What is the primary cause of Conn's syndrome?

Conn's syndrome, also known as primary hyperaldosteronism, is predominantly caused by excessive secretion of aldosterone, which can be most commonly attributed to an aldosterone-producing adenoma. This type of tumor arises from the adrenal cortex and leads to unregulated synthesis and release of aldosterone, resulting in hypertension and metabolic disturbances such as hypokalemia.

While bilateral adrenal hyperplasia is also a recognized cause of Conn's syndrome, the condition primarily refers to the presence of an adenoma as the leading cause in many cases. Other potential causes of increased aldosterone production, such as adrenal carcinoma or conditions like Cushing’s syndrome, do not primarily fall under the definition of Conn’s syndrome and are less common.

Understanding the pathophysiology of Conn's syndrome highlights the importance of aldosterone in regulating sodium retention and potassium excretion, and it underscores why an aldosterone-producing adenoma is the most frequent culprit in clinical presentations of this disorder.