Prevalence of onychomycosis among psoriasis patients: a clinico-mycological and dermoscopic comparative cross sectional study

Onychomycosis, a nail infection caused by dermatophytes, yeast, and molds makes up roughly half of all onychopathies and is the most prevalent nail condition in the world.

Clinically, nail psoriasis and onychomycosis can frequently be difficult to distinguish from one another.

To assess the prevalence of onychomycosis in patients with psoriasis.

Fifty patients with psoriasis associated with nail disease were included in this study.

After taking clinical history, nail samples were gathered for dermoscopic inspection, culture, direct microscopy with 20% KOH solution, and nail clipping with PAS stain.

Of the 50 patients recruited, 43 were males and 7 were females, with mean age 6–71 years (mean ± SD 44.06 ± 16.2).

Eleven patients (22%) tested positive for onychomycosis.

Dermatophytes were isolated from 2% of patients, yeast from 14% of patients, and non-dermatophytic mold from 38% of patients.

Histopathological results revealed fungal hyphae and spores in 18% of patients.

The most prevalent dermoscopic sign in psoriatic patients with onychomycosis was spikes (81.8%) with statistical significance (P-value < 0.001), while nail pitting was the most prevalent dermoscopic feature in nail psoriasis.

This study lays the way for an accurate diagnosis of nail lesions by highlighting the significance of cooperation between mycology, histology, and dermoscopy in the diagnosis of onychomycosis in patients with nail psoriasis.