早产儿暂时性低甲状腺素血症

早产儿暂时性低甲状腺素血症

曹　云

复旦大学附属儿科医院新生儿科 (上海 201102)

摘要：　随着新生儿重症监护救治技术的进展，极低出生体质量早产儿存活率明显提高。由于这些早产儿各器官系统结构和生理功能未成熟，新生儿期发病率高，而疾病可进一步影响早产儿的神经发育。甲状腺素在脑发育中具有重要

作用，而在早产儿脑发育关键期如发生甲状腺功能紊乱则可对其脑发育产生深远影响。暂时性低甲状腺素血症 (THOP) 是

早产儿最常见的甲状腺功能障碍，与极低出生体质量早产儿不良神经发育结局有关，补充甲状腺素可改善极低出生体质量

早产儿发生THOP后的神经发育预后。但目前对早产儿正常神经发育所需的适宜的血清甲状腺素水平尚未明确，因而需要

更进一步的随机对照研究为临床提供可靠的证据。 [临床儿科杂志，2013,31(3)：201-204]关键词：　低甲状腺素血症；　神经发育；　早产儿

中图分类号：　R722 文献标志码：　A 文章编号：　1000-3606(2013)03-0201-04

Transient hypothyroxinemia in preterm infant CAO Yun (Neonatal Department, Children’s Hospital of Fudan University, Shanghai 201102, China)

Abstract: With the advances in the care of premature infants in neonatal intensive care unit (NICU), the survival of very low birth weight premature infants increased significantly. These infants are characterized by a variety of organ and physiological systems immaturities predisposing to a high prevalence of neonatal morbidities. These morbidities have a major impact on neurodevelopment. Thyroid hormones are required for normal development of the human brain.

Derangements of critical thyroid function during the sensitive window in prematurity when early development occurs may have a range of long-term effects on brain development. Transient hypothyroxinemia of prematurity (THOP) is the most common thyroid dysfunction in premature infants. Several studies have demonstrated a correlation of THOP with poor neurodevelopment outcome in very low birth weight premature infants. There is suggestive evidence that thyroid hormone supplementation in very low birth weight infants with THOP can improve mental outcome. However, appropriate serum levels of thyroid hormones to achieve optimal brain maturation have not been quantified. Further prospective placebo controlled randomized clinical trial will provide sufficient evidence for clinical practice.

(J Clin Pediatr,2013,31(3):201-204) Key words: hypothyroxinemia; neurodevelopment; premature infant

doi:10.3969j.issn.1000-3606.2013.03.001·专家笔谈·

随着围生医学和新生儿危重症救治技术的进展，极低出生体质量 (very low birth weight，VLBW) 和超低出生体质量 (extremely low birth weight，ELBW) 早产儿的成活率明显提高。但对存活早产儿进行随访的研究结果显示，VLBW和ELBW早产儿神经发育损害 (脑瘫、智力低下、视觉和听觉障碍等) 发生率较足月儿明显升高，这些早产儿存活后的远期预后是目前关注的重点[1]。甲状腺素对神经系统发育具有重要作用。采用目前新生儿疾病筛查方法进行检测和评价发现，VLBW和ELBW早产儿，生后甲状腺素水平较足月儿低。临床研究发现，暂时性低甲状腺素血症 (transient hypothyroxinemia of prematurity，THOP) 是早产儿最常见的甲状腺功能障碍，其意义及对早产儿预后的影响尚未完全明确。

1　胎儿期甲状腺功能

约孕10周，胎儿下丘脑开始合成促甲状腺素释放激素(TRH)；孕12周，胎儿甲状腺开始合成甲状腺素 (T4)、三碘甲状腺原氨酸 (T3)、促甲状腺素 (TSH)。但孕早中期胎儿自身合成激素水平很低，主要依靠母亲经胎盘转运。孕早中期以及孕中期结束 (约为孕23~28周) 到出生后2~3岁是大脑迅速发育的2个重要时期，甲状腺素在

万方数据