Revival of favus in Japan caused by Trichophyton schoenleinii

Favus is a type of dermatophytosis known to produce yellow scutula around hair follicles. Most cases of this disease worldwide are infections of Trichophyton schoenleinii. Favus has rarely been reported in Japan throughout the last four decades, and T. schoenleinii has not been clinically isolated in any case during the period. Here, we report a case of favus of vellus hair observed in a 63-year-old Japanese woman. Fungal culture showed negative; however, we detected fungal elements in the crust and hair bulbs by Grocott staining. Pathogenic fungi were identified as T. schoenleinii by polymerase chain reaction-based DNA sequencing, targeting the internal transcribed spacer regions of the rRNA gene using the formalin-fixed, paraffin-embedded tissue sample. She was successfully treated with p.o. administration of terbinafine and topical application of luliconazole cream.