产前诊断中羊水细胞嵌合体的回顾性分析

目的通过对产前诊断中羊水细胞嵌合体发生率,真假嵌合体的鉴别以及不同类型嵌合体胎儿的妊娠结局的回顾性分析,从而对羊水细胞嵌合体病例的产前咨询和处理做一个更好的临床指引。方法收集2001年1月至2008年12月,因各种产前诊断指征来我院行羊膜腔穿刺术及产前染色体检查检出为嵌合体的病例共26例。统计嵌合体的检出率、检出类型、相应的脐血染色体分析结果。并对所有病例进行出生后随访。结果嵌合体发生率为0.89%。其中,性染色体XX/XY嵌合体5例(占19.23%);数目异常嵌合体9例(占34.62%);结构异常嵌合体12例(占46.15%)。经脐血染色体检查,确诊为真性嵌合体的仅2例,均终止妊娠;诊为假性嵌合体的16个病例中,除1例失访外,余均正常分娩,出生随访未见异常。未行进一步脐血检查的8个病例中,3例失访,3例终止妊娠,余2例均正常分娩,出生随访未见异常。结论产前诊断羊水细胞嵌合体多为假性嵌合体,各种类型的假嵌合体一般预后均良好。当发现羊水嵌合体时,首先应正确诊断真假嵌合体;并可根据嵌合体的类型进行预后评估。

To retrospective analysis the chromosome mosaicism of amniocyte in prenatal diagnosis.

Objective： To retrospective analysis the incidence of amniocyte mosaics in prenatal diagnosis, the difference of true mosaic and pseudo - mosaic, and the pregnancy outcome of the different types of mosaics, in order to give some better guidelines of prenatal consultation and management. Methods： During 2001 to 2008, there detected 26 cases of chromosome mosaiesm from prena- tal chromosomal diagnosis of amniocentesis. To study the incidence rate, types and the results of fetal blood chromosomal analysis. And follow up the pregnancy outcome of all cases. Results： The incidence rate of mosaics is 0. 89%. There are 5 cases of sex chro- mosome XX/XY abnormality （19.23%）, 9 cases of numerical abnormality （34. 62% ）, 12 eases of structural abnormality （46. 15% ）. By the help of chromosomal analysis in fetal blood, to identified 2 cases of true mosaics, and there were termination of pregnancy. All of pseudo - mosaic cases have a normal outcome except one case did not feed back. In the cases who did not perform the fetal blood chromosomal analysis, there are 3 cases of not feed back, 3 cases of termination of pregnancy, and 2 cases of good outcome. Conclusion ： Most amniocyte mosiacism are pseudo - mosaic, and all types of pseudo - mosaics have a good outcome in general. It＇s importance to distinguish the true or pseudo mosaics. And we can evaluate the prognosis according to the type of the chromosome mosaicism of amnioeyte.