生殖医学杂志2023，Vol.32Issue(12)：1843-1848,6.DOI:10.3969/j.issn.1004-3845.2023.12.013
NIPT产前筛查染色体异常及高风险Z值分类的意义
The significance of NIPT prenatal screening for chromosomal abnormalities and high-risk Z-value classification
摘要
Abstract
Objective:To explore the application of non-invasive prenatal testing(NIPT)in detecting fetal chromosomal aneuploidy and the significance of high-risk Z-value classification. Methods:A total of 7 478 pregnant women who experienced NIPT at the Genetic Consultation Clinic of Wuhai Maternal and Child Health Hospital from June 2015 to January 2023 were recruited.The NIPT of fetal free DNA from maternal peripheral blood was conducted.The Z value was developed by a bioinformatics analysis and those of high-risk women were divided into four groups:Group A(3≤Z≤5),Group B(5＜Z≤8),Group C(8＜Z≤12)and Group D(Z＞12).The false positive rates were compared among four groups.Fluorescence in situ hybridization(FISH)detection of amniocentesis fluid and analysis of fetal chromosome karyotype were conducted among high-risk pregnant women. Results:A total of 62 chromosomal abnormalities were detected in 7 478 NIPT samples,with a positive rate of 0.83％,including 44 cases with high-risk for trisomy 21,12 cases with high-risk for trisomy 18 and 5 cases with high-risk for trisomy 13,and 1 chromosomal abnormality.Among them,54 pregnant women voluntarily underwent amniocentesis for prenatal diagnosis,and 50 of them underwent FISH technology and chromosomal karyotype analysis.Forty cases were confirmed in Wuhai Maternal and Child Health Hospital,in which 29 cases of trisomy 21,9 cases of trisomy 18,1 case of trisomy 13,and 1 case of trisomy X.Four cases underwent amniocentesis in other hospitals.Among them,3 cases of trisomy 21 and 1 normal case were found.Subsequent follow-up revealed that among 8 women without amniocentesis,5 women underwent induction of labor.Four cases were confirmed as trisomy 21 and 1 case as trisomy 13.A child suffered from trisomy 21 was born due to personal reasons.Intrauterine fetal death and a normal infant delivered by cesarean section at 34 gestational week were found in a case of twins.A women with high-risk of trisomy 18 ultimately delivered a normal baby.The positive predictive values(PPV)of NIPT for trisomy 21,trisomy 18,and trisomy 13 were 86.4％(38/44),75.0％(9/12),and 40.0％(2/5),respectively.Excluding one case of sex chromosome abnormality,the evaluation results of Z values of the remaining 61 high-risk cases showed that the false positive rates were 69.2％,14.3％,5.3％and 0 when the Z values were between 3 and 5,greater than 5 but not more than 8,greater than 8 and not more than 12,and greater than 12,respectively. Conclusions:There is a high screening accuracy for trisomy 21 and trisomy 18 by NIPT.Some diagnostic indicators such as sensitivity,specificity,positive predictive value,and negative predictive value should be used in NIPT for prenatal diagnosis of fetal chromosomal aneuploidy diseases.False positives appear mainly when the Z values are between 3 and 5,and the Z-value is negatively correlated with the false positive rate.Proper classification of high-risk Z values for NIPT can further improve the positive predictive results of trisomy 21,trisomy 1-8,and trisomy 13,and are beneficial to guiding clinical physicians in genetic counseling for high-risk pregnant women.关键词
无创产前检测/荧光原位杂交/羊水细胞培养/产前诊断/Z值Key words
Non-invasive prenatal testing/Fluorescence in situ hybridization/Amniotic fluid cell culture/Prenatal testing/Z value分类
医药卫生引用本文复制引用
郑海燕,武燕红,张欣,吴雪溶,吕伟,张海平,王震,沈静,高敏..NIPT产前筛查染色体异常及高风险Z值分类的意义[J].生殖医学杂志,2023,32(12):1843-1848,6.基金项目
内蒙古自治区科技创新引导奖励资金(2022765) （2022765）
