Prenatal diagnosis of 22q11.2 deletion syndrome associated with right aortic arch, left ductus arteriosus, cardiomegaly, and pericardial effusion

Prenatal diagnosis of genetic aberrations in fetuses with pulmonary stenosis in southern China: a retrospective analysis

BACKGROUND

The genetic etiology of congenital pulmonary stenosis (PS) in fetuses remains inadequately studied. We used karyotype analysis and chromosomal microarray analysis (CMA) to investigate the genetic aberrations associated with PS in human fetuses.

METHODS

A retrospective analysis was performed on 84 fetuses with congenital PS in southern China. Fetal amniotic fluid and umbilical cord blood samples were obtained for chromosomal karyotype analysis and CMA.

RESULTS

The rate of pathogenic copy number variation (CNV) was 15.5% (13/84) after karyotyping and CMA. An abnormal karyotype was detected in five cases (6.0%, 5/84) via karyotyping, whereas pathogenic CNVs were detected in 13 cases (15.5%, 13/84) via CMA. In addition to the five abnormal karyotypes detected using karyotype analysis, eight additional chromosomal microduplications and microdeletions were detected using CMA, comprising three cases of 22q11.21 microdeletion; two cases of 16p11.2 microdeletion; one case of simultaneous 18q23 microdeletion and 22q13.33 microduplication; one case of 15q24.1q24.2 microdeletion; and one case of 1q21.1q21.2 microduplication. The rate of pathogenic CNV occurrence was 11.5% in fetuses with isolated PS and 17.2% in fetuses with PS combined with other ultrasound abnormalities. This difference between the two experimental groups was statistically significant. Among 84 fetuses with PS, 39 pregnancies were terminated, and five were lost to follow-up.

CONCLUSIONS

CMA was not only conducive to detect PS-related pathogenic genomic abnormalities but also to accurately evaluate fetal prognosis in genetic counseling. The early detection of PS and genomic abnormalities will exerta positive impact on fetal intervention and the related prognosis of PS in perinatal infants.

Prenatal diagnosis of familial 22q11.2 deletion syndrome in a pregnancy with concomitant cardiac and urinary tract abnormalities in the fetus and the mother

OBJECTIVE

We present prenatal diagnosis of familial 22q11.2 deletion syndrome in a pregnancy with concomitant cardiac and urinary tract abnormalities in the fetus and the mother.

CASE REPORT

A 28-year-old woman primigravid underwent amniocentesis at 23 weeks of gestation because of fetal ultrasound findings of aortic stenosis, interrupted aortic arch (IAA), left multicystic kidney, right hydronephrosis and ureterocele. Amniocentesis revealed a karyotype of 46,XX. Simultaneous array comparative genomic hybridization (aCGH) analysis on the DNA extracted from uncultured amniocytes revealed the result of arr 22q11.21 (18,894,835-21,505,417) × 1.0 [GRCh37 (hg19)] with a 2.611-Mb 22q11.21 deletion encompassing 41 Online Mendelian Inheritance in Man (OMIM) genes including UFD1L, TBX1, GNB1L, COMT and MED15. aCGH analysis on the DNAs extracted from parental bloods confirmed that the mother carried the same 22q11.21 microdeletion. Level II ultrasound additionally found ventricular septal defect (VSD) and persistent left superior vena cava (PLSVC). Examination of the woman showed short stature, malar hypoplasia, hypertelorism, bulbous nasal tip, prominent nasal root, hypoplasia of nasal wings, right renal agenesis, left ureterovesical reflux and VSD with repair, but normal intelligence and normal neuropsychiatric development. The woman decided to continue the pregnancy, and a 2903-g female baby was delivered at 38 weeks of gestation with left multicystic kidney, right hydronephrosis, dysgenesis of corpus callosum, IAA, VSD, PLSVC, patent ductus arteriosus, patent foramen ovale, atrial septal defect, dilated main pulmonary artery and tricuspid regurgitation. The neonate died at the age of one month.

CONCLUSION

Prenatal diagnosis of concomitant congenital heart defects and urinary tract abnormalities in the fetus and the parent should raise a suspicion of familial 22q11.2 deletion syndrome.

[Isolated right aortic arch: prenatal diagnosis characteristics, pregnancy outcomes and systematic review]

OBJECTIVE

To investigate prenatal diagnosis characteristics and pregnancy outcomes associated with isolated right aortic arch (RAA).

METHODS

A retrospective study including fetuses with isolated RAA, managed between January 2010 and February 2018. Cases were identified from the ultrasound databases of the expert pediatric cardiologists, who made the aforementioned diagnosis. All fetuses were examined by a fetal medicine imaging expert to exclude any extracardiac abnormality. A systematic review was performed to assess the prenatal diagnosis and outcomes of fetuses with isolated RAA.

RESULTS

Fifty-six fetuses were diagnosed with an isolated RAA. An isolated double aortic arch (DAA) was diagnosed in one fetus. Mean gestational age at diagnosis was 24 weeks. The sex ratio (boy/girl) was 0.89. No significant abnormality was detected in invasive tests (karyotype and FISH or microarray). Only one fetus was misdiagnosed with isolated RAA. He was the only symptomatic (stridor) newborn baby and was later diagnosed with DAA. Four studies were included in our systematic review representing 115 cases of isolated RAA. One significant chromosomal abnormality was detected: a 22q11 deletion in a newborn baby who had a postnatal finding of a soft palate cleft. There was one major obstetric complication: an intrauterine fetal demise at 41 gestational weeks.

CONCLUSION

Diagnosis of isolated RAA can be challenging. Invasive tests are to be discussed. The diagnosis of isolated RAA should not change obstetric monitoring. Nevertheless, an echocardiography should be performed systematically in these new newborn babies within their first month of life.