Improving renal phenotype and evolving extra-renal features of 17q12 deletion encompassing the HNF1B gene

• Published in: Translational pediatrics 2021-12, Vol.10 (12), p.3130-3139
• Main Authors: Cleper, Roxana, Reches, Adi, Shapira, Dana, Simchoni, Sharon, Reisman, Lewis, Ben-Sira, Liat, Yaron, Yuval, Wolman, Igal, Malinger, Gustavo, Brabbing-Goldstein, Dana, Ben-Shachar, Shay
• Format: Article
• Language: English
• Subjects: Original
• ISSN: 2224-4344; 2224-4336; 2224-4344
• DOI: 10.21037/tp-21-386

deletion/intragenic mutations are the most commonly identified genetic cause of congenital anomalies of the kidney and urinary tract (CAKUT) suggested by fetal ultrasound findings such as: parenchymal hyperechogenicity, overt cystic changes or gross morphological urinary system (UT) abnormalities. The postnatal evolution of these 17q12 deletions encompassing the gene-associated findings has not been assessed in depth. In this observational study, we present postnatal follow-up findings in 5 of 6 cases (one pregnancy was terminated on parental request) of fetal-onset cystic/hyperechogenic kidneys eventually diagnosed with 17q12 microdeletion encompassing the gene between 2009 and 2017. Complete normalization of kidney parenchymal abnormalities and of depressed neonatal renal function was observed in 4/5 and 5/5 patients within 2-4.9 years and 1.5-8 months, respectively. All 5 patients had preserved normal renal function at 3-11 years of follow-up. The evolving later-onset renal features included: hypomagnesemia, hyperuricemia, urinary tract infection (UTI), and bilateral grade 3-4 vesicoureteral reflux and bladder diverticula in 3, 3, 2, and 1 patient, respectively. gene deletion-associated extra-renal manifestations with delayed presentation were global developmental delay/autistic spectrum disorder (ASD), rolandic-type seizures, overweight, and borderline fasting hyperglycemia observed in 1-2 patients each. Family history was positive for small-size or asymptomatic cystic kidneys with normal function, diabetes mellitus, seizures, and mental/psychiatric problems in 3/6 cases. Fetal-onset deletion-associated kidneys' parenchymal abnormalities confirmed postnatally with initially depressed renal function might undergo complete resolution within several years and few months, respectively. However, later-onset urinary tract, metabolic, and neurodevelopmental features of this mutation might appear over years. Therefore, genetic molecular evaluation/diagnosis and continuous follow-up for evolving features are mandatory in affected children.