Uncovering subtle nail involvement in lichen planus with dermoscopy: a prospective, controlled study

Introduction
There are very few studies investigating the dermoscopic aspect of nail involvement in lichen planus and these studies described dermoscopic features of only clinically visible nail involvement in lichen planus.

Aim
To reveal subtle dermoscopic nail findings in patients with lichen planus.

Material and methods
The study included 40 patients with lichen planus and 40 healthy volunteers. All fingernails of the patients and healthy volunteers were examined by a handheld dermoscope and the findings detected were recorded. The patients were grouped by age, gender, disease duration and extent of the disease. The statistical analysis was performed using Chi square test.

Results
82.5% of the patients and 17.5% of the healthy volunteers showed at least one dermoscopic nail finding. The frequency of multiple splinter haemorrhage (p < 0.05), multiple leukonychia (p < 0.05), longitudinal erythronychia (p < 0.05), prominent hyponychial vascular structures (p < 0.05) and onycholysis (p < 0.05) observed in the patients group was statistically significant. The other findings included distal short longitudinal lines, onychorrhexis, solitary splinter haemorrhage and solitary punctate leukonychia and showed no statistically significant differences between the two groups.

Conclusions
To the best of our knowledge, this is the first study focusing on uncovering subtle nail involvement in lichen planus. The presence of dilated hyponychial vascular structures in lichen planus was first described in the present study. It can be concluded that the frequency of nail involvement in lichen planus is more than known. Dermoscopic imaging of the nails of all patients with lichen planus may help establish early diagnosis and treatment to avoid permanent nail damage.