A family of RTH beta with p.R316C mutation presenting occasional syndrome of inappropriate secretion of TSH

作者：Ueda Yohei; Tagami Tetsuya^*; Tamanaha Tamiko; Kakita Maiko; Tanase Nakao Kanako; Nanba Kazutaka; Usui Takeshi; Naruse Mitsuhide; Shimatsu Akira

来源：Endocrine Journal, 2015, 62(3): 251-260.

DOI：10.1507/endocrj.ej14-0422

• SITSH
• RTH
• RTH beta
• TR beta
• p.R316C

The syndrome of inappropriate secretion of thyrotropin (SITSH) is a hallmark of resistance to thyroid hormone (RTH) due to mutations in the beta isoform of the thyroid hormone receptor (TR beta). Here, we report on a family of RTH due to a TR beta mutation (RTH beta) and presenting occasional SITSH. The proband was a 16 year-old girl with a goiter, detected at a school physical examination. She was initially diagnosed as having euthyroid Hashimoto thyroiditis because her thyroid function was normal with a positive anti-thyroglobulin antibody. Follow-up examinations resulted in mild SITSH on some occasions and euthyroid on the other occasions. A magnetic resonance imaging (MRI) revealed a normal pituitary gland. Because her mother also had mild SITSH, genetic analysis was performed and revealed a heterozygous point mutation in TR beta (p.R316C). Previously, the p.R316C had only been found in severe RTH cases with homozygous mutations or with an ectopic thyroid. Her mother with a heterozygous mutation showed variable RTH phenotype on T3 suppression testing. In conclusion, the prevalence of RTH beta might be underestimated and occasional SITSH could also suggest RTH beta. TR beta gene mutation is not always correlated with the RTH phenotype.

• 出版日期2015-3-20