Hyperaldosteronism

Background

Hyperaldosteronism refers to a condition of excess aldosterone secretion, typically leading to sodium retention, potassium excretion, and metabolic alkalosis. It is categorized into:

• Primary hyperaldosteronism (Conn syndrome) – autonomous overproduction of aldosterone, most commonly from an adrenal adenoma or bilateral adrenal hyperplasia.
• Secondary hyperaldosteronism – due to increased renin from conditions like renal artery stenosis, heart failure, or cirrhosis.

Primary hyperaldosteronism is an important and potentially reversible cause of secondary hypertension, accounting for 5–10% of hypertensive cases and up to 20% of treatment-resistant hypertension. It is often underdiagnosed in emergency settings.

Clinical Features

• Hypertension (often severe or resistant)
• Hypokalemia, which may manifest as:
  • Weakness
  • Fatigue
  • Muscle cramps
  • Constipation
  • Paresthesia
• Polyuria and polydipsia
• Metabolic alkalosis (less commonly symptomatic)
• Headache or nonspecific complaints
• Asymptomatic in some patients

Differential Diagnosis

• Essential hypertension
• Cushing’s syndrome
• Pheochromocytoma
• Renal artery stenosis
• Diuretic or laxative use
• Liddle syndrome
• Bartter/Gitelman syndromes
• Chronic licorice ingestion

Evaluation

Workup

Consider hyperaldosteronism in ED patients with:

• Severe or refractory hypertension
• Unexplained hypokalemia
• Metabolic alkalosis

Recommended ED labs:

• Electrolytes (noting hypokalemia and alkalosis)
• Creatinine/BUN
• ECG (look for U waves, flattened T waves, arrhythmias)
• ABG or venous blood gas (if alkalosis suspected)
• Urine potassium (if available)