早产儿暂时性低甲状腺素血症与脑损伤及神经行为学相关性研究

目的 通过对早产儿甲状腺素水平测定及脑、神经行为发育测评,分析甲状腺素水平与脑损伤、神经行为学的相关性.方法 选取2009年11月至2010年4月,上海交通大学附属上海市儿童医院新生儿科收治的早产儿52例,生后6 h内留取血清样本,放射免疫法测定T3、T4、TSH值.所有患儿出生后3 d行头颅B超检查,每周复查1次,出院前行头颅MRI检查.根据头颅MRI结果将患儿分为3组:无脑损伤组(33例)、脑室内出血组(10例)、脑白质损伤组(9例).所有患儿于纠正胎龄40±2周时行新生儿20项行为神经测定.结果 3组患儿TSH均正常,排除先天性甲状腺功能减低症;共8例早产儿甲状腺功能正常,占15.4%(8/52);另44例早产儿甲状腺功能均低下,占84.6%(44/52).无脑损伤组T3、T4水平高于脑室内出血组及脑白质损伤组,并以脑白质损伤组T3、T4水平最为低下,3组间比较差异有统计学意义(P＜0.05).无脑损伤组患儿行为能力、被动肌张力、主动肌张力及总分4项得分显著高于有脑损伤的两组患儿,且脑室内出血组患儿得分又高于脑白质损伤组患儿,3组间比较差异有统计学意义(P＜0.05).结论 早产儿脑损伤越严重,甲状腺素水平越低.有脑损伤的早产儿神经行为学评分较无脑损伤的早产儿低.

Transient hypothyroxinemia, brain injury and neuroethology in preterm infants

Objective To analyse the associativity among serum thyroid hormone level,brain injury and neuroethology in preterm infants by testing the thyroid hormone level and neuro-behaviour assessment.Methods Fifty-two preterm infants were continuously admitted in neonatal department of Shanghai Children's Hospital from Dec 2009 to Apr 2010. Radio-immunity was used to determine the serum level of T3,T4, TSH within 6 h after birth. Each case received cranial ultrasonic examination within 3 d after birth and rechecked every week. Before discharge, every infant received a cranial MRI examination. The 52 cases were devided into three groups according to the result of ultrasound and MRI:no brain damage group (33 cases),intraventricular hemorrhage greup (10 cases) ,and white matter injury group (9 cases). At the corrected gestation age 40±2 weeks,every infant received a neonatal behavioral neurological assessment (NBNA). Results The level of serum TSH in all the three groups of preterm infants were normal, which could reject congenital hypothyroidism. Eight preterm infants(15.4% ,8/52) had normal thyroid hormone level,another 44 preterm infants(84. 6% ,44/52) got lower thyroid functions. The levels of T3 and T4 were higher in the no brain damage group than those in intraventricular hemorrhage group and white matter injury group. And the preterm infants who had white mauer injury got the lowest level of thyroine hormone T3 and T4. Thyroxine hormone levels had significant difference among three groups (P ＜ 0. 05). The preterm infants who had no brain damage got higher scores in capability, passive muscle tonus,initiative muscle tonus and total score than the other two groups. Intraventricular hemorrhage group always got higher scores in NBNA than the white matter injury group (P ＜ 0. 05). The NBNA scores had significant difference among three groups (P ＜ 0. 05). Conclusion Premature infant who has more severe brain injury always has lower levels of thyroxine hormone. Premature infants with brain injury get lower scores in NBNA test than those without brain injury.