Abstract
Objective
To describe the prenatal and postnatal diagnostic workup leading to the diagnosis of 5-alpha-reductase type 2 deficiency (5AR2D) in a case of 46,XY disorder of sex development (DSD).
Case report
A first-trimester noninvasive prenatal test (NIPT) on maternal blood revealed a male fetus with a low risk of aneuploidy. However, a female fetus was identified at the second-trimester scan. A repeat sample revealed similar results and ruled out the possibility of both a sample swap or a vanishing twin. At birth, phenotypically female external genitalia were evident, with testes noted in the labioscrotal area. Neonatal blood confirmed a 46,XY complement and a 46,XY DSD genetic panel revealed a 5AR2D.
Conclusion
Our case and others described in the literature demonstrate that fetal sex discordance detected by a combination of NIPT and subsequent ultrasound examination can be associated with several biological conditions, with DSD being the most significant.
Disclosure statement
The authors declared no potential conflicts of interest with regards to the research, authorship, and/or publication of this article. FETALMED has a contract agreement with Natera Inc. for the commercialization of NIPT in its clinical practice.
Ethical statement
The ultrasound protocols and diagnostic procedures performed in this patient were approved by the corresponding Institutional Review Boards. Obstetrical ultrasound examinations and the corresponding clinical follow-up in cases when abnormal findings were detected prenatally are performed as part of our standard clinical care. The patient consented to the ultrasound examination and NIPT analyses. Due to the retrospective nature of this study, permission of the Ethics Committee was waived.