Diagnosis and Treatment of Onychomycosis in Psoriasis Patients: A Single-Center Cohort Study

Literature on onychomycosis prevalence, causative agents, and systemic antifungal treatment efficacy in psoriasis are sparse.

The objectives of the study were to determine onychomycosis prevalence in psoriasis patients with nail changes and to evaluate the efficacy and safety of 2 systemic antifungal treatments, terbinafine, and fluconazole.

Records from the Division of Dermatology at Rabin Medical Center (2012-2022), were retrospectively analyzed, including nail samples from consecutive psoriasis patients referred to the institutional mycological laboratory.

One hundred thirty-nine psoriasis patients with suspected onychomycosis were referred for mycological testing (46.8% female, median age 62 years), onychomycosis was diagnosed in 67.6% of cases. Fifty-one point one percent of patients were on systemic psoriasis treatments, 60.6% of them receiving biologic therapies. Trichophyton rubrum was the most prevalent (81.3%) isolated fungi of all positive cultures. Fifty-one patients received systemic antifungal treatment, with 47.1% receiving terbinafine and 52.9% fluconazole. Clinical improvement was observed in 70.8% of terbinafine-treated cases and 40.7% of fluconazole-treated cases (P = .002). No psoriasis flare-ups were attributed to systemic antifungal treatment.

This cohort provides insights into prevalence of onychomycosis, and the efficacy and safety of systemic antifungal treatment in psoriasis patients, including patients on biologic therapies. Further prospective studies are recommended.