Nail Digital Dermoscopy in Onychomycosis: A Correlation with Clinical Type, Gender, and Culture Examination

Abstract

Objective: Onychomycosis (OM) is a common disease that covers both tinea unguium and those remaining cases caused by yeasts, mainly of the Candida and various non-dermatophyte molds. Diagnosis is usually confirmed with direct microscopy and fungal culture. Nail dermoscopy is a non-invasive tool to diagnose various nail disorders and also to avoid time-consuming investigations. The aim of the present study was to determine the dermoscoping findings in OM and to correlate this with clinical type, gender, and culture results. Materials and Methods: This was a cross-sectional study of 100 patients diagnosed with OM according to clinical findings and direct microscopic examination. Nail dermoscopy was performed using a FotoFinder Digital Dermoscope, and images were recorded. A part of the samples was cultured in all patients. Results: The most frequent clinical type was distal lateral subungual onychomycosis (80.0%). The culture was negative in 72.0% of the samples. In the positive group, 48% of Trichophyton rubrum was cultured. The most common dermoscopic findings were longitudinal stria, ruin appearance, and longitudinal leukonychia. In culture-negative samples, irregular termination was most commonly seen. Ruin appearance, brown discoloration, hematoma, and transverse leukonychia, such as brushing, were compatible with total dystrophic OM. Conclusion: Determinative dermoscopic findings for OM, clinical types, and fungus forms were identified. These signs can avoid unnecessary mycology in selected cases.

Keywords

• onychomycosis
• dermoscopy
• toenails
• culture