Trachyonychia: a comprehensive review.

Trachyonychia or rough nails, may present as an idiopathic disorder of the nails or it can be associated with other dermatological conditions. The dystrophic nail findings seen in trachyonychia are characterized by brittle, thin nails, with excessive longitudinal ridging. The most common histopathologic features associated with trachyonychia are spongiosis and exocytosis of inflammatory cells into the nail epithelia; typical features of lichen planus or psoriasis can also be detected. Determining the cause of trachyonychia is challenging. Treatment is often unsatisfactory, although in general it should be aimed at the underlying cause, if found. In most cases, the nail abnormalities improve spontaneously.