31例羊水染色体异常核型、B超检查和产后随访分析

The analysis of 31 abnormal karyotypes of amniotic fluid

目的 总结 31例异常羊水细胞染色体的核型、B超检查和产后随访情况 ,为今后产前诊断提供经验。方法 原位法培养羊水细胞并制备染色体 ,G显带分析核型 ;B超检查胎儿 ;用一般体格检查法进行产后随访。结果 31例中 2 1三体征 6例 ,1 8三体征 1例 ,部分 1 8三体征 1例 ,部分 1 1三体征 1例 ,易位 1 0例 ,倒位 8例 ,嵌合体 4例。在孕中期 ,B超发现 2 1三体征 2例、1 8三体征发育迟缓 2例、嵌合体核型 1例 ,此嵌合体核型胎儿外生殖器模糊。产后随访发现 1例嵌合体核型的胎儿外生殖器畸形 ,与B超诊断相符 ;1例嵌合体核型的胎儿为多发畸形 ,B超未能发现。 2例嵌合体核型的胎儿未见异常。结论 B超可做为检查胎儿染色体异常的辅助诊断。羊水细胞培养、制备染色体诊断嵌合体须慎重 ,且重复检查羊水染色体对确诊意义不大。

Objective For better prenatal diagnosis, we retrospectively analyzed abnormal karyotypes of amniotic fluid cell,B ultrasonography and follow up of 31 cases.Methods Amniotic fluid cells were cultured in situ and their karyotypes were analyzed by G band.During second trimester,we also examined the fetus by B ultrasonography and followed them after delivery.Results In the 31 abnormal karyotypes,we found 6 cases of 21 trisomy,1 case of 18 trisomy,1 case of part 18 trisomy,1 case of part 11 trisomy,10 case of translocation,8 cases of inversion and 4 cases of mosaicism;B ultrasonography found 2 cases of 21 trisomy and 2 cases of 18 trisomy with IUGR,and the fetus of 46,XX/46,XY with ambiguous external genitalia.After the 4 fetus with the karyotypes of mosaicism were labored,one baby had abnormal external genitalia which was consistent with the B ultrasonography finding and one with multiple abnormalities while two babies were normal.Conclusions B ultrasonography can be used in the diagnosis of fetus with abnormal karyotype.The mosaicism from amniotic fluid cell cultures is difficult to interpretate.We should be cautious in prenatal diagnosis and the repeate amniotic fluid cell cultures is unnecessary.Follow up may be postponed until puberty.