Primary aldosteronism is often caused by a tumor but secondary aldosteronism can have a number of causes including low salt intake, edematous conditions, and potassium loading.
While we cannot provide medical advice or guidance, the following information may be of interest (Pagana 2021):
Aldosterone, a hormone produced by the adrenal cortex, is primarily regulated by the renin-angiotensin system (RAAS) and secondarily by ACTH, low serum sodium, and high serum potassium levels. It helps regulate serum sodium and potassium levels by stimulating renal tubules to absorb sodium and secrete potassium. Aldosterone also plays a role in water absorption and plasma volume regulation.
Hyperaldosteronism is a condition where the adrenal cortex produces excessive aldosterone. Primary aldosteronism results from adrenal tumors or nodular hyperplasia, causing symptoms like hypertension and hypokalemia, while secondary aldosteronism stems from non-adrenal factors including:
- Edematous states (e.g., congestive heart failure, nephrotic syndrome)
- Hyponatremia (from diuretic or laxative abuse) or low salt intake
- Hypovolemia
- Malignant hypertension
- Potassium loading
- Pregnancy or use of estrogens
- Renal vascular stenosis or occlusion
Primary hyperaldosteronism can be diagnosed through aldosterone stimulation and suppression tests, which involve salt restriction and saline infusion, respectively. The aldosterone-to-renin ratio (ARR) is the most sensitive method for differentiating primary from secondary causes of hyperaldosteronism. An ARR persistently above 30 ng/dL per ng/mL/hour likely indicates primary aldosteronism.
Additional causes of secondary hyperaldosteronism include excessive activation of RAAS, LV heart failure, cor pulmonale, and cirrhosis accompanied by ascites (Dominguez 2022).
Please note that blood levels of aldosterone can vary based on physical positioning, i.e., levels are higher when taken upright versus being supine, and lab ranges can vary depending on position (Pagana 2021).
References
Dominguez, Alejandro, et al. “Hyperaldosteronism.” StatPearls, StatPearls Publishing, 12 February 2023.
Pagana, Kathleen Deska, et al. Mosby's Diagnostic and Laboratory Test Reference. 15th ed., Mosby, 2021.