Clinical manifestation and molecular analysis of three Korean patients with the renal form of pseudohypoaldosteronism type 1

Pseudohypoaldosteronism (PHA) type 1 is a rare, heterogeneous disease characterized by hyponatremia and hyperkalemia due to mineralocorticoid resistance. The clinical features of PHA are usually failure to thrive, vomiting, and dehydration in the neonatal period. Heterozygous mutations in the Nuclear receptor subfamily 3, group C, member 2 (NR3C2) gene result in the dominant renal form of PHA type 1. Mutations in the epithelial sodium channel gene result in the more severe, recessive, systemic form of PHA type 1. Here, we describe the clinical and biochemical characteristics of three sporadic cases from two Korean families diagnosed with the renal form of PHA type 1. Mutation analysis of the NR3C2 gene revealed one novel mutation in twin patients and two functional polymorphisms in one patient with unusual clinical symptoms. Our data contribute to a better understanding of the distinct mutations and clinical manifestations of the renal form of PHA type 1.