Introduction
Aldosterone-producing adenoma commonly affects three to ten percent of the hypertensive population. Hypertension is a condition in which people suffer from high blood pressure. The alteration in the gene (mutation) coding potassium channel GIRK4-KCNJ5 is responsible for causing aldosterone-producing adenoma. The underlying reason for primary aldosteronism (PA) is aldosterone-producing adenomas (APA), described by Jerome Conn in the 1950s. The patient with aldosterone-producing adenomas suffers from hypokalemia, hypertension, and muscle weakness, potentially having excess aldosterone presumably released from the adrenal glands. Aldosterone-producing adenomas are diagnosed by aldosterone level, potassium level, and high blood pressure. An aldosterone-producing adenoma is a curable disease. The prevention of aldosterone-producing adenomas is still unknown.
What Is Aldosterone-Producing Adenoma?
Aldosterone is a hormone that is secreted by the adrenal gland. The adrenal gland is situated at the top of the kidney. The adrenal gland maintains salt balance in our blood and tissue, maintains blood pressure, and produces sex hormones. The disease in which the production of aldosterone is inappropriately high. An aldosterone-producing adenoma is also called primary aldosteronism, Conn's adenoma, or aldosteronism-producing cancer. Aldosterone causes the excretion of potassium into the urine and the uptake of sodium together with water, resulting in hypokalemia (low potassium level), increased blood volume, and hypertension (high blood pressure) in the case of aldosterone-producing adenomas. Aldosterone-producing adenoma (APA) refers to excessive aldosterone secretion in the body. The disease prevalence in European countries is about 38 % and higher in Asia. This is more prevalent in women and younger people. However, the prevalence of PA in adults is unknown.
The following are the types of aldosterone-producing adenoma:
Surgically Correctable Subtypes
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Aldosterone-producing adenoma.
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Renin or angiotensin unresponsive adenoma.
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Renin or angiotensin-responsive adenoma.
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Primary unilateral adrenal hyperplasia.
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Adrenocortical carcinoma with aldosterone hypersecretion.
Non-Surgically Correctable Subtypes
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Idiopathic adrenal hyperplasia.
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Familial hyperaldosteronism.
What Causes Aldosterone-Producing Adenoma?
Aldosterone is a hormone secreted in the adrenal gland's cells. The regulator of aldosterone release is angiotensin 2. Angiotensin 2 opens calcium channels, which increases the release of aldosterone. The mutation in the gene encoding the enzyme angiotensin two can cause the formation of a tumor (uncontrolled growing cell). The mutations p.Gly151Arg or p.Leu168Arg were the initial ones found to cause adenomas. The mutations cause alteration in the regulation of calcium channels, which in turn results in excessive release of aldosterone. The total number of mutations in KCNJ5 associated with sporadic PA is now about 20. There is also some evidence of germline mutation or functional mutation. The prevalence of KCNJ5 mutations in Asia is around 78 %. GNAS and PRKACA mutations are also found in APAs. The independent risk of aldosterone is oxidative stress, inflammation, and cell fibrosis.
What Are the Risk Factors?
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Hypertension (high blood pressure).
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Heart disease.
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Stroke (a condition in which blood vessels get blocked or blood clots occur).
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Left ventricular hypertrophy (a condition in which thickening of the heart's walls occurs).
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Atrial fibrillation (a condition where irregular heartbeat leads to a blood clot in the heart).
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Proteinuria (a condition in which there is a high level of protein in the urine).
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Hypokalemia (low potassium level in the body).
How to Diagnose Aldosterone-Producing Adenoma?
Diagnosing aldosterone-producing adenoma is important as patients with this disease have a risk of cardiovascular disease and hypertension. It can also damage multiple organs. The key to diagnosis is the aldosterone-renin level. Other biochemical tests are necessary for patients to avoid excessive and costly imaging tests.
The following are the investigations that can be done to diagnose aldosterone-producing adenoma:
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Aldosterone to Renin Ratio - The level of aldosterone increases—the renin levels increase by decreased sodium intake. The raised aldosterone to renin ratio confirms the disease, but it is a non-specific disease.
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Saline-Infusion Test - This test detects a high level of sodium.
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Urine Test - The aldosterone is detected in the urine.
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Computed Tomography Scan - The high lipid content in the adenomatous tumor cell is detected in a CT scan without contrast.
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Positron Emission Tomography (PET) - A PET scan can detect the size and location of the tumor.
How to Treat Aldosterone-Producing Adenoma?
The choice between medical management and surgery depends on various factors, including symptoms' severity, complications, tumor size, patient's overall health, and individual preferences. In general, surgery is considered the most effective treatment, as it directly addresses the underlying cause of the condition. The treatment of aldosterone-producing adenoma typically involves a combination of medical management and surgical intervention. Here are the main treatment options:
1. Medications
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Mineralocorticoid Receptor Antagonists: These drugs, such as Spironolactone or Eplerenone, block the effects of aldosterone help reduce blood pressure, and correct potassium imbalances.
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Blood Pressure Medications: Additional medications to control high blood pressure may be prescribed, such as angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), or diuretics.
2. Surgery
Surgical removal of the adenoma is the definitive treatment for aldosterone-producing adenoma. This procedure is called an adrenalectomy. Depending on the size and location, it involves removing the affected adrenal gland or the tumor itself. Adrenalectomy is typically performed using minimally invasive techniques, such as laparoscopic or robotic-assisted surgery.
In summary, managing aldosterone-producing adenomas requires a tailored approach, combining medical therapies to control symptoms and surgical intervention to address the underlying tumor. By effectively treating this condition, patients can achieve blood pressure control and restore the balance of electrolytes, improving their overall health and well-being.
Conclusion
In conclusion, aldosterone-producing adenomas, or Conn's syndrome, present a challenge in managing blood pressure and electrolyte imbalances. These small tumors in the adrenal glands overproduce the hormone aldosterone, leading to hypertension and disruptions in potassium and sodium levels. The treatment of aldosterone-producing adenomas typically involves a combination of medication and surgery. Medication options include mineralocorticoid receptor antagonists, which block the effects of aldosterone, and other blood pressure medications to control hypertension. However, surgery, specifically adrenalectomy, is considered the definitive treatment. By removing the affected adrenal gland or tumor, surgical intervention directly addresses the condition's root cause. Treatment choice depends on various factors, including symptom severity, complications, tumor size, overall health, and patient preferences. Consulting with an endocrinologist or adrenal specialist is crucial for accurate diagnosis, appropriate diagnostic tests, and the development of an optimal treatment plan.
