ABSTRACT
Abstract Thyroid hormone has effects on the skin. Patients with hypothyroidism have changes such as dry, scaly and rough skin. Increase carotene in the dermis becomes a yellowish tone to the skin of the patient with hypothyroidism. There is an increase in capillary cycle (anagen phase) and nail growth and a reduction in eccrine gland secretion. It is a case of primary hypothyroidism with nail manifestations associated with dermatologic disorders and successful treatment with levothyroxine. Receptors for thyroid hormone have already been found in keratinocytes, fibroblasts, hair follicles and sebaceous glands. Genes responsive to thyroid hormones and elements of the hypothalamic-pituitary-thyroid axis were identified on the skin. This report highlights the importance of cutaneous manifestations as markers of thyroid disease.