Approach to the patients with resistance to thyroid hormone

Syndrome of resistance to thyroid hormone (RTH) is a rare disorder with reduced tissue response to thyroid hormones,and it is characterized by elevated circulating free thyroid hormones (FT3 and FT4) and nonsuppressed serum TSH.More than 90％ of RTH are hereditary,displaying autosomal dominant inheritance,most of which are linked to mutations of thyroid hormone receptor β gene (TRβ).RTH has a high degree of clinical heterogeneity,and the clinical manifestations are varied among patients with different course,among different families with RTH and even among different affected family members in one family.Because RTH can be easily confused with the other common thyroid diseases,misdiagnosis and mistherapy are often encountered in RTH patients due to lack of understanding of RTH.Here we present a case of RTH with genetic diagnosis and treatment together with the TRβ gene screening results in her mother in order to call attention to the diagnosis and treatment of RTH. Key words: Syndrome of resistance to thyroid hormone;  TRH-stimulation test ;  Octrotide-suppression test ; TRβ gene