Cluster Infection Caused by a Terbinafine-resistant Dermatophyte at a Group Home: The First Case Series in Japan
Hiromitsu Noguchi, Tadahiko Matsumoto, Masataro Hiruma, Utako Kimura, Kayo Kashiwada‐Nakamura, Masahide Kubo, Takashi Yaguchi, Satoshi Fukushima, Rui Kano
Abstract
Terbinafine, which targets squalene epoxidase (SQLE), has been used to treat dermatophyte infections for approximately 30 years. In 2017, a Swiss study reported that 1% (16/1,644) of Trichophyton rubrum and 0.2% (1/412) of T. interdigitale were resistant to terbinafine (1). In 2019, we presented the first Japanese case of tinea unguium caused by a terbinafine-resistant T. rubrum isolate (Phe397Leu substitution), which was deposited as IFM 65760 (2). Our clinic obtained 3 terbinafine-resistant T. rubrum strains (Leu393Phe substitution) from 95 dermatophyte clinical isolates including T. rubrum (n = 62) and T. interdigitale (n = 33) in June 2020 (3). One strain (T. rubrum N79) was derived from a group home for individuals with intellectual disabilities. In this study, we examined the residents of this facility using mycological and molecular techniques to detect terbinafine-resistant T. rubrum strains.