What is the initial treatment for Conn's syndrome?

Initial Treatment for Conn's Syndrome (Primary Aldosteronism)

Treatment Algorithm Based on Disease Lateralization

The initial treatment for Conn's syndrome depends entirely on whether the disease is unilateral or bilateral, which must be determined through adrenal vein sampling or functional imaging with radiolabeled tracers before initiating definitive therapy. 1

For Unilateral Primary Aldosteronism (Conn's Adenoma)

• Laparoscopic adrenalectomy of the affected adrenal gland is the treatment of choice for unilateral disease, as it offers potential cure 1, 2, 3
• Surgery should be considered unless the patient is elderly or has significant comorbidities that increase surgical risk 1
• Preoperative preparation requires adequate blood pressure control and correction of hypokalemia with mineralocorticoid receptor antagonists (MRAs) before proceeding to surgery 3, 4

Important caveat: Even after successful surgery, approximately 43-45% of patients will have persistent hypertension due to vascular remodeling from delayed diagnosis, though the number of antihypertensive medications typically decreases substantially 1, 5, 6

For Bilateral Primary Aldosteronism or Non-Surgical Candidates

• Spironolactone is the first-line medical therapy, starting at 50-100 mg once daily 1, 2
• The dose can be titrated up to 300-400 mg once daily if necessary to achieve blood pressure control and normokalemia 1, 2
• This represents lifelong medical treatment, as bilateral disease is not surgically curable 1, 2, 3

Alternative MRA Options

• Eplerenone is an alternative MRA that causes less gynaecomastia and erectile dysfunction in men compared to spironolactone, though it is less potent and requires twice-daily administration 1
• For patients in whom spironolactone is not effective or tolerated, eplerenone should be considered as a replacement 1
• Newer non-steroidal MRAs (finerenone, exarenone) and aldosterone synthase inhibitors (baxdrostat) are being tested but are not yet standard therapy 1

Critical Monitoring Requirements

• Serum potassium and creatinine must be monitored closely when initiating spironolactone, especially in patients with reduced renal function, as hyperkalemia is a significant risk 1, 2, 4
• Start monitoring within days of medication initiation and continue at regular intervals during dose titration 4
• Blood pressure should be optimized before measuring the aldosterone-renin ratio for diagnosis, ideally with the patient at rest and with equilibrated potassium balance 3, 4

Refractory Cases

• For resistant hypertension despite optimal spironolactone dosing, adding a converting enzyme inhibitor (such as captopril) to spironolactone can provide additional blood pressure control by further suppressing the renin-angiotensin system 7
• If MRAs remain ineffective or poorly tolerated, consider adding a beta-blocker, centrally acting agent, alpha-blocker, or other potassium-sparing diuretic 1

Special Consideration: Familial Forms

• Glucocorticoid-remediable aldosteronism (familial hyperaldosteronism type 1) is uniquely treated with low-dose dexamethasone, which can be safely used even during pregnancy 1
• This requires genetic testing for germ-line mutations and family history assessment 1

Why Early Treatment Matters

• Early diagnosis and treatment improve cure rates and reduce target organ damage including left ventricular hypertrophy, albuminuria, and carotid intima-media thickness 2
• Delayed diagnosis leads to vascular remodeling that affects renal function and accounts for residual hypertension even after appropriate treatment 1, 2
• Primary aldosteronism carries increased cardiovascular risk and comorbidities including type 2 diabetes mellitus beyond the effects of hypertension alone 3

Referral Indications

• Complex cases or rare forms of primary aldosteronism should be referred to specialized hypertension centers for optimal management 1, 2