Background  Nail lichen planus affects 10% of all patients with lichen planus. It is a severe disease that may lead to destruction of the nail plate. It affects fingernails more than toenails. Early diagnosis is important due to its aggressive behavior. Histopathology should be carried out, but in many occasions it is not enough to come to a conclusive diagnosis. Dermatoscopy, a complementary tool, has proven to be useful in its diagnosis, management, and prognosis. Currently, there is very little data regarding dermatoscopy of nail lichen planus.

Methods  Dermatoscopic photographic data of 11 patients having 79 nails affected with nail lichen planus, seen in a specialized nail disease facility, were selected and analyzed. The data was confirmed with histopathological analysis.

Results  Dermatoscopy showed abnormalities of the nail matrix, with trachyonychia in 40.51% and pitting in 34.18%. As to nail bed anomalies, there was chromonychia in 55.70%, fragmentation of body of nail in 50.63%, splinter hemorrhage in 35.44%, onycholysis in 27.85%, and subungual keratosis in 7.59%. Concerning anomalies that involved nail matrix, bed, and perionychial region altogether, there were longitudinal streaks in 82.28% and anonychia in 1.27%. Paronychia was present in 31.65% of the cases.

Conclusion  Considering that nail lichen planus is an underdiagnosed disease with severe consequences, early diagnosis is essential. This descriptive study of dermatoscopic characteristics of nail lichen planus would highlight some key changes in the course of the disease that will contribute to early diagnostic suspicion, early treatment, and could improve prognosis.