67例颈后皮肤皱褶增厚胎儿产前诊断结果分析

 目的 探讨颈后皮肤皱褶厚度(nuchal fold, NF)增厚胎儿染色体异常的类型及分布,明确NF增厚的临床意义。方法 以≥14周胎儿NF≥6 mm为NF增厚诊断标准,回顾性分析2013-01至2016-12医院67例NF增厚胎儿的产前诊断临床资料,其中18~23⁺⁶周胎儿行羊膜腔穿刺,≥24周胎儿行超声引导下脐静脉穿刺,死胎在流产后取胎儿组织送检,分析胎儿标本的染色体核型及基因拷贝数变异结果。结果 67例NF增厚胎儿染色体异常发生率为13.4%(9/67),其中21-三体4例,18-三体2例,性染色体异常1例,病理性致病性基因拷贝数变异2例;孤立性NF增厚胎儿的染色体异常发病率为3%(1/33),显著低于综合征性NF增厚胎儿(23.5%,8/34)。结论 NF是胎儿染色体异常的重要指标,对于NF增厚的胎儿的产前诊断,除了常规检查核型以外,还需要重视检测基因拷贝数变异,特别是综合征性的NF增厚胎儿。

Chromosomal analysis of 67 cases of fetuses with thick nuchal fold

Objective To explore the applicability of chromosomal analysis of fetuses with thick nuchal fold.Methods The clinical data on sixty-seven pregnancies diagnosed as thick nuchal fold during prenatal diagnosis between January 2013 to December 2019 in Beijing Obstetrics and Gynecology Hospital was retrospectively analyzed,including amniotic fluid (between 18 to 23⁺⁶ weeks of gestation), umbilical blood sampling(after 24 weeks of gestation)or fetal tissue of stillbirth. The chromosomal karyotype of fetal samples and copy number variations(CNVs ) of genes were analyzed.Results 13.4%(9/67) of chromosome abnormities were diagnosed with thick nuchal fold, including four with trisomy 21, two with trisomy 18, one with X chromosome aneuploidy and two with pathogenic CNVs respectively. There was one case of chromosomal abnormalities in the thirty-three cases of fetuses with isolated thick nuchal fold. There were eight cases of chromosomal abnormalities in the thirty-four cases of fetuses with thick nuchal fold(8/34, 23.5%).Conclusions The incidence of chromosomal abnormalities in fetuses with thick nuchal fold is high and prenatal diagnosis is recommended for the patients. For fetuses with thick nuchal fold,prenatal diagnosis of CNVs is recommended,especially those with comprehensive NF thickening.