孕早期胎儿NT联合血清游离β-hCG、AFP水平检测对唐氏综合征诊断价值分析

Diagnostic value of fetal NT combined with serum free β-hCG and AFP level for Down's syndrome in early pregnancy

目的分析B超测胎儿颈项透明层(NT)厚度联合血清游离人体绒膜促性腺激素(β-hCG)、甲胎蛋白(AFP)水平检测对孕早期胎儿唐氏综合征诊断价值。方法回顾性分析2014年7月至2016年12月丽水市中医院1 340例孕早期妇女临床资料,利用B超检测NT,然后进行母体血清AFP和游离β-hCG检测,并分析计算各组的唐氏综合征诊断灵敏度、特异度、假阳性率、假阴性率、阳性预测值、阴性预测值及约登指数。结果 NT筛查组为高风险的孕妇102例(7.61%),血清学二联检测筛查组为高风险的孕妇105例(7.84%),联合筛查组为高风险的孕妇40例(2.99%)。NT筛查组与血清学二联检测筛查组比较灵敏度、特异度、假阳性率、假阴性率、阳性预测值、阴性预测值均无显著性差异(χ2=0.035~0.467,均P>0.05),联合筛查组灵敏度、特异度、阳性预测值、阴性预测值均显著高于NT筛查组和血清学二联检测筛查组(χ2=20.210~49.585,均P<0.05),且假阳性率、假阴性率均显著低于NT筛查组和血清学二联检测筛查组(χ2=44.525~49.585,均P<0.05),联合筛查组约登指数最高,为0.99。结论 B超测NT联合血清游离β-hCG、AFP水平检测能提高孕早期胎儿唐氏综合征诊断灵敏度及阳性检出率。

Objective To analyze the value of fetal neck transparent （NT） combined with serum free human chorionic gonadotropin （β-hCG） and alpha fetoprotein （AFP） level in the diagnosis of Down＇s syndrome in early pregnancy. Methods The clinical data of 1 340 women of early pregnancy from July 2014 to December 2016 in Traditional Chinese Medicine Hospital of Lishui City were retrospectively analyzed. NT was detected by ultrasound, and then the maternal serum AFP and β-hCG were detected. Diagnostic sensitivity, specificity, false positive rate and false negative rate, positive predictive value, negative predictive value and Youden index among different groups were analyzed. Results There were 102 patients in the NT screening group with high risk （7.61%）, and 105 cases in the serological screening group （7.84 %） with high risk, and 40 cases in the combined screening group （2.99%） with high risk. Sensitivity, specificity, false positive rate, false negative rate, positive predictive value and negative predictive value were not significantly different among NT screening group and serological screening group （χ2 value ranged 0.035-0.035, all P〉 0.05）. Sensitivity, specificity, positive predictive value and negative predictive value were significantly higher in combined screening group than in NT screening group and serological screening group （χ2 value ranged 20.210-49.585, all P〈0.05）, but the false positive rate and false negative rate were significantly lower （χ2 value ranged 44.525 49.585, all P〈0.05）. The Youden index in combined screening group was highest, which was 0.99. Conclusion The detection of NT combined with serum β-HCG and AFP levels can improve the diagnostic sensitivity and positive rate of Down＇s syndrome in early pregnancy.