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What is normetanephrine plasma?

What is normetanephrine plasma?

The plasma free metanephrines test is used to help diagnose or rule out the presence of a rare tumor called a pheochromocytoma or a paraganglioma (PPGL) that releases excess metanephrines. Testing also may be used when a tumor has been treated or removed to monitor for recurrence.

How long does a plasma Metanephrine test take?

How long does the test take? The test will last between 30 and 60 minutes. You will be asked to lie down for approximately 30 minutes, then a blood sample will be taken by an endocrine nurse specialist and sent to an external lab to be tested. There is usually a wait of three to four weeks for the test results.

What is a high Normetanephrine level?

Higher levels of metanephrines may mean that you have an adrenal gland tumor. But false-positive results can happen. Higher levels may also be caused by obstructive sleep apnea, stress, or other illnesses.

What causes high plasma metanephrines?

Are there any patients with normal plasma normetanephrine levels?

One patient with von Hippel–Lindau disease had a normal plasma normetanephrine concentration; this patient had a very small adrenal tumor (<1 cm). The high sensitivity of measurements of plasma normetanephrine and metanephrine was accompanied by a high level of specificity (96 percent).

What should the metanephrine level be in pheochromocytoma?

In most pheochromocytoma patients, metanephrine and normetanephrine levels are elevated > 4-fold the normal range. Normetanephrine and metanephrine levels are often mildly elevated in patients with essential hypertension.

What do you need to know about the metanephrine test?

Metanephrine, plasma free, fractionated plasma free metanephrines What is this test? This test measures the substances metanephrine and normetanephrine in your blood. It helps find out if you have a tumor of the adrenal glands called pheochromocytoma. The adrenal glands sit on top of your kidneys.

What causes high levels of norepinephrine and normetanephrine?

Normetanephrine is a metabolite of norepinephrine. Normally, the levels of Normetanephrine are low in the plasma. However, when there are tumors in the body that originate from neural crest cells called paragangliomas or neuroblastomas, or from pheochromocytomas (an adrenal gland tumor), the levels of Normetanephrine rise significantly.

One patient with von Hippel–Lindau disease had a normal plasma normetanephrine concentration; this patient had a very small adrenal tumor (<1 cm). The high sensitivity of measurements of plasma normetanephrine and metanephrine was accompanied by a high level of specificity (96 percent).

Normetanephrine is a metabolite of norepinephrine. Normally, the levels of Normetanephrine are low in the plasma. However, when there are tumors in the body that originate from neural crest cells called paragangliomas or neuroblastomas, or from pheochromocytomas (an adrenal gland tumor), the levels of Normetanephrine rise significantly.

What are plasma metanephrine levels in paraganglioma patients?

Interpretation In the normal population, plasma metanephrine and normetanephrine levels are low, but in patients with pheochromocytoma or paragangliomas, the concentrations may be significantly elevated.

When to test for elevated plasma free metanephrines?

Due to the low prevalence of pheochromocytomas and related tumors (<1:100,000), it is recommended to confirm elevated plasma free metanephrines with a second, different testing strategy in order to avoid large numbers of false-positive test results.