[Pseudo-Bartter syndrome without hypopotassemia: a case with unilateral multicystic dysplastic kidney and congenital contralateral hyronephrosis].

A 2-month-old girl having a left multicystic dysplastic kidney with contralateral mild hydronephrosis is described. Furosemide was administered orally because of hyperpotassemia during the period between 1 month and 7 months of age. Peripheral plasma renin activity and plasma aldosterone activity increased at the age of 6 months, and ultimately reached the peak at 9 days after discontinuation of furosemide at the age of 7 months. Peripheral plasma renin activity and plasma aldosterone activity were normalized at the age of 11 months. Blood pressure during the whole period was normal. Contralateral hydronephrosis was improved gradually. The level of serum creatinine became normal at the age of 50 days. A case with a high level of plasma renin and aldosterone activity temporarily induced by furosemide was reported. Pathophysiology of pseudo-Bartter syndrome without hypopotassemia due to furosemide is discussed.