Nail lichen planus: A review of clinical presentation, diagnosis and therapy.

Lichen planus is a multifaceted disease of complex etiopathogenesis. Nails are involved in up to 10% of patients with lichen planus. Although most cases are mild, serious consequences may occur due to rapid progression of the disease, the high risk of scarring, and the resulting irreversible damage to the nail structure. Permanent damage of at least one nail occurs in approximately 4-12% of patients with nail lichen planus. In this narrative review, we emphasize the pathophysiology of nail lichen planus, the emergent nature of the disease, and the spectrum of different clinical manifestations. Diagnosis of nail disease in general, and of nail lichen planus in particular, is rapidly evolving. This review provides a comprehensive account of the non-invasive and invasive diagnostic techniques and treatment options reported in the literature, with emphasis on the efficacy and safety of the drugs used, the associated evidence, and the factors to be taken into account in planning and providing adequate treatment. The role of aesthetic and camouflage options is also summarized.