Case report: severe neonatal hyperkalemia due to pseudohypoaldosteronism type 1.

Hyponatremia and hyperkalemia in infancy can represent a variety of renal and genetic disorders with significant long-term health implications. We report a newborn with severe hyperkalemia and hyponatremia from autosomal recessive pseudohypoaldosteronism type 1 requiring aggressive therapy. The evaluation and treatment of children with disorders of mineralocorticoid action are discussed.