A rare chronic papulosquamous disorder of unknown etiology characterized by small follicular papules, scaly red-orange patches, and palmoplantar hyperkeratosis, which may progress to plaques or erythroderma. Although most of the cases are sporadic and acquired, a familial form of the disease exists. The disease is familial pityriasis rubra pilaris (MONDO_0008251). Also known as: Devergie's disease, PRP, hereditary pityriasis rubra pilaris, pityriasis rubra pilaris--familial type.