Metanephrines Blood Test
Metanephrines Blood Test
This test measures levels of Metanephrines in the blood. Metanephrines, which include Metanephrine and Normetanephrine, are the metabolites of epinephrine (adrenaline) and norepinephrine. Epinephrine and Norepinephrine are part of a group of hormones called Catecholamines which are normally produced when a person is under physical or emotional stress. Once the stress has passed the Catecholamines are normally metabolized and removed from the body through the urine in a short period of time. Levels of Catecholamines and their metabolites such as Metanephrines are normally low but they can be elevated by hormone producing tumors known as Pheochromocytomas and Paragangliomas. While these types of tumors are typically benign, the excess hormones they produce can cause hypertension, severe headaches, anxiety, sweating, nausea, rapid heartbeat and tingling in the hands and feet. If left untreated, they can result in kidney damage, heart disease and an increased risk of heart attack or stroke. Testing for Metanephrines is one of the most common ways to screen for the tumors.
This test is typically ordered when a person is experiencing unusual periods of hypertension or other symptoms common of excess Catecholamine production to help determine if a tumor is the cause of their condition. It can also be done after a tumor has been removed to monitor recovery. For people experiencing hypertension, the best time to have their blood drawn is during or immediately after an episode. Since a number of factors can cause falsely elevated Metanephrine levels and because they are eliminated from the body quickly, a blood test may not always yield accurate results. For this reason, a 24 Hour Urine Metanephrines test is often done along with the blood test or as a follow up. A Catecholamines test is often done along with a Metanephrines test or as a follow up to unusual results.
Turnaround for this test is typically 5-7 business days.
Note: Result turn around times are an estimate and are not guaranteed. Our reference lab may need additional time due to weather, holidays, confirmation/repeat testing, or equipment maintenance.
Avoid alcohol, coffee, tea, tobacco and strenuous exercise prior to collection. Overnight fasting is preferred. The person being tested should be in a supine position for at least 15 minutes before and during sample collection. A number of different medications may affect test results. Consult your physician before discontinuing any medications.