Phase II Study of the Pathophysiology and Treatment With Enalapril and Polystyrene Sulfonate for Pseudohypoaldosteronism, Type I

PROTOCOL OUTLINE: Sodium and potassium intake resulting in normalization of serum electrolytes and markers of extracellular volume are determined at baseline. A trial diet is then prescribed, with adjustments made to achieve a steady state with normal serum electrolytes. Exercise tolerance and muscle function are evaluated at steady state. Sodium and potassium are sequentially manipulated with diet, enalapril, and polystyrene sulfonate. Exercise tolerance is evaluated during each diet period. A treatment plan to maintain electrolyte balance is developed. The patient is followed monthly for 3 to 6 months, then every 3 months for up to 3 years.