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Catecholamines in Urine
Test Overview
A test for catecholamines measures the amount of the hormones
epinephrine, norepinephrine, metanephrine, and dopamine in the blood. 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)
and metanephrine, which are passed in the urine.
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 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. This causes 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 health professional may ask you to stop certain medicines,
such as blood pressure medicines, before the test. Do not take cold or allergy
remedies, including aspirin, and 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.
Normal
Normal values may vary widely from lab to lab.
Catecholamines in a 24-hour urine
sample
| Free catecholamines |
Less than 100
micrograms (µg) or less than 590
nanomoles (nmol)
|
| Epinephrine |
Less than 20 µg or less than 109 nmol
|
| Norepinephrine |
Less than 100 µg or less than 590 nmol
|
| Dopamine |
65–400 µg or 384–2360 nmol
|
| Vanillylmandelic acid (VMA) |
Less than 6.8
milligrams (mg) or less than 35 micromole
(µmol)
|
| Metanephrine |
Less than 1.3 mg or less than 6.7 µmol
|
| Normetanephrine |
15–80 µg or 89–473 nmol
|
Normal urine values may vary in children depending on their
age.
High values
- High levels of catecholamines,
vanillylmandelic acid (VMA), or metanephrine can mean an adrenal gland tumor
(pheochromocytoma) or another type of tumor that makes
catecholamines is present.
- High levels may also be seen with any
major stress, such as burns, a whole-body infection (sepsis),
illness, surgery, or traumatic injury.
- 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, and 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 medical test
Catecholamines in Blood.
References
Other Works Consulted
-
Chernecky CC, Berger BJ, eds. (2004). Laboratory Tests and Diagnostic Procedures, 4th ed.
Philadelphia: Saunders.
-
Fischbach FT, Dunning MB III, eds. (2004).
Manual of Laboratory and Diagnostic Tests, 7th ed.
Philadelphia: Lippincott Williams and Wilkins.
-
Pagana KD, Pagana TJ (2006). Mosby’s
Manual of Diagnostic and Laboratory Tests, 3rd ed. St. Louis:
Mosby.
Credits
| Author | Jan Nissl, RN, BS |
| Editor | Susan Van Houten, RN, BSN, MBA |
| Associate Editor | Tracy Landauer |
| Primary Medical Reviewer | Caroline S. Rhoads, MD - Internal Medicine |
| Specialist Medical Reviewer | Alan C. Dalkin, MD - Endocrinology |
| Last Updated | August 21, 2006 |
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| Author: | Jan Nissl, RN, BS | Last Updated: August 21, 2006 |
| Medical Review: | Caroline S. Rhoads, MD - Internal Medicine
Alan C. Dalkin, MD - Endocrinology |
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