Primary hyperaldosteronism

Background

• XS aldosteronism - Na⁺ retention, hypertension and hypokalaemia
• Rare (< 1%) causes of hypertension
• Adrenal adenoma = Conn’s synd = 60% primary hyperaldosteronism (hyperplasia)
• Adenomas in young women, bilateral hyperplasia in older men

Diagnosis

• ↑ (>30mmol/day) urinary K⁺ loss → hypokalaemia
• High aldosterone levels not suppressed by saline or fludrocortisone
• Suppressed renin activity (beware β-blockers may do similar)
• Then CT or venous catheterisation

Secondary Hyperaldosteronism

• XS renin and so angiotensin 2 causing stimulation of zona glomerulosa
• Causes - accelerated hi BP, renal art stenosis
• Causes in normal BP = CCF and cirrhosis etc
• Spironolactone useful in both
• ACEI (e.g. Captopril ) good for failure