Dermoscopic Features of Distal Lateral Subungual Onychomycosis

Background Onychomycosis is a very common disease and accounts for upto 50% of the diseases affecting the nail apparatus. Diagnosis of onychomycosis is usually confirmed with the help of a potassium hydroxide (KOH) mount and fungal culture. Onychoscopy can be a handy and additional tool for the diagnosis. Aims and Objectives To determine the dermoscopic findings in distal lateral subungual onychomycosis (DLSO). Materials and Methods A prospective study of 60 nails with a clinical and mycological diagnosis (KOH with Chicago sky blue positive) of DLSO. Dermoscopic examination was performed using a Heine delta 20 plus dermatoscope and the features were recorded. Results Longitudinal striae and jagged proximal edges seen in all 60 (100%) patients. Intermittent spiked pattern was seen in 47 nails (78.3%). Chromonychia and distal irregular termination were noticed in 23 (38.3%) and 7 (11.7%) nails, respectively. Conclusions Onychoscopy can be used as an important diagnostic tool while evaluating nail disease, especially in DLSO. Limitations Small study sample and lack of comparison with other nail diseases that manifests with distal onycholysis.