Non-epidermolytic palmoplantar keratoderma (Orphanet_2337, an Orphanet rare-disease nomenclature id) is a palmoplantar keratosis characterized by a well-demarcated, symmetric keratoderma located_in palms and located_in soles. Also known as: Autosomal dominant diffuse palmoplantar keratoderma, Norrbotten type, NEPPK, Thost-Unna Syndrome, Unna-Thost Syndrome, diffuse nonepidermolytic palmomplantar keratoderma, tylosis.