Gentile F, Aloj S M
Centro di Endocrinologia e Oncologia Sperimentale, Consiglio Nazionale delle Ricerche, Università degli Studi Federico II, Naples, Italy.
Ann Ist Super Sanita. 1994;30(3):299-308.
Congenital hypothyroidism is a frequently occurring condition with possibly severe and irreversible consequences. Most of the cases are due to thyroid ectopia, aplasia or hypoplasia and are sporadic in occurrence. Inherited defects of thyroid hormone biosynthesis, secretion and utilization represent a minor, although not insignificant, fraction of the cases of congenital hypothyroidism. In a number of cases, transient congenital hypothyroidism can be due to such causes as maternal exposure to antithyroid drugs or excess iodine, transplacental transfer of blocking antibodies or endemic iodine deficiency. The latter is still a matter of concern in selected geographical areas. Both sporadic and familial cases of hypothalamic-pituitary hypothyroidism are quite rare. Early diagnosis of congenital hypothyroidism by mass screening programs is of the foremost importance for the prevention of long-term sequelae. The molecular defect has been elucidated in a number of inherited defects of thyroid hormone biosynthesis, secretion and utilization. These include impaired thyroidal response to thyroid-stimulating hormone (TSH) due to an altered TSH receptor, defective synthesis of thyroglobulin, defective synthesis of thyroid peroxidase, generalized resistance to thyroid hormone, and familial isolated TSH deficiency. It is anticipated that, as more mutations become available for detailed molecular analysis, further advances in our knowledge of the molecular aspects of thyroid function will ensue in the near future.
先天性甲状腺功能减退症是一种常见疾病，可能会导致严重且不可逆的后果。大多数病例是由于甲状腺异位、发育不全或发育不良引起的，且为散发性。甲状腺激素生物合成、分泌和利用的遗传性缺陷在先天性甲状腺功能减退症病例中占比虽小，但并非微不足道。在许多情况下，暂时性先天性甲状腺功能减退症可能是由母亲接触抗甲状腺药物或碘过量、阻断抗体的胎盘转运或地方性碘缺乏等原因引起的。在某些特定地理区域，后者仍是一个令人担忧的问题。散发性和家族性下丘脑 - 垂体性甲状腺功能减退症都相当罕见。通过大规模筛查计划对先天性甲状腺功能减退症进行早期诊断对于预防长期后遗症至关重要。在甲状腺激素生物合成、分泌和利用的一些遗传性缺陷中，分子缺陷已得到阐明。这些包括由于促甲状腺激素（TSH）受体改变导致甲状腺对TSH反应受损、甲状腺球蛋白合成缺陷、甲状腺过氧化物酶合成缺陷、全身性甲状腺激素抵抗以及家族性孤立性TSH缺乏。预计随着更多突变可用于详细的分子分析，在不久的将来，我们对甲状腺功能分子方面的认识将取得进一步进展。
