唐氏综合征孕中期多指标联合筛查方案适用性评估

Evaluation of Down＇s syndrome screening methods using maternal serum biochemistry in the second trimester pregnancy

目的对孕中期多种产前筛查方案进行比较、评价，为选择较为适宜的方案提供依据。方法收集2009年在青岛市产前诊断中心知情同意接受产前筛查的单活胎妊娠30547例，分别检测母血清中二联或三联血清标记物，均用Lifecycle软件评估胎儿罹患唐氏综合征的风险，对二者的检出率和成本效益进行比较、分析；同时收集64例唐氏综合征妊娠的血清标本，采用二联筛查（doubletest，DT）＋2T—Risks软件计算风险（DT-2T），二联筛查＋Lifecycle软件计算风险（DT—LC），三联筛查（tripletest，TT）＋2T—Risks软件计算风险（TT-2T）和三联筛查＋Lifecycle软件计算风险（TT—LC）4种不同的筛查方案对胎儿罹患唐氏综合征的风险进行评估，并对各种不同的筛查方案进行比较、评价。结果（1）64例唐氏综合征妊娠的血清标本，采用Lifecycle软件进行风险评估，检出率均高于同样指标筛查而采用2T-Risks软件评估风险方案；三联筛查不适宜使用2T—Risks软件；（2）30547例单活胎妊娠的筛查中，DT—LC方案和TT-LC方案对于唐氏综合征的检出率分别为56．25％和57．14％；每检出l例唐氏综合征的平均费用DT—LC方案明显低于TT—LC方案，为优选方案。结论孕中期DT—LC方案是一种利于在全国广泛开展的、经济有效的筛查方案。

Objective To provide basis for selecting the suitable method of Down＇s syndrome biochemical screening in the second trimester pregnancy. Methods A total of 30 547 singleton pregnancies between 14 and 20＋6 weeks of pregnancy were collected and analyzed for maternal serum alpha-fetoproteins （AFP） and human chorionic gonadotrophin, free beta subunit （13-HCG） with or without unconjugated estriol （uE3）. The screening risks were calculated using the software Lifecycle. The detection rates and the cost of per Down＇s syndrome detected were calculated and compared. And four different methods were compared in a series of 64 serum samples from Down＇ s syndrome pregnancies. Results （1） Among the 64 affected cases, the detection rate of Down＇s syndrome was improved no matter in the double test （DT） or in the triple test （TT） if software Lifecycle （LC） was used to evaluate risks. And it was not suitable to evaluate risks with software 2T-Risks in the triple tests. （2） In the cohort of 30 547 singleton pregnancies, the detection rate of Down＇s syndrome with project DT-LC, which was double test using AFP and free 13-HCG together with software Lifecycle, and project TT-LC, which was triple test using AFP, free 13-HCG and uE3 together with software Lifecycle, was 56. 25% and 57. 14M, respectively. The former project was better because it decreased the false positive rate at a lower running cost. Conclusion The DT-LC is an effective screening strategy for second trimester detection of fetal Down＇s syndrome in China's Mainland.