Primary hyperaldosteronism

• Indications to test for mineralocorticoid excess in hypertensive patients include 

1. Hypokalaemia (including hypokalemia induced by thiazide diuretics), 
2. Poor control of blood pressure with conventional therapy, 
3. Family history of early-onset hypertension, 
4. Presentation at a young age. 

Clinical features 

• Usually asymptomatic 
• Sodium retention → oedema, HTN 
• Hypokalaemia: 

1. muscle weakness (even paralysis), 
2. polyuria (secondary to renal tubular damage, which produces nephrogenic DI) 
3. tetany (associated metabolic alkalosis and low ionized calcium). 

Investigations: 

Management 

• Mineralocorticoid receptor antagonists 
  • spironolactone and eplerenone: correction of hypokalemia and hypertension 
  • spironolactone→ (20% of males) develop gynaecomastia → alternative→  Amiloride 

• APA:

• Medical therapy is usually given for a few weeks to normalize whole-body electrolyte balance before unilateral adrenalectomy. 

• Surgery cures the biochemical abnormality 

• Hypertension may persist (70% of cases), probably because of irreversible damage to the systemic microcirculation