Test Overview
A test for catecholamines measures the
amount of the
hormones epinephrine, norepinephrine, metanephrine, and dopamine
in the urine. These catecholamines are made by
nerve tissue, the brain, and the
adrenal glands. Catecholamines help the body respond
to stress or fright and prepare the body for "fight-or-flight"
reactions.
The
adrenal glands make large amounts of catecholamines as a reaction to stress. The
main catecholamines are epinephrine (adrenaline), norepinephrine
(noradrenaline), and dopamine. They break down into vanillylmandelic acid (VMA), metanephrine, and normetanephrine, which are passed in the urine. The amounts of VMA, metanephrine, and normetanephrine also are usually measured during a catecholamine test.
Catecholamines
increase heart rate, blood pressure, breathing rate, muscle strength, and
mental alertness. They also lower the amount of blood going to the skin and intestines and
increase blood going to the major organs, such as the brain, heart, and
kidneys.
Certain rare tumors (such as a
pheochromocytoma) can increase the amount of
catecholamines in the blood and urine. The increased amount can cause high
blood pressure, excessive sweating, headaches, fast heartbeats (palpitations),
and tremors.
Why It Is Done
A
catecholamine test is done to help diagnose a tumor in
the adrenal glands called a pheochromocytoma.
How To Prepare
You may be asked to avoid the following
foods and fluids for 2 to 3 days before having this test:
- Caffeine, such as coffee, tea, cocoa, and
chocolate
- Amines. These are found in bananas, walnuts, avocados,
fava beans, cheese, beer, and red wine.
- Any foods or fluids with
vanilla
- Licorice
- Aspirin
Do not use tobacco at all during the 24-hour urine
collection.
Be sure to keep warm during the 24-hour urine test
because being cold can increase your catecholamine levels.
Drink
plenty of fluids during the 24-hour time period to avoid
dehydration.
Many medicines may change
the results of this test. Be sure to tell your doctor about all the
nonprescription and prescription medicines you take.
Your doctor may ask you to stop certain medicines, such as blood
pressure medicines, before the test. Do not take cold or allergy remedies,
including aspirin, or nonprescription diet pills for 2 weeks before the
test.
Talk to your doctor about any concerns you have regarding
the need for the test, its risks, how it will be done, or what the results will
mean. To help you understand the importance of this test, fill out the
medical test information form(What is a PDF document?).
How It Is Done
24-hour urine sample
- You start collecting your urine in the morning.
When you first get up, empty your bladder but do not save this urine. Write
down the time that you urinated to mark the beginning of your 24-hour
collection period.
- For the next 24 hours, collect all your urine.
Your doctor or lab will usually provide you with a large container that holds
about 1 gal (4 L). The
container has a small amount of preservative in it. Urinate into a small, clean
container and then pour the urine into the large container. Do not touch the
inside of the container with your fingers.
- Keep the large container
in the refrigerator for the 24 hours.
- Empty your bladder for the
final time at or just before the end of the 24-hour period. Add this urine to
the large container and record the time.
- Do not get toilet paper,
pubic hair, stool (feces), menstrual blood, or other foreign matter in the
urine sample.
How It Feels
There is no pain while collecting a
24-hour urine sample.
Risks
There is no chance for problems while collecting
a 24-hour urine sample.
Results
A test for catecholamines measures the
amount of epinephrine, norepinephrine, and dopamine in the urine. The test also usually measures the amounts of vanillylmandelic acid (VMA), metanephrine, and normetanephrine.
Normal
The normal values listed here—called a reference range—are just a guide. These ranges vary from lab to lab, and your lab may have a different range for what's normal. Your lab report should contain the range your lab uses. Also, your doctor will evaluate your results based on your health and other factors. This means that a value that falls outside the normal values listed here may still be normal for you or your lab.
Catecholamines in a 24-hour urine sample
1
| Free catecholamines |
Less than 100
micrograms (mcg) or less than 591
nanomoles (nmol)
|
| Epinephrine |
Less than 20 mcg or less than 109
nmol
|
| Norepinephrine |
15–80 mcg or 89–473 nmol
|
| Dopamine |
65–400 mcg or 420–2612 nmol
|
| Normetanephrine |
105–354 mcg or 573–1933 nmol
|
| Metanephrine |
74–297 mcg or 375–1506
nmol
|
| Vanillylmandelic acid (VMA) |
Less than 9
milligrams (mg) or less than 45 micromoles
(mcmol)
|
Normal urine values may vary in children depending on
their age.
High values
- High levels of free catecholamines,
vanillylmandelic acid (VMA), or metanephrine can mean an adrenal gland tumor
(pheochromocytoma) or another type of tumor that makes
catecholamines is present.
- Any major stress, such as burns, a
whole-body infection (sepsis),
illness, surgery, or traumatic injury, can cause high catecholamine levels.
- Many blood pressure medicines can also cause high catecholamine
levels.
Low values
Low values may be caused by
diabetes or some
nervous system problems.
What Affects the Test
Reasons you may not be able to
have the test or why the results may not be helpful include:
- Doing physical exercise.
- Having
extreme emotional stress.
- Having surgery, injury, or
illness.
- Taking certain medicines, such as aspirin, nitroglycerin,
tricyclic antidepressants, tetracycline, theophylline, or some blood pressure
medicines.
- Using nicotine, alcohol (ethanol), or
cocaine.
- Taking nonprescription cough, cold, or sinus
medicines.
- Eating or drinking foods with caffeine.
What To Think About
- The 24-hour urine test is better for finding
high levels of catecholamines than a blood test. For more information on a
catecholamine blood test, see the topic
Catecholamines in Blood.
References
Citations
-
Fischbach FT, Dunning MB III, eds. (2009).
Manual of Laboratory and Diagnostic Tests, 8th ed.
Philadelphia: Lippincott Williams and Wilkins.
Other Works Consulted
- Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis:
Saunders.
- Fischbach FT, Dunning MB III, eds. (2009).
Manual of Laboratory and Diagnostic Tests, 8th ed.
Philadelphia: Lippincott Williams and Wilkins.
- Pagana KD, Pagana TJ (2010). Mosby’s Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
Credits
|
By
|
Healthwise Staff |
|
Primary Medical Reviewer
|
E. Gregory Thompson, MD - Internal Medicine |
|
Specialist Medical Reviewer
|
Alan C. Dalkin, MD - Endocrinology |
|
Last Revised
|
June 20, 2012 |