Sulzberg-Harde disease (other names: follicular hyperkeratosis, gerontological thyroiditis, Kelly - Whorton disease (eng. Kelly - Whorton disease; synonyms: Kelly-Wharton syndrome, Geriatric Goiter)) is a genetically determined chronic non-infectious disease of the skin and thyroid gland, which manifests itself keratinization of the skin of the legs and feet, dysfunction of the thyroid gland and a high risk of cancer. It is diagnosed mainly in elderly people. To date, the exact causes of development and treatment of the disease have not been established.