Sammanfattning
A 37-year-old female was examined for thyrotoxicosis. Laboratory findings showed elevated T4 and T3 and normal TSH. Antithyroid treatment was prescribed but due to a rise in TSH-levels the treatment was terminated. The mutation Pro453Thr in the TR-ß gene of the patient was identified. Resistance to thyroid hormone (RTH) is characterized by elevated levels of serum T4 and/or T3 in combination with normal or elevated levels of TSH. RTH is due to a mutation in the gene - TR-ß - coding for the ß -isoform of the thyroid hormone receptor.