Page 1 of 3 Chromosome 16 Mutations and Congenital Genitourinary Malformations Daniel Faustin, Morgan Barlow*, Anuja Trivedi and Naila Ferris Wyckoff Heights Medical Center, USA Introduction Posterior urethral valve (PUV) disorder is an obstructive anomaly of the genitourinary tract. Found only in males, this condition is caused by an obstructing membrane in the posterior valve of the urethra. During the early stages of embryogenesis, the most caudal end of the wolffian duct is absorbed into the primitive cloaca, forming the posterior urethral folds [1]. In fetuses with PUV, the development of these structures is arrested resulting in fusion of these primitive folds, leading to an obstruction of the outflow of urine. This pathologic finding presents on a spectrum of varying degrees, wherein the obstruction may cause only mild symptoms and present as late as early infancy or cause severe and irreversible damage during early fetal development. In this case, we investigate the possible association between chromosome 16 and the development of the renal system, and the potential for congenital malformation in the setting of genetic alteration. Case We describe a 30-year-old G1P0 with a fetus that has multiple congenital anomalies and a chromosome 16 duplication at 16q24.2. This patient initially presented to our institution at 12 weeks gestation without any obstetrical complaints. She had no past medical or surgical history and no family history of congenital or chromosomal abnormalities. Initial sonogram revealed a viable fetus. Prenatal labs were found to be within normal limits, aside from a positive quantiferon gold. Fetal anatomy survey performed at 20 weeks gestation revealed multiple fetal anomalies, including bilateral cystic dilation of the pelvic and calyceal spaces, bilateral hydronephrosis, an enlarged urinary bladder, and oligohydramnios. Several sonographic images suggested a dilated posterior urethra, demonstrated by the pathognomonic “keyhole appearance”. PUV was suspected at this time and close follow-up was recommended. The patient was evaluated again at 22 weeks gestation, and a targeted fetal ultrasound revealed worsening oligohydramnios with persistent distention of the urinary system. These findings confirmed the suspicion of posterior urethral valve disorder. Figure 1: Fetal bladder with “keyhole” appearance. Figure 2: Fetal bladder with “keyhole” appearance, alternate view. The patient was counseled on the findings and expectations of this anomaly during the anatomy scan and genetic testing was offered. Amniocentesis showed elevated AFP (23.1 mcg/mL) *Corresponding author: Morgan Barlow, Wyckoff Heights Medical Center, Department of OB/Gyn, USA Received Date: November 13, 2018 Published Date: November 20, 2018 ISSN: 2641-6247 DOI: 10.33552/WJGWH.2018.01.000511 World Journal of Gynecology & Women’s Health Case Report Copyright © All rights are reserved by Morgan Barlow This work is licensed under Creative Commons Attribution 4.0 License WJGWH.MS.ID.000511.