Nor Metanephrines-Free

Normetanephrine is one of the breakdown products, or metabolites, of norepinephrine, which is a neurotransmitter and hormone present in the body. It is primarily responsible for increasing the heart rate and blood pumping from the heart. Thereby, playing a defining role in the body’s “fight or flight” response.

Norepinephrine is one of the catecholamine compounds, a group of substances released into the blood during physical or emotional stress. Usually, these are produced by the adrenal glands or by the cells of the nervous system. The various functions of catecholamines are as follows:

• Transmitting nerve impulses in the brain
• Dilating the bronchioles (small air passages present in the lung)
• Dilating the pupils
• Constricting blood vessels to increase blood pressure
• Increasing the heart rate
• Boosting the rate at which the body uses energy

Since catecholamine compounds only fulfil a specific purpose, they are broken down into inactive compounds. In the case of norepinephrine, it is turned into normetanephrine and vanillylmandelic acid (VMA), which are then expelled in the form of urine.

However, certain tumours in the adrenal gland (pheochromocytoma) and outside the adrenal gland (paraganglioma) may cause large amounts of catecholamine compounds to be released, along with their metabolites. Due to this, large concentrations of these elements can be found in the blood.

The normetanephrines-free test is used to detect the presence of these compounds in the blood. Hence, it helps in the determination of tumours. Since the usual normetanephrine levels in the plasma are low, a high count indicates the likelihood of an adrenal tumour.

Due to the composition of normetanephrine in both the blood and urine, this test may require both of these samples. The procedure for the normetanephrines-free blood test is standard, with the clinical lab technician drawing blood from the vein in the arm. The sample is then stored carefully in a labelled container and sent for analysis. The doctor usually recommends a blood test during specific symptoms. These are:

• Persistent hypertension
• A sudden burst of hypertension (paroxysm)

On the other hand, the normetanephrines-free urine test requires a 24-hour urine sample for analysis. Usually, the lab provides a labelled container, which has to be filled with urine in a 24-hour period.

Usually, the lab technician will ask that the sample be refrigerated and provide a preservative along with it so that the results are accurate.

Apollo 24|7 offers the normetanephrines-free test to ensure that the tumours can be caught early.

Some of the symptoms that may require seeking medical attention for adrenal gland tumours are:

• Severe headaches
• Rapid heart rate (especially without engaging in any physical activity or stress)
• Tremor
• Constant sweating
• Flushing

A doctor might better help understand these symptoms and, if necessary, recommend a normetanephrines-free urine test to gauge the reason. 

Frequently asked questions

Why is it important to get a normetanephrines-free test?

Usually, adrenal gland tumours, pheochromocytoma, and paraganglioma are rare. Even when they occur, most are benign and do not spread to other parts initially. However, they might turn cancerous if left untreated for a long time, and the symptoms might get worse. A normetanephrines-free test helps detect these tumours quickly and work out an effective treatment plan.

What do the results of the normetanephrines-free test signify?

The usual range of normetanephrine in the plasma or urine is low. So, if the test results are positive, these compounds are present in more than usual quantities. On the other hand, a negative result signals normal levels.

What could be the potential reasons for adrenal tumours?

More often than not, adrenal gland tumours are caused due to your environment and lifestyle. Some of these reasons may include smoking, living a sedentary lifestyle, and being exposed to certain cancer-causing substances like radiation. Additionally, genetic defects also play a role.

What are some things to remember before the normetanephrines-free test?

Since the test targets normetanephrine, a compound released due to physical or emotional stress, it is vital to avoid vigorous exercises before the test. Also, talk to your doctor to ensure that no existing medicine interferes with the results of the normetanephrines-free test.

What if your normetanephrines-free test results are too low?

If you are getting tested for adrenal gland tumours, it is improbable that your normetanephrines-free test results are too low. This is because low levels are observed only during the treatment of pheochromocytoma, which involves the intake of metyrosine.

Can you have multiple adrenal tumours in your body?

Yes, multiple tumours can arise in the body, even in the adrenal glands. Typically, a single tumour may form. However, if you have a family history of pheochromocytomas, you may encounter a tumour in each adrenal gland.