086 Terbinafine-resistant dermatophytosis: an emerging global health threat

Fungal skin infections are the most common disease worldwide. Superficial mycoses caused by Trichophyton rubrum and T.interdigitale one of leading causes for patients to seek dermatological care. Terbinafine (TRB), acting through squalene epoxidase (SQLE) inhibition, is drug choice curing both species. However, TRB-resistant cases increasing. Between 2013 2021, we examined TRB-sensitivity in 5435 consecutive strains T. interdigitale testing their growth capacity on Sabouraud’s medium containing TRB. One percent cohort (n= 47) showed reduced TRB sensitivity being able grow this medium. In all these strains, identified mutations within SQLE. SQLE 46 had a point mutation an amino acid substitution at five positions (L393, F397, Q408, F415, H440) strain nine bp deletion. Overall, F397L was common, representing 34% resistant (n=16). We used broth microdilution method, gold standard test susceptibility microorganisms, acquire MICs (minimum inhibitory concentration) strains. Each associated with specific range MICs, varying between 0.015 8.0 μg/ml. The highest were measured L393F mutation, followed F397L. MIC μg/ml already conferred clinical resistance TRB, defining minimum breakpoint predicting failure. Any growing potentially confers resistance. multiple cases, based our data, treatment adapted complete cure achieved using systemic itraconazole or fluconazole. TRB-resistance becoming global health threat. Here, determine its prevalence largest up today, describing detail underlying molecular mechanisms. validate novel which can rapidly reliably identify present experience infections.