Lichen planus limited to the nail is uncommon, and information about its long-term prognosis is lacking.

We attempted to review the epidemiological, clinical and histological features, the response to treatment and the follow-up of a large series of patients with nail lichen planus (NLP). We searched for the records of all patients with a clinical and histopathological diagnosis of isolated NLP apart from January 1997 to December 2008. The patients presented during this period and followed until December 2009 in the consultation for nail disorder were reviewed in detail. Data on 67 patients were collected, with an average age of 47 years (6-78 years). A male preponderance was observed (64%). The mean duration of the disease was about 38 months. Fingernails were the site of involvement in 94% of cases. Matrix involvement was observed in 91% of cases. A total of 120 specimen's biopsy were taken and was contributory in 90% of cases. Two specimens biopsy were practiced in 70.15% of patients. Systemic corticosteroids were used in 46 patients, and associated in 20 cases to intralesional corticosteroids. Our findings indicate that if NLP is correctly diagnosed and appropriately treated. Nail biopsy is proven to be a relatively simple, safe and useful procedure with a minimal scarring risk. Long-term observation indicates that the prognosis of NLP is poor with high rate of relapses, with permanent damage to the nail unit.

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