What condition is marked by excessive secretion of aldosterone?

The condition characterized by excessive secretion of aldosterone is Conn's Syndrome, also known as primary hyperaldosteronism. In this condition, the adrenal glands produce an abnormal amount of aldosterone, a hormone responsible for regulating sodium and potassium levels in the body, as well as maintaining blood pressure.

The primary effect of elevated aldosterone levels is sodium retention, which leads to fluid retention and subsequently increased blood volume and blood pressure. Additionally, excessive aldosterone results in the loss of potassium, which can lead to hypokalemia (low potassium levels in the blood) and may cause symptoms such as muscle weakness and cramps.

In contrast, the other conditions listed are not primarily associated with aldosterone secretion. Pheochromocytoma involves the overproduction of catecholamines, leading to symptoms related to adrenaline surges. Cushing’s Syndrome is marked by excessive cortisol production, resulting in a variety of metabolic effects but not specifically aldosterone. Addison’s Disease, on the other hand, is characterized by insufficient hormone production from the adrenal glands, including aldosterone, leading to low blood pressure and electrolyte imbalances. Thus, Conn's Syndrome is uniquely defined by its link to excessive aldosterone secretion.