Metanephrines, URINE-24 HOURS test is a diagnostic tool used to measure the levels of metanephrines in a patient’s urine over a 24-hour period. Metanephrines are breakdown products of catecholamines, which are hormones produced by the adrenal glands. High levels of metanephrines in the urine can be a sign of a tumor or other abnormal growth in the adrenal gland or in other parts of the body that produce these hormones. This test is commonly used to diagnose conditions such as pheochromocytoma, a rare tumor that produces excess catecholamines. The 24-hour collection period is necessary to ensure accurate results as the levels of metanephrines can vary throughout the day. This test is a valuable tool for diagnosing conditions related to the adrenal gland and is often used in conjunction with other diagnostic tests.