Kennedy D, Chitayat D, Winsor E J, Silver M, Toi A
Prenatal Diagnosis Program, Toronto Hospital--General Division, Ontario, Canada.
Am J Med Genet. 1998 May 26;77(4):317-21. doi: 10.1002/(sici)1096-8628(19980526)77:4<317::aid-ajmg13>3.0.co;2-l.
From January 1990 until December 1996, 212 cases of neural tube defect (NTD) were seen through the Prenatal Diagnosis Program of the University of Toronto. Of the 212 cases, 200 were karyotyped successfully and of these, 13 (6.5%) had chromosome abnormalities. When classified according to the site of the NTD, 2.3% (2/88) of anencephalics, 7.1% (1/14) of encephaloceles, and 10.2% (10/98) of meningomyeloceles had abnormal karyotypes. The absence of associated ultrasound abnormalities was not necessarily predictive of a chromosomally normal fetus; 4/167 (2.4%) of fetuses with isolated NTDs had chromosome abnormalities. Conversely, 24/33 (72%) of fetuses with additional findings on ultrasound had normal chromosomes. The diagnosis of a chromosome abnormality associated with NTD has important implications for recurrence risk and prenatal diagnosis, not only for the parents but potentially for other relatives. Based on our finding that 6.5% of prenatally detected NTDs are associated with chromosome abnormalities, we recommend karyotyping of all fetuses and/or newborns with NTD.
从1990年1月至1996年12月，通过多伦多大学的产前诊断项目共诊治了212例神经管缺陷（NTD）病例。在这212例病例中，200例成功进行了核型分析，其中13例（6.5%）存在染色体异常。根据NTD的部位分类，无脑儿中有2.3%（2/88）、脑膨出中有7.1%（1/14）、脊髓脊膜膨出中有10.2%（10/98）存在核型异常。未伴有超声异常并不一定预示胎儿染色体正常；孤立性NTD胎儿中有4/167（2.4%）存在染色体异常。相反，超声检查有其他异常发现的胎儿中，24/33（72%）染色体正常。与NTD相关的染色体异常诊断对复发风险和产前诊断具有重要意义，不仅对父母，对其他亲属也可能如此。基于我们发现6.5%的产前检测到的NTD与染色体异常相关，我们建议对所有患有NTD的胎儿和/或新生儿进行核型分析。
