Maciel Léa Maria Zanini, Magalhães Patrícia Künzle Ribeiro
Division of Endocrinology, Department of Clinical Medicine, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, SP, Brazil.
Arq Bras Endocrinol Metabol. 2010 Nov;54(8):723-7. doi: 10.1590/s0004-27302010000800010.
We report the clinical and laboratory findings, and molecular analysis of a Brazilian patient with resistance to thyroid hormone syndrome (RTH) detected by neonatal screening. The index case was born at term by normal delivery with 2,920 g and 45 cm. TSH of the neonatal screening test performed on the 5(th) day of life was of 13.1 µU/mL (cut-off = 10 µU/mL). In a confirmatory test, serum TSH level was 4.3 µU/mL, total T4 was 19 µg/dL (confirmed in another sample, Total T4 = > 24.0 µg/dL), free T4 was 3.7 ηg/dL, and free T3 was 6.7 pg/mL. Direct sequencing of the beta thyroid hormone receptor gene revealed mutation c.1357C>A (P453T), confirming the diagnosis of RHT. Family study demonstrated the presence of RTH in his 1-year-and-3-month-old sister, in his 35-year-old father, and in his 68-year-old paternal grandfather. All of them had goiter and only his father had received an erroneous diagnosis of hyperthyroidism. The present case shows that clinical evaluation and a judicious interpretation of total T4/free T4 concentrations in a newborn recalled due to slightly altered neonatal TSH can contribute to the diagnosis of RTH.
我们报告了一名通过新生儿筛查检测出患有甲状腺激素抵抗综合征（RTH）的巴西患者的临床和实验室检查结果以及分子分析情况。该索引病例足月顺产，出生体重2920克，身长45厘米。出生后第5天进行的新生儿筛查试验中促甲状腺激素（TSH）为13.1微国际单位/毫升（临界值 = 10微国际单位/毫升）。在确诊试验中，血清TSH水平为4.3微国际单位/毫升，总甲状腺素（T4）为19微克/分升（在另一份样本中得到确认，总T4 => 24.0微克/分升），游离T4为3.7纳克/分升，游离三碘甲状腺原氨酸（T3）为6.7皮克/毫升。甲状腺激素β受体基因直接测序显示存在c.1357C>A（P453T）突变，从而确诊为RHT。家族研究表明，他1岁3个月大的妹妹、35岁的父亲和68岁的祖父均患有RTH。他们都有甲状腺肿大，只有他的父亲曾被误诊为甲状腺功能亢进。本病例表明，对于因新生儿TSH略有变化而被召回的新生儿，进行临床评估并明智地解读总T4/游离T4浓度有助于RTH的诊断。
