Acquired pseudohypoaldosteronism is a rare secondary disorder of electrolyte equilibrium defined as a state of resistance to aldosterone in renal tubules. It typically develops in infants but may occur in any age group following a urinary tract infection or renal transplant or in a patient with a urinary tract abnormality. Patients experience hyponatremia from the severe volume depletion of urinary salt wasting, hyperkalemia, hydronephrosis, metabolic acidosis, and weight loss. Plasma aldosterone levels may be normal or elevated, and renin levels are elevated. Target tissues develop resistance to mineralocorticoids. This resistance results in aldosterone having a markedly diminished effect on its targeted receptors. Usually, renal and adrenal functions are normal.
Twenty percent of pseudohypoaldosteronism cases are due to familial causes; the acquired form is discussed here.
Treatment involves eliminating the underlying cause and providing supportive care for the associated electrolyte disturbances.