HYPERALDOSTERONISM

Aldosterone is produced by zona glomerulosa in response to hyponatremia and hypovolemia, regulated by the renin-angiotensin system, and acts on renal tubules to increase sodium reabsorption.

Primary hyperaldosteronism is rare in childhood, caused by: (a) adenoma, (b) adrenal nodular hyperplasia or (c) congenital adrenal hyperplasia.

Clinically, it present with: (a) signs of sodium retention and hypernatremia, e.g. hypertension and polyuria, and (b) signs of excess potassium excretion and hypokalemia, e.g. muscular weakness, paresthesia alkalosis, etc. Oedema is absent in primary hyperaldosteronism due to aldosterone escape phenomenon wherein atrial natriuretic peptide causes natriuresis, preventing sodium retention and oedema.

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