also, the Shannon diversity index revealed no significant diversity between TP and TN, and 3‐D principal coordinate analysis revealed no clear separation between TP and TN. There was practically no difference in microbiome between TP and TN, indicating that T. tonsurans could colonize humans regardless of their original microbiome. T. tonsurans coexisted with other fungi and bacteria without affecting species diversity in asymptomatic carriers. To our knowledge, this is the first investigation of the correlation between T. tonsurans infection and microbiome profile.