Congenital nephrotic syndrome with prolonged renal survival without renal replacement therapy.

BACKGROUND: Infants with congenital nephrotic syndrome (CNS) develop severe nephrotic syndrome that is resistant to medical therapy, and bilateral nephrectomy is recommended toward the end of the first year of life followed by renal replacement therapy. CNS infants in New Zealand have been observed to exhibit a different course to those with the typical Finnish mutation.

METHODS: A database of CNS children at our center was retrospectively examined. All cases diagnosed between 1975 and 2011 were reviewed. Demographic data, clinical features, genetic mutations, treatment, and outcome were extracted from clinical records.

RESULTS: Thirty-five patients with CNS, 23 children of Maori descent, and 12 Caucasians . Fourteen had died of either bacterial sepsis or intracranial thrombosis. Maori children had displayed a highly variable and protracted timeline to end-stage renal disease (ESRD) with median renal survival of 30 years versus 0.7 years in Caucasian patients. Mutation analysis of NPHS1 showed a founder mutation in the Maori population.

CONCLUSIONS: Congenital nephrotic syndrome in New Zealand Maori children exhibit a different clinical course to Caucasian children and have a mutation that was first described in this ethnic group.