Centre Hospitalier Universitaire Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Université Paris Descartes, and Société Française pour l'Amélioration des Pratiques Echographiques, Paris, France.
Am J Obstet Gynecol. 2013 Sep;209(3):223.e1-5. doi: 10.1016/j.ajog.2013.05.024. Epub 2013 May 11.
Screening at 11-13 weeks with ultrasound biparietal diameter (BPD) can detect half of open spina bifida cases. Maternal serum α-fetoprotein (AFP) levels at 15-19 weeks are increased 3- to 4-fold, in open spina bifida. We assessed whether combined screening using BPD, AFP, and other serum markers at 11-13 weeks would increase detection.
Maternal AFP levels were measured on serum stored at 11-13 weeks in 44 open spina bifida and 182 unaffected pregnancies, and results were expressed in multiples of the median (MoM) for gestational age. All samples had been measured for free β-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein (PAPP)-A. A multivariate Gaussian model was used to predict screening performance from the serum data and BPD measurements on 80 cases, including 36 previously published.
The median AFP level in cases was 1.201 MoM, significantly higher than in unaffected pregnancies (P < .01, 1 tail). The median free β-hCG was significantly reduced to 0.820 MoM (P < .02), but the median PAPP-A was similar in cases and controls. Modeling predicted the following: BPD alone would detect 50% of cases for a 5% false-positive rate or 63% for 10%; adding AFP increases detection by 2%; and a combined test with BPD, AFP, and free β-hCG detects 58% for 5% or 70% for 10%.
Combining AFP and BPD with free β-hCG as part of first-trimester aneuploidy screening would also allow early detection about two-thirds of cases with open spina bifida.
通过 11-13 周的超声双项径（BPD）筛查，可以检测到一半的开放性脊柱裂病例。在开放性脊柱裂中，15-19 周时的母体血清甲胎蛋白（AFP）水平增加 3-4 倍。我们评估了在 11-13 周时使用 BPD、AFP 和其他血清标志物进行联合筛查是否会提高检测率。
在 44 例开放性脊柱裂和 182 例无影响妊娠的 11-13 周储存的血清中测量了母体 AFP 水平，并根据妊娠年龄的中位数倍数（MoM）表示结果。所有样本均已测量游离β-人绒毛膜促性腺激素（β-hCG）和妊娠相关血浆蛋白（PAPP）-A。使用多元高斯模型从 80 例包括 36 例已发表病例的血清数据和 BPD 测量值中预测筛查性能。
病例的中位数 AFP 水平为 1.201 MoM，显著高于无影响妊娠（P <.01，1 尾）。游离β-hCG 的中位数显著降低至 0.820 MoM（P <.02），但病例和对照组的 PAPP-A 中位数相似。建模预测如下：BPD 单独检测 50%的病例，假阳性率为 5%或 63%，假阳性率为 10%；添加 AFP 可提高检测率 2%；BPD、AFP 和游离β-hCG 的联合检测可在 5%假阳性率时检测到 58%的病例，或在 10%假阳性率时检测到 70%的病例。
将 AFP 和 BPD 与游离β-hCG 相结合，作为第一 trimester 非整倍体筛查的一部分，也可以早期检测到大约三分之二的开放性脊柱裂病例。
