New PAX2 Mutation Associated with Polycystic Kidney Disease: A Case Report.

Congenital anomalies of the kidney and urinary tract (CAKUT) are the leading cause of end stage renal disease in children. Diagnosis by genetic testing has proven challenging due to its genetic and phenotypic heterogeneity, as well as incomplete penetrance. We report a case on a 16-months old female with a history of renal cysts and a PAX2 mutation. The patient presented with a prenatal diagnosis of Potter sequence and a postnatal diagnosis of renal cysts. An ultrasound at 20 weeks gestation revealed right renal agenesis and possible left renal dysplasia. Post natal genetic analyses identified a novel mutation in PAX2. Cystic kidney disease is often underdiagnosed due to its variable expressivity and wide range of clinical manifestations; PAX2 genetic screening should be considered for all patients with CAKUT.