尼曼-匹克病B型的产前诊断

目的对尼曼－匹克病Ｂ型进行产前诊断。方法应用成色底物２－己癸酰氨基－４－硝基苯磷酸胆碱，对４例尼曼－匹克病Ｂ型先证者及其父母进行了外周血白细胞中鞘磷脂酶的酶学分析，并对这４例先证者再妊娠的母亲进行了绒毛、羊水细胞中的酶学分析。结果先证者均有明显的鞘磷脂酶的缺乏，而父母的酶水平与正常有重叠。对２例先证者母亲孕早期绒毛、孕中期羊水进行酶学分析，结果与正常个体差异均无显著意义，另外２例仅于孕中期作了羊水细胞中的酶学分析，结果亦正常。随访４名先证者母亲所生新生儿表型正常。结论绒毛和羊水细胞中鞘磷脂酶分析可用于尼曼－匹克病的产前诊断。

Prenatal diagnosis of type B Niemann Pick disease

Objective To evaluate an enzymatic method for postnatal and prenatal diagnosis of type B Niemann Pick disease (NPD).Methods Colorimetric substrate 2 hexadecanoylamino 4 nitrophenylphosphocholine (HNP) was used to measure acid sphingomyelinase (ASM) in peripheral leukocytes from 4 cases of type B NPD and their parents. The method was also used for chorionic villus samples and cultured amniocytes for prenatal diagnosis. Results The activity of ASM in leukocytes of probands was all markedly deficient, but the activity of ASM of the parents had an overlap between the normal range. Prenatal diagnosis in 4 pregnancies at risk of type B NPD showed that 2 cases were diagnosed in the first trimester by using chorionic villus samples and also in the second trimester by cultured amniocytes and the ASM activities were within the nomal range. Another 2 cases were diagnosed only in the second trimester by cultured amniocytes and the results were also normal. All infants developed normally after birth. Conclusion The measurement of ASM in chorionic villus samples and cultured amniocytes may provide a reliable approach to prenatal diagnosis of NPD.