Molecular epidemiology and antifungal susceptibility of dermatophytes and Candida isolates in superficial fungal infections at a grade A tertiary hospital in Northern China

Abstract This study analyzed the prevalence and antifungal susceptibility of superficial fungal infections in 295 cases from 2019 to 2020 at a dermatology clinic. Dermatophytes were the predominant pathogens (69.5%), including Trichophytonrubrum, T. interdigitale, Microsporum canis, et al., followed by Candida spp. (29.5%), including Candidaalbicans, Ca. parapsilosis, and Ca. glabrata. The most common infections were onychomycosis (36.3%), tinea cruris (30.5%), and tinea corporis (18.6%). The distribution of SFI types showed variations based on gender, age, and season. Common antifungal agents, including terbinafine, voriconazole, ciclopiroxamine, amphotericin B, itraconazole, and ketoconazole have exhibited low minimum inhibitory concentrations against dermatophytes, especially terbinafine, which has been potent against superficial fungal infections caused by dermatophytes in the local area. Candida spp. strains were generally susceptible or classified as wild-type to 5-flucytosine and amphotericin B, with 92.0% being wild-type for itraconazole. However, resistance to fluconazole and voriconazole was observed in a small percentage of Ca. albicans and Ca. parapsilosis strains. The emergence of drug-resistant Candida underscores the importance of prudent antifungal use and continuous surveillance.