[Dwarfism, arterial hypertension and hyperkalemic acidosis corrected with thiazides. A case of type II pseudohypoaldosteronism].

Background: Type II pseudohypoaldosteronism is a rare tubulopathy defined by abnormal renal potassium excretion.

Case Report: A 12 1/2 year-old girl, was admitted for dwarfism. Her parents were not consanguineous and her 5 living sibs were normal. At admission, she had moderate hypertension: systolic 130-150 mmHg; diastolic 80-100 mmHg and no pubertal development.

Laboratory Data: pH (arterial): 7.34; bicarbonates: 18-20 mEq/l; chloride: 112-120 mEq/l; potassium: 5.6-7 mEq/l; aldosterone: 200-700 pg/ml (N < 60); plasma renin activity: 0.4 ng/ml/hr (N 2.2 +/- 0.2). The bone maturation was 8 1/2 years. All the other renal function tests were normal. The titratable acidity was 22 mEq/day (N 20-40) and the ammonia excretion 15.2 mEq/l (N 44-61). The fractional excretion of potassium was 6.5% (N 11.8 +/- 1.9). This girl was given polystyrene sulfonate resin followed by hydrochlorothiazide (1 to 3 mg/kg/day). There was a subsequent improvement in all data, a growth spurt and pubertal development.

Conclusion: This is the fifth case of type II pseudohypoaldosteronism reported in childhood and the first one with hypertension. The beneficial effect of hydrochlorothiazide is underlined.