A CLINICAL ONYCHOSCOPIC ANALYSIS IN THE DIAGNOSIS OF PRIMARY ONYCHOMYCOSIS

Background: Onychomycosis is one of the commonest fungal infections affecting the nails. Laboratory investigations for onychomycosis   are often time-consuming, so there is a need for a quick and reliable modality to establish a definitive diagnosis. Dermoscopy is a non- invasive, rapid and effective method of investigation in dermatology. In this study, we have analyzed various patterns of onychoscopy among the clinical subtypes of onychomycosis.

Methodology: This cross-sectional observational study included 132 patients attending the dermatology Outpatient Department (OPD) who were clinically diagnosed with onychomycosis. Of these, 101 patients with KOH-positive fingernail samples, underwent onychoscopic examination using a DermLite DL4E4767 with X10 magnification. Various dermoscopic patterns of the affected nails were recorded and analysed.

Results: Among the 101 patients, Distal subungual onychomycosis (DLSO) was the most common subtype (75.2%), followed by Total dystrophic onychomycosis (TDO) (31.7%), Paronychia (27.72%), Proximal subungual onychomycosis (PSO) (6.9%) and Superficial White onychomycosis (SWO)5%. No cases of the endonyx type were observed. The most frequent dermoscopic features included: Ruin pattern (68.31%), superficial transverse striations (42.57%), chromonychia (40.59%), jagged spikes (31.6%), longitudinal ridges (22.7%), Subungual hyperkeratosis (15.84%), Aurora borealis (10.8%), Splinter haemorrhage (3%), and Leukonychia (3%).

Conclusion: We identified several dermoscopic features that were highly specific for onychomycosis. Onychoscopy, being a simple bedside procedure, should be considered an important diagnostic tool in suspected cases of onychomycosis, particularly when laboratory confirmation is delayed or unavailable.