Molecular identification and antifungal susceptibility of clinical fungal isolates from onychomycosis (uncommon and emerging species)

Onychomycosis is a common nail problem, accounting for up to 50% of all nail diseases. The aim of the present study was to determine the species distribution based on the restriction fragment length polymorphism and susceptibility patterns of the causative agents of onychomycosis. This cross-sectional study was conducted on nail samples collected from 257 patients suspected of onychomycosis during 14 months. Fungal isolates were identified by polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP) with the enzymes Msp I, Mva I, Alw I and sequencing. According to the results, out of the 257 patients participating in the study, onychomycosis was diagnosed in 180 (70.03%) cases, among which 51.1% were caused by non-dermatophyte moulds (NDMs), 35% by yeast and 10.6% by dermatophytes. Numerous cryptic species recovered from onychomycosis for the first time. In the majority of cases, novel triazoles and imidazoles (ie, efinaconazole, luliconazole and lanoconazole) showed potent activity in comparison with other antifungal agents. The minimum inhibitory concentration (MIC) of luliconazole and lanoconazole ranged within 0.001 to >1 mu g/mL and their geometric mean MICs were 0.0154 and 0.0309 mu g/mL against all isolates, respectively. It seems that obtained data will be useful to improve the knowledge of researchers, clinicians and dermatologists about onychomycosis distribution, species diversity and adoption of appropriate treatment.