Onychoscopy in the diagnosis of the distal subungual onychomycosis and traumatic onycholysis

Abstract

Aim: Distal subungual onychomycosis is a common public health problem which composes a large part of nail diseases. The exact diagnosis of the disease is often unfeasible without mycological investigations. In this study, we aimed to reveal sensitivity and specificity of previously described onychoscopic (nail dermoscopic) features that support and facilitate diagnosis of distal subungual onychomycosis. Material and Methods: Big toe nail of 53 patients who present with distal onycholysis were examined by digital dermatoscopy and were photographed. Specific dermatoscopic features were recorded. Mycological investigations were performed in all patients and dermatoscopic diagnosis was compared with mycological diagnosis. Three patients were excluded from the study whose final diagnoses were psoriasis. Results: Two specific findings previously described as longitudinal stria and spike were obtained as a result of examination of the dermatoscopic imaging. Sensitivity and specificity of longitu-dinal stria sign was found as 75.7% and 88.2% respectively. Sensitivity and specificity of spike sign was found as 57.5% and 94.1% respectively. And finally sensitivity and specificity of the presence of at least one of the two signs was found as 96,9% and 88,2%, respectively. Conclusion: Dermoscopic examination is very useful and cost-effective method in diagnosis of the distal subungual onychomycosis