Expanding the clinical spectrum of autosomal‐recessive renal tubular dysgenesis: Two siblings with neonatal survival and review of the literature

BACKGROUND: Autosomal‐recessive renal tubular dysgenesis (AR‐RTD) is a rare genetic disorder caused by defects in the renin‐angiotensin system that manifests as fetal anuria leading to oligohydramnios and Potter sequence. Although the most common outcome is neonatal death from renal failure, pulmonary hypoplasia, and/or refractory arterial hypotension; several cases have been reported that describe survival past the neonatal period. METHODS: Herein, we report the first family with biallelic ACE variants and more than one affected child surviving past the neonatal period, as well as provide a review of the previously reported 18 cases with better outcomes. RESULTS: While both siblings with identical compound heterozygous ACE variants have received different treatments, neither required renal replacement therapy. We show that both vasopressin and fludrocortisone in the neonatal period may provide survival advantages, though outcomes may also be dependent on the type of gene variant, as well as other factors. CONCLUSION: While AR‐RTD is most often a lethal disease in the neonatal period, it is not universally so. A better understanding of the factors affecting survival will help to guide prognostication and medical decision‐making.