Oral pityriasis rubra pilaris.

Pityriasis rubra pilaris is a chronic, papulosquamous dermatosis of unknown etiology. Oral mucosal involvement of this condition is rare with only 3 previously reported cases in the English literature. A case of a 68-year-old man with pityriasis rubra pilaris with involvement of tongue and palate is presented. Clinical features, histopathologic features, and management of pityriasis rubra pilaris are discussed. We hereby present an additional case, the fourth worldwide, and review the literature.