Prevalence of Onychomycosis Among Patients with Nail Psoriasis Who Are Not Receiving Immunosuppressive Agents: Results of a Pilot Study

Nail psoriasis and onychomycosis can often be hard to differentiate clinically and may coexist, complicating each other's course. The aim of this study was to determine the prevalence of onychomycosis among patients with nail psoriasis not being treated with immunosuppressive agents, which constitute an independent risk factor for fungal infections. A cross-sectional study was performed. All adult patients with nail psoriasis who were not receiving antifungal and/or immunosuppressive treatment were recruited at the 2nd University Dermatology Department of Aristotle University of Thessaloniki from 10/2016 till 02/2017. If onychomycosis was clinically suspected, nail samples were collected and direct microscopy with 15% KOH solution and culture were performed. Target-NAPSI and DLQI score were also calculated. Of the 23 patients recruited, 20 were men and 3 were women, with a mean age of 53.43 years (48.25, 58.62), a mean target-NAPSI score of 10.72 (9.62, 11.77) and a mean DLQI score of 10.17 (7.46, 12.89). A total of 34.78% of patients tested positive for onychomycosis. Yeast were isolated in 37.50% of cases, non-dermatophyte filamentous fungi in 37.50% and T. rubrum in 12.50%. The prevalence of onychomycosis among nail psoriasis patients is higher than that among the general population of Greece (15%-20%). Yeast and moulds predominate in infection cases of nail psoriasis patients.