METHODS: We encountered a primiparous singleton pregnant woman with a rare CPM consisting of 47,XY,+21; 47,XXY; and 46,XY, who obtained a false-positive result on NIPT with a high risk for trisomy 21. Copy-number variation sequencing on amniotic fluid cells, fetal tissue, and placental biopsies showed that the fetal karyotype was 47,XXY, while the placenta was a rare mosaic of 47,XY,+21; 47,XXY; and 46,XY.
CONCLUSIONS: The patient had a rare CPM consisting of 47,XY,+21; 47,XXY; and 46,XY, which caused a discrepancy between the result of NIPT and the actual fetal karyotype. It is important to remember that NIPT is a screening test, not a diagnostic test. Any positive result should be confirmed with invasive testing, and routine ultrasound examination is still necessary after a negative result.
方法:我们遇到了一位初产的单胎孕妇,患有罕见的CPM,包括47,XY,+21;47,XXY;和46,XY,谁在NIPT上获得了假阳性结果,具有21三体的高风险。羊水细胞的拷贝数变异测序,胎儿组织,胎盘活检显示胎儿核型为47,XXY,而胎盘是一个罕见的马赛克47,XY,+21;47,XXY;和46,XY。
结论:患者有一个罕见的CPM,包括47,XY,+21;47,XXY;和46,XY,这导致了NIPT结果与实际胎儿核型之间的差异。重要的是要记住,NIPT是一种筛查测试,不是诊断测试。任何阳性结果都应该通过侵入性测试来确认,结果阴性后仍需常规超声检查。