Which statement about adrenal cortical dysfunction is correct?

The correct statement regarding adrenal cortical dysfunction is that Cushing's syndrome is associated with glucose intolerance. Cushing's syndrome results from prolonged exposure to elevated levels of cortisol, often due to either endogenous overproduction (such as from an adrenal tumor) or exogenous administration of glucocorticoids. This excess cortisol can lead to insulin resistance, which in turn contributes to glucose intolerance and can eventually result in diabetes mellitus if left unaddressed.

In contrast, the other statements present inaccuracies about adrenal disorders. For example, patients with Cushing's syndrome typically experience hypokalemia rather than hyperkalemia due to cortisol's mineralocorticoid-like effects, which promote sodium retention and potassium excretion. Addison's disease, characterized by insufficient cortisol production, is often associated with hyponatremia, not hypernatremia, as the lack of aldosterone secretion (which helps retain sodium) leads to decreased sodium levels. Additionally, Addison's disease is defined by low cortisol levels rather than elevated levels, which is fundamentally different from the condition of Cushing's syndrome. Therefore, the association of Cushing's syndrome with glucose intolerance is a crucial aspect of understanding its clinical implications.