产前胎儿染色体异常筛查中无创产前基因检测的临床价值分析

The clinical value of noninvasive prenatal gene testing in prenatal screening of fetal chromosomal abnormality

目的分析无创产前基因检测(NIPT)在染色体筛查中的应用价值。方法回顾性收集2016年1月至2019年12月在我院进行产检的孕妇10343例,根据孕周、NIPT申请理由进行分组,并对入选孕妇进行随访,直至胎儿出生后1个月。分析不同孕期、不同申请理由中NIPT检出情况,并对比羊膜腔穿刺核型分析检查与NIPT结果。结果本组10343例孕妇中,NIPT提示136例(1.31%)胎儿染色体异常。其中孕早期、中期、晚期NIPT分别检出33、70、33例异常,检出率分别为1.57%、1.27%、1.22%;高龄、血清学筛查异常、B超软指标异常、主动申请组NIPT分别有49、41、17、19例异常,检出率分别为1.36%、1.39%、1.27%、0.78%;136例NIPT异常中,4例拒绝产前诊断确诊,132例行羊膜腔穿刺染色体检查,检出88例染色体非整倍体异常。其中NIPT检查阳性T21、T13、T18、性染色体异常、染色体微缺失微重复分别为29、5、13、80、5例,阳性预测值分别为:86.21%、20.00%、76.92%、58.75%、100.00%。结论产前胎儿染色体异常筛查中NIPT作为无创检查,对T21、T18、T13异常情况筛查效能佳,可作为产前筛查的重要手段,但对是否可作为染色体微缺失微重复辅助检查的手段有待进一步研究。

Objective To analyze the application value of noninvasive prenatal gene testing(NIPT)in chromosome screening.Methods From January 2016 to December 2019,10,343 pregnant women who underwent obstetrical examinations in our hospital were collected retrospectively.They were grouped according to the gestational weeks and reasons for NIPT application.The selected pregnant women were followed up until 1 month after the birth.The NIPT examinations in different periods of pregnancy and different application reasons were analyzed.The karyotype analysis of amniocentesis was compared with the result of NIPT.Results In the 10,343 pregnant women,NIPT showed 136 cases(1.31%)with fetal chromosomal abnormalities.Among them,33,70 and 33 cases with abnormalities were detected by NIPT in the first,second and third trimesters,respectively,and the detection rates were 1.57%,1.27%,and 1.22%,respectively.There were 49,41,17 and 19 cases with abnormalities in advanced age group,serological screening abnormality group,abnormal soft index of B ultrasound group,and active application of NIPT group.The detection rates were 1.36%,1.39%,1.27%and 0.78%,respectively.Among 136 cases with NIPT abnormalities,4 cases refused prenatal diagnosis,132 cases underwent amniocentesis chromosomal examination,and 88 cases with chromosomal aneuploidy abnormalities were detected.NIPT examination showed there were 29 cases with positive T21,5 cases with positive T13,13 cases with positive T18,80 cases with sex chromosome abnormalities,and 5 cases with microchromosomal microdeletions and microduplications.The positive predictive values were 86.21%,20.00%,76.92%,58.75%,and 100.00%respectively.Conclusion NIPT can be used as a non-invasive test in fetal chromosomal abnormality of prenatal screening.It has a good screening effect in screening T21,T18,and T13 abnormalities.It can be used as an important means of prenatal screening.However,whether it can be used as a method of auxiliary examination for chromosome microdeletions and microduplications needs further study.