Clinical Application Of Ultrasound Combined With Noninvasive Prenatal Testing In Screening Fetal Chromosomal Aneuploidy

Objective:To analyze the clinical applicability and health economics of non-invasive prenatal testing(NIPT),and to explore the value of ultrasound combined with NIPT in screening Chromosome aneuploidy disease.Methods:3050 pregnant women who underwent NIPT in the second Hospital of Hebei Medical University from February 2018 to February 2020 were studied.The clinical applicability of NIPT was investigated by evaluating the screening efficacy of NIPT,following up the low-risk population after delivery,and analyzing the applicability of each group.Health economics was evaluated on the basis of literature review and field investigation.The ultrasound findings and NIPT results of cases with abnormal karyotype were analyzed to comprehensively evaluate the value of ultrasound combined with NIPT in screening Chromosome aneuploidy disease.Results:1.The specificity and sensitivity of NIPT for trisomy 13,18 and 21 were more than 98%,and the false positive rate and false negative rate were less than 16.7%.The specificity of NIPT for other autosomal aneuploidy and sex chromosome aneuploidy was 93.4% and 91.2% respectively.The sensitivity for sex chromosome aneuploidy was 60%.The false negative rate was 40%.2.Of the pregnancy outcomes in NIPT low-risk women,0.99% had a termination,1.27% had a spontaneous abortion,96.36% were born with good development,and 1.38% were born with abnormal development.3.NIPT screening was equally effective in the elderly and non-elderly groups.The specificity of serological screening was higher in the critical/high risk group than in the low risk group,but the sensitivity of the former was lower than that of the latter.The specificity and sensitivity of the group combined with abnormal ultrasonic soft index were higher than those of the group without abnormal ultrasonic soft index.4.The karyotype abnormality detection rates of single,two and more soft index abnormality were 7.5%,12.5% and 16.7%,respectively.5.Among the 18 patients diagnosed with T21,there are 50% not complicated with abnormal ultrasound soft marker,27.8% complicated with ventricular hypermyopia,27.8% complicated with nasal bone dysplasia or deletion,16.7% complicated with nuchal translucency thickness(NT)/ nuchal fold(NF)thickening,5.6% complicated with renal pelvis dilatation,and11.1% complicated with short femur.2 cases of T18 had choroid plexus cyst of lateral ventricle(100%).Among the 15 cases of SCA,there are 73.3% not complicated with abnormal ultrasound soft marker,13.3% complicated with ventricular hypertonic spot,6.7% complicated with NT/NF thickening and6.7% complicated with short femur.6.Among the 28 cases of abnormal karyotype in this study,there were 18 cases of trisomy 21,2 cases of trisomy 18,2 cases of 47,XXY,3 cases of47,XYY,and 3 cases of 45,X.7.Health economics analysis of NIPT: the cost-effectiveness ratios of serological screening strategy and NIPT screening strategy were 604554.67 yuan and 1394356.31 yuan,respectively.The safety indexes of serological screening strategy and NIPT screening strategy were 1.26,0.34 respectively.Conclusions:NIPT has good clinical applicability,but the cost of implementing NIPT comprehensive screening strategy is high,a more cost-effective NIPT screening model suitable for China should be further explored.Ultrasound and NIPT have their respective advantages,and the combined screening is beneficial to the detection of chromosomal aneuploidy diseases.