Spontaneous resolution of cystic hygroma in 47,XYY fetus

Current Perspectives of Prenatal Cell-free DNA Screening in Clinical Management of First-Trimester Septated Cystic Hygroma

First-trimester septated cystic hygroma occurs in approximately 1 in 268 pregnancies and has long been associated with a markedly increased risk of fetal aneuploidy and, among euploid fetuses, an increased risk of structural anomalies primarily affecting the cardiac and skeletal systems. Invasive prenatal diagnosis – chorionic villus sampling and/or amniocentesis – encompasses the time-honored clinical tools for the next step in management following prenatal sonographic diagnosis of first-trimester septated cystic hygroma. Currently, prenatal cell-free DNA (cfDNA) screening for fetal aneuploidy with select microdeletions is gradually replacing the considerably less sensitive, and labor-intensive combined first-trimester screening. These new technologies have opened potential new venues in the clinical management of this ominous late first-trimester sonographic diagnosis. Advances in cfDNA technologies are now permitting detection of chromosomal copy number variants (CNV) larger than 7Mb across genome and select serious single-gene disorders (mainly impacting skeletal and neurological development), affecting quality of life and may benefit from medical and/or surgical management. This commentary will address the available non-invasive prenatal screening technologies, which clearly enhance immediate genetic analysis modalities applicable in the presence of the complex sonographic finding of first-trimester septated cystic hygroma.

Fetal cystic hygroma in the first trimester led to diagnosis of partial trisomy 22

Partial trisomy 22 is a rare condition that is found in live birth. In most cases, diagnosis of partial trisomy 22 was made after birth. Herein, we report a prenatal diagnosis of fetal partial trisomy 22 in a 28-year-old pregnant woman presented with fetal cystic hygroma. Structural abnormalities were detected at 16 weeks of gestation: left cleft lip and ventricular septal defect. The G-banding karyotype analysis and fluorescence in situ hybridization showed partial trisomy 22. It is recommended that pregnant women with fetal anomalies should have prenatal genetic diagnosis to ascertain whether the fetus has partial trisomy 22 or other rare chromosomal abnormalities.

XYY Karyotype in a Mentally Retarded Man with Prognathism and Malformation of His Hands and Toe Nails

We report on a 25-year-old man who was referred for evaluation of possible Fragile X syndrome on the basis of mild mental retardation and malformation of his hands and toe nails. He was found not to have this syndrome but to have a 47, XYY karyotype. Only one other case of XYY syndrome with prognathism and malformation of hands has been reported.