Which of the following conditions is characterized by high levels of urinary metanephrines?

Phenochromocytoma is a rare tumor of the adrenal glands that produces excessive catecholamines, which include epinephrine and norepinephrine. This condition leads to elevated levels of metanephrines—specifically metanephrine and normetanephrine—in the urine, as these are the metabolites of catecholamines. The measurement of urinary metanephrines is a critical diagnostic tool for detecting pheochromocytomas, as individuals with this condition will typically excrete higher levels than those without it.

In contrast, while hypertension, primary hyperaldosteronism, and Cushing's syndrome can all impact hormone levels and blood pressure, they do not specifically result in elevated urinary metanephrines. Hypertension can have various causes, and while it may sometimes be secondary to other conditions, it is not characterized by increased metanephrine levels. Primary hyperaldosteronism is associated with excess aldosterone and does not affect catecholamine metabolism. Cushing's syndrome, characterized by excess cortisol, also does not typically result in increased urinary metanephrines. Thus, when elevated urinary metanephrines are present, pheochromocytoma is the most relevant and significant condition to consider, leading to its identification as the correct