Catecholamines - urineDefinition:
Catecholamines are small molecules made by nerve tissue (including the brain) and the adrenal gland.
The major catecholamines are dopamine , norepinephrine , and epinephrine. These substances break down into other compounds, which leave your body through your urine.
A urine test can be done to measure the level of catecholamines in your body.
Catecholamines can also be measured with a blood test. See also: Catecholamines - blood
Dopamine-urine test; Epinephrine-urine test; Adrenalin-urine test; Vanillylmandelic acid (VMA); Urine metanephrine; Normetanephrine; Norepinephrine-urine test; Urine catecholamines; VMA; HVA; Metanephrine; Homovanillic acid (HVA)
How the test is performed:
For this test, you must urinate into a special bag or container every time you use the bathroom for 24-hour period.
- On day 1, urinate over the toilet into the container or bag when you wake up in the morning. Close the container tightly. Keep it in the refrigerator or a cool place during the collection period.
- Urinate into the special container every time you use the bathroom for the next 24 hours.
- On day 2, urinate into the container in the morning again when you wake up.
- Label the container with your name, the date, the time of completion, and return it as instructed.
For an infant:
Thoroughly wash the area around the urethra (the hole where urine flows out). Open a urine collection bag (a plastic bag with an adhesive paper on one end).
- For males, place the entire penis in the bag and attach the adhesive to the skin.
- For females, place the bag over the two folds of skin on either side of the vagina (labia). Put a diaper on the baby (over the bag).
Check the infant frequently, and change the bag after the infant has urinated. Empty the urine from the bag into the container provided by your doctor.
Because lively infants can cause the bag to move, this procedure may take a couple of attempts. You may need extra collection bags.
When finished, label the container and return it as instructed.
How to prepare for the test:
Acute stress and vigorous exercise may affect the test results.
Foods that can increase urinary catecholamines include coffee, tea, bananas, chocolate, cocoa, citrus fruits, and vanilla. Avoid these foods for several days prior to the test.
Certain drugs can also affect test results. Your health care provider may tell you to stop taking certain medicines before the test. Never stop taking medicine without first talking to your doctor.
The following drugs can increase catecholamine measurements:
- Acetaminophen (Tylenol)
- Chloral hydrate
Nicotinic acid (large doses)
Drugs that can decrease catecholamine measurements include:
- MAO inhibitors
How the test will feel:
The test involves only normal urination, and there is no discomfort.
Why the test is performed:
The test is usually done to diagnose an adrenal gland tumor called pheochromocytoma . It may also be used to diagnose neuroblastoma . Urine catecholamine levels are increased in most persons with neuroblastoma.
The urine test for catecholamines may also be used to monitor those who are receiving treatment for these conditions.
All of the catecholamines are broken down into inactive substances that appear in the urine:
- Dopamine becomes Homovanillic acid (HVA)
- Norepinephrine becomes normetanephrine and vanillylmandelic acid (VMA)
- Epinephrine becomes metanephrine and VMA
The following normal values represent the amount of the substance found in the urine over a 24 hour period. Normal values vary from lab to lab, but in general are as follows:
- Dopamine: 65 - 400 micrograms (mcg)/24 hours
- Epinephrine: 0.5 - 20 mcg/24 hours
- Metanephrine: 24 - 96 mcg/24 hours (some laboratories give the range as 140 - 785 mcg/24-hours)
- Norepinephrine: 15 - 80 mcg/24 hours
- Normetanephrine: 75 - 375 mcg/24 hours
- Total urine catecholamines: 14 - 110 mcg/24 hours
- VMA: 2 - 7 milligrams (mg)/24 hours
What abnormal results mean:
Elevated levels of urinary catecholamines may indicate:
Additional conditions under which the test may be performed:
What the risks are:
There are no risks.
Several foods and drugs, as well as physical activity and stress, can affect the accuracy of this test.
Young WF. Adrenal medulla, catecholamines, and pheochromocytoma. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 246.