Onychomycosis, a fungal infection affecting the nails, accounts for approximately 50% of nail disorders and up to 30% of cutaneous fungal infections worldwide. It is mainly caused by dermatophytes ( Trichophyton rubrum ), yeasts ( Candida spp.), and non-dermatophyte fungi ( Fusarium , Aspergillus ). This condition is associated with factors such as advanced age, diabetes, immunosuppression, and prolonged exposure to moisture. Despite its high prevalence, accurate diagnosis and effective treatment remain challenging due to fungal resistance and frequent recurrence. This review evaluated the effectiveness of diagnostic methods (microscopy, culture, and PCR) and therapeutic approaches (topical antifungals, oral antifungals, and combination therapy) for onychomycosis, considering cure rates, recurrence, and adverse effects. A total of 45 studies published between 2013 and 2023 were analyzed, retrieved from PubMed, Embase, and Cochrane databases. Randomized clinical trials, systematic reviews, and cohort studies comparing treatments and diagnostic methods were included. Data were stratified by etiologic agent and severity of infection. Conventional diagnostic methods (KOH and culture) showed moderate sensitivity (50–70%), whereas molecular techniques (PCR) achieved 85–95% accuracy, albeit at higher cost. Regarding treatment, oral terbinafine demonstrated the highest efficacy against dermatophytes (70–80% cure rate), followed by itraconazole (60–70%). For Candida spp., fluconazole was superior (65% cure rate). Topical formulations (ciclopirox, amorolfine) showed limited efficacy (20–40%), except in superficial infections. Combination therapy (oral + topical + laser) increased cure rates to 85–90% and reduced recurrence. Gastrointestinal adverse effects and hepatotoxicity were reported in 5–10% of patients using oral antifungals. Onychomycosis remains a challenging infection, requiring accurate diagnosis—prioritizing PCR in recalcitrant cases—and a personalized therapeutic approach. Oral terbinafine is first-line therapy for dermatophytes, while combined therapies with topical agents or laser improve outcomes. Preventive strategies, such as proper foot drying and avoiding the sharing of nail clippers, are essential to reduce recurrence. Future studies should explore new antifungal agents and reduced-dose regimens to minimize adverse effects.
Marchelli et al. (2026) studied this question.