Year: 2020
Type: conference-abstract
Abstract: Aberrant right subclavian artery (ARSA) is the most common congenital abnormality of the aortic arch and occurs in about 0.5−2% of the normal population. Usually, when isolated, ARSA is considered a normal variant rather than a true defect. However, there is an important association with chromosomal abnormalities, cardiac defects and genetic anomalies. The most frequent genetic abnormalities associated with ARSA are chromosomal aberrations, especially Trisomy 21 and Trisomy 18. We report a case of a mosaic Turner Syndrome detected by karyotype analysis performed due to ARSA as an isolated sonographic finding. A 28year-old woman, primigravida, started pregnancy surveillance only at 22 weeks. The first ultrasound, at 23 weeks, revealed an ARSA, without other changes. After genetic counselling, the parents opted for karyotype analysis and FISH for 22q11 deletion that revealed a mosaic 45XO/46XX, with about 19% of the cells in monosomy. At 36th week of gestation, the estimated fetal weight was in the 4th percentile with abnormal Doppler blood flow in middle cerebral artery and umbilical artery. An induction of labour was decided a week later and an 2225gr female infant with Apgar score of 9/10 was delivered by vaginal delivery. Postnatal examination and echocardiography confirmed that ARSA was the only finding in the fetus. Turner's syndrome is a relatively common chromosomal disorder occurring in approximately 1 in 2000 live births. The syndrome is caused by complete or partial absence of the second X chromosome, with or without cell line mosaicism. The most serious clinical aspect of this syndrome is due to congenital cardiovascular anomalies, in particular elongation of the transverse arch and aort coarctation. Mosaic monosomy X has been associated with a significant lower incidence of major cardiovascular anomalies. The performance of a fetal karyotype test when ARSA is an isolated finding is still a debatable issue, however it should be discussed with the parents.
DOI: 10.1002/uog.22806
Institution: Unidade Hospitalar de Famalicão
Language: English
Subfield: Genetics
Domain: Life Sciences
Open Access status: bronze
OpenAlex ID: W4244576585