A Case of Tinea Pseudoimbricata Due to Trichophyton tonsurans Induced by Topical Steroid Application.

Tinea imbricata and tinea pseudoimbricata are variant types of tinea corporis characterized by annual-ring-shaped erythema. Although the skin lesions manifest similar symptoms, these two diseases are classified based on causative fungi. The former is caused by Trichophyton concentricum, an anthropophilic dermatophyte, and the latter is caused by dermatophytes other than T. concentricum, commonly zoophilic fungi such as Trichophyton mentagrophytes complex. Here, we report a 27-year-old Japanese male diagnosed with tinea pseudoimbricata attributed to Trichophyton tonsurans, an anthropophilic dermatophyte. We suspected that application of steroid ointment caused the annular pattern of his skin lesions. After three months use of topical luliconazole cream, treatment was finished. We also summarize the knowledge about tinea pseudoimbricata through previous reports with bibliographical consideration.

A Case of an Ex Vivo Onychomycosis Model Introduced with a Cultured Colony of Kocuria koreensis from a Diabetic Ingrown Toenail.

A 57-year-old male patient with >10-year history of type 2 diabetes presented with a left big toenail deformity and pain. A physical examination revealed a white and yellow-to-brown patch on the nail as well as thickening and ingrowth of the nail plate. The nail plate was opened using nippers, and a fungal culture revealed Trichophyton interdigitale with yellow yeast. The yeast isolate was identified as Kocuria koreensis, a Gram-positive aerobic coccoid with keratinolytic properties that is part of the normal flora of the skin. We created an ex vivo onychomycosis model of T. interdigitale infection of the human nail by placing a sterilized normal nail on the cultured slant. K. koreensis initially spread over the normal nail, and T. interdigitale then penetrated the nail plate. After one year and six months, a spiral ingrown nail developed. A histopathological examination of the spiral revealed onychomycosis with superficial and deep abscesses of Gram-positive cocci infection. We performed PCR from paraffin-embedded material, and the sequences obtained were identical to those of T. interdigitale and K. koreensis. These results suggest that the development of onychomycosis by T. interdigitale is introduced and accelerated by K. koreensis, and the symbiosis of these microorganisms is suspected in the nail. This ex vivo model has a number of limitations. Therefore, further research on co-infected cases is needed to confirm this hypothesis.

A Case of Tinea Faciei, Tinea Corporis, and Tinea Unguium with Dermatophytoma Successfully Treated with Oral Fosravuconazole L-lysine Ethanolate.

We present a 76-year-old Japanese male with tinea faciei, tinea corporis, and tinea unguium with dermatophytoma. We performed fungal culture and confirmed the causative fungus to be Trichophyton rubrum. We treated the patient using oral fosravuconazole l-lysine ethanolate (F-RVCZ). More than one year has passed since the end of treatment, but there has been no recurrence. This case suggests that F-RVCZ is effective for tinea other than tinea unguium.