[Diagnosis and management of nail psoriasis].

Nail psoriasis has traditionally been considered as one of the most difficult forms of psoriasis to treat. The most recent studies have found a higher prevalence of fungal infections in psoriatic nails and therefore cultures before and during treatment are necessary. Over the last few years, novel psoriatic therapies have been developed, some of which are effective for both skin and nail lesions (cyclosporine and biologic agents). Of the topical agents, vitamin D and A derivatives as well as nail lacquer containing 8 % clobetasol propionate can help improve lesions of both the nail bed and matrix.