What is the initial treatment for primary aldosteronism?

Initial Treatment for Primary Aldosteronism

For primary aldosteronism, the initial treatment depends on whether the condition is unilateral or bilateral: laparoscopic adrenalectomy is the first-line treatment for unilateral disease, while mineralocorticoid receptor antagonists (MRAs) such as spironolactone or eplerenone are the first-line treatment for bilateral disease. 1

Treatment Algorithm Based on Subtype

Step 1: Determine the Subtype

Before initiating treatment, it's essential to determine whether the patient has:

• Unilateral disease: Aldosterone-producing adenoma (APA) or unilateral adrenal hyperplasia
• Bilateral disease: Bilateral adrenal hyperplasia (idiopathic hyperaldosteronism)

This differentiation requires adrenal vein sampling (AVS) in most cases, though some institutions exclude AVS in patients younger than 40 years when imaging shows only one affected gland 1.

Step 2: Treatment Based on Subtype

For Unilateral Disease:

• Primary treatment: Laparoscopic adrenalectomy 1
  • Improves blood pressure in virtually 100% of patients
  • Completely cures hypertension in approximately 50% of patients
  • Preoperative preparation may include spironolactone to control hypertension and hypokalemia

For Bilateral Disease:

• Primary treatment: Mineralocorticoid receptor antagonists 1, 2
  • Spironolactone: Start at 12.5-25 mg daily, titrate up to 100 mg daily as needed
  • Eplerenone: Alternative option, particularly for patients experiencing sexual side effects with spironolactone
  • For long-term maintenance therapy, use the lowest effective dosage determined for the individual patient 2

Medication Details

Spironolactone

• Dosage for primary hyperaldosteronism: 100-400 mg daily for preoperative preparation; for long-term maintenance, use lowest effective dose 2
• Administration: Can be taken with or without food, but should be taken consistently with respect to food 2
• Side effects: Gynecomastia, breast tenderness in men, menstrual irregularities in women, sexual dysfunction, and hyperkalemia 1, 3
• Monitoring: Check serum potassium and renal function within 1-2 weeks of starting therapy, then at 3 days and 1 week, then monthly for the first 3 months 1

Eplerenone

• Advantages: More selective aldosterone receptor antagonist with fewer endocrine side effects than spironolactone 3
• Dosage: 50-100 mg daily 4
• Best for: Patients experiencing sexual side effects with spironolactone 1

Special Considerations

For Patients Unsuitable for Surgery

• Even with unilateral disease, if a patient is not a surgical candidate, long-term MRA therapy is appropriate 2
• Spironolactone can be used as long-term maintenance therapy at the lowest effective dosage 2

For Inadequate Blood Pressure Control with MRAs

• Consider adding:
  • Potassium-sparing diuretics (amiloride or triamterene)
  • Calcium channel antagonists 4

Monitoring During Treatment

• Regular assessment of blood pressure control
• Periodic measurement of serum potassium and renal function
• Watch for side effects such as gynecomastia, sexual dysfunction, and menstrual irregularities 1

Clinical Pitfalls to Avoid

1. Delayed diagnosis: Vascular remodeling from delayed diagnosis may result in residual hypertension even after treatment, highlighting the importance of early diagnosis and treatment 1

2. Inadequate monitoring: Failure to monitor potassium levels can lead to dangerous hyperkalemia, especially when MRAs are combined with ACE inhibitors 1

3. Overlooking bilateral disease: The majority of primary aldosteronism cases (approximately 50%) are due to bilateral adrenal hyperplasia and require medical rather than surgical management 5

4. Insufficient preoperative preparation: For surgical candidates, inadequate control of hypertension and hypokalemia preoperatively can increase surgical risks

5. Inappropriate medication dosing: Starting with too high a dose of spironolactone can lead to unnecessary side effects; begin with lower doses and titrate as needed 1, 4