Klinefelter综合征在18318例羊水染色体产前诊断中的检出情况及临床特点

Detection result and clinical characteristics of Klinefelter′s syndrome in prenatal diagnosis of amniotic fluid chromosome:a report of 18318 cases

目的了解Klinefelter综合征在羊水染色体产前诊断中的检出情况及其临床特点。方法收集18318例行羊水染色体核型分析孕妇的检测结果及其产前筛查、产前诊断的结果,并追踪其妊娠结局。结果在18318例羊水产前诊断样本中检出Klinefelter综合征34例(检出率为1.86‰),其中47,XXY 30例、嵌合体型3例、48,XXYY 1例。34例Klinefelter综合征中,28例选择引产,6例继续妊娠;仅2例产前超声存在异常;15例接受无创产前检测(NIPT),均提示性染色体异常;25例采用分子诊断学多重连接探针扩增技术(MLPA)或基因组拷贝数变异测序的方法验证,其中24例与染色体核型分析一致。结论Klinefelter综合征在产前诊断中检出率不高,以典型的47,XXY为最常见的核型。部分Klinefelter综合征患者在胎儿期表现正常,而在出生后才表现异常的临床表征。NIPT或可作为Klinefelter综合征的产前筛查的有效手段,而染色体核型分析结合MLPA等分子诊断学技术可更准确地检出Klinefelter综合征。

Objective To understand the detection result and clinical characteristics of Klinefelter′s syndrome in prenatal diagnosis of amniotic fluid chromosome.Methods The detection results of amniotic fluid karyotype analysis as well as the results of prenatal screening and prenatal diagnosis were collected from 18318 pregnant women,and their pregnancy outcomes were followed up.Results Among 18318 amniotic fluid samples for prenatal diagnosis,Klinefelter′s syndrome were found in 34 cases with a detection rate of 1.86‰,including 47,XXY in 30 cases,chimerism in three cases,48,XXYY in one case.In the 34 cases of Klinefelter′s syndrome,28 cases received induced labor and six cases chose pregnancy;only two cases presented abnormal manifestation on prenatal ultrasound;totally 15 cases underwent non-invasive prenatal testing(NIPT)and were all diagnosed as abnormal sex chromosome;25 cases were validated by multiplex ligation-dependent probe amplification(MLPA)in molecular diagnostics or genetic copy number variation sequencing in the genome,and the results were consistent with those of karyotype analysis in 24 cases.Conclusion The detection rate of Klinefelter′s syndrome is not high in prenatal diagnosis,and the typical 47,XXY is the most common karyotype.Partial Klinefelter′s syndrome patients manifest normality in fetal stage,but manifest abnormal clinical phenotype after birth.NIPT may be used as an effective means of prenatal screening for Klinefelter′s syndrome,and karyotype analysis combined with molecular diagnostics such as MLPA can more accurately identify Klinefelter′s syndrome.