联合NT与NIPT对胎儿染色体非整倍体筛查的应用研究

Application of combination of NT and NIPT in screening fetal chromosomal aneuploidy

目的通过对近两年在我院产检的NT阳性孕妇病例的NIPT结果分析,探讨联合两者用于胎儿染色体非整倍体筛查的临床价值。方法收集近两年(2015.5.1-2017.4.30)在我院产检门诊孕11~13+6w进行NT检查的孕妇病例资料,对其中接受侵入性产前诊断的105例筛查阳性者(NT检查≥2.5mm的孕妇)数据进行回顾性分析,自愿接受NIPT筛查检测的有39例,通过随访G显带染色体核型分析结果与妊娠结局,验证NT与NIPT筛查结果。结果经核型分析验证:105例NT阳性病例中32例确诊为染色体非整倍体,阳性预测值为30.48%(32/105),另有13例核型正常病例随访为不良妊娠结果。同时自愿行NIPT的39例病例中检测出14例高风险患者,其中13例确诊为染色体非整倍体胎儿,1例假阳性,阳性预测值率为92.85%(13/14),25例低风险病例染色体核型均正常且随访正常。联合筛查的阳性预测值明显优于单独NT筛查。结论超声NT检查联合NIPT技术的筛查模式将能够提高胎儿染色体非整倍体的准确率,增加阴性病例的排除能力,使侵入性产前诊断更有针对性,防止染色体异常胎儿的出生。

Objective：To investigate the clinical value of combined use of the two methods in screening fetal chromosomal aneuploidy by analyzing the NIPT results of NT positive pregnant women in the Maternal and Child Healthcare Hospital of Foshan during the past two years. Methods：The collection of the past two years（2015.5.1-2017.4.30）were examined by NT in our hospital outpatient antenatal examination of 11 - 13^＋6 gestational weeks pregnant cases,of which received invasive prenatal diagnosis of 105 cases of screening positive（NT≥2.5 mm pregnant women）data were retrospectively analyzed,the voluntary acceptance of NIPT screening detection in 39 cases through the follow-up of G banding karyotype analysis results and pregnancy outcomes,verification of the NT and NIPT screening results. Results：Karyotype analysis showed that in 105 cases of NT positive cases,32 cases were diagnosed as chromosomal aneuploidy,the positive predictive value was 30.48%（32/105）,and 13 cases of normal karyotype were followed up for adverse pregnancy outcomes. 14 cases of high risk patients were detected in 39 cases and voluntary NIPT,of which 13 cases were diagnosed as aneuploid fetuses,1 false positive,the positive predictive value was 92.85%（13/14）,25 cases of low risk cases had normal karyotype and normal follow-up. The positive predictive value of combined screening was significantly better than that of single NT screening. Conclusion：The screening mode of ultrasound NT combined with NIPT technology can improve the detection rate of fetal chromosomal aneuploidy,increase the exclusion ability of negative cases,make invasive prenatal diagnosis more targeted,and prevent the birth of chromosomal abnormalities.