Patient Education - Endocrine Encyclopedia
Endocrine Surgery Encyclopedia
 Definition:
This is a test that measures the level of catecholamines or catecholamine metabolites
(break-down products) in the urine.
Alternative Names:
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 into the toilet 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).
The infant should be checked frequently and the bag changed 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. Extra collection bags may be necessary.
When finished, label and return the container as instructed.
Catecholamines can be also be measured with a blood sample.
How to prepare for the test:
A health care provider will tell you whether or not to discontinue any drugs or activities
that may interfere with the test.
Certain foods can increase urinary catecholamines, including coffee, tea, bananas, chocolate,
cocoa, citrus fruits, and vanilla. Avoid these for several days prior to the test.
Acute stress and vigorous exercise may also affect the test results.
The following drugs can increase catecholamine measurements:
- caffeine
- acetominophen (Tylenol)
- levodopa
- lithium
- aminophylline
- chloral hydrate
- clonidine
- disulfiram
- erythromycin
- insulin
- methenamine
- methyldopa
- nicotinic acid (large doses)
- quinidine
- tetracyclines
- nitroglycerin
Drugs that can decrease catecholamine measurements include:
- clonidine
- disulfiram
- guanethidine
- imipramine
- MAO inhibitors
- phenothiazines
- salicylates
- reserpine
How the test will feel:
The test involves only normal urination, and there is no discomfort.
Why the test is performed:
The test is primarily used to diagnose pheochromocytoma and neuroblastoma, and to monitor
the effectiveness of their treatments. Urine catecholamine levels are elevated in the majority
of neuroblastoma cases.
Catecholamines are small, chemically similar molecules derived from the amino acid tyrosine.
The major catecholamines are dopamine, norepinephrine, and epinephrine (old name: adrenalin).
All of the catecholamines are broken down by their target tissues (such as the brain)
or by the liver and become inactive substances that appear in the urine:
- dopamine becomes Homovanillic acid (HVA)
- norepinephrine becomes normetanephrine and Vanillylmandelic acid (VMA)
- epinephrine becomes metanephrine and VMA
Normal Values:
- VMA: 2 to 7 mg/24-hours
- epinephrine: 0.5 to 20 mcg/24-hours
- norepinephrine: 15 to 80 mcg/24-hours
- dopamine: 65 to 400 mcg/24-hours
- metanephrine: 24 to 96 mcg/24-hours (some laboratories give the range as 140 to 785
mcg/24-hours)
- normetanephrine: 75 to 375 mcg/24-hours
- total urine catecholamines: 14 to 110 mcg/24-hours
Note: mg/hour = milligrams per hour; mcg/hour = micrograms per hour.
What abnormal results mean:
Elevated levels of urinary catecholamines may indicate:
- acute anxiety
- ganglioblastoma (very rare)
- ganglioneuroma (very rare)
- neuroblastoma (rare)
- pheochromocytoma (rare)
- severe stress
Additional conditions under which the test may be performed:
- multiple endocrine neoplasia
(MEN) II
What the risks are:
There are no risks.
Special considerations:
The accuracy of the test can be affected by several foods and drugs as well as physical activity
and stress (See "How to prepare for the test").
References:
The Neuroblastoma Hope Foundation. Diagnostic Criteria.Available at: http://www.acor.org/nbl/diagnost.htm.
Accessed May 17, 2005.
Wilson SP, Kamin DL, Feldman JM. Acetaminophen administration interferes with urinary
metanephrine (and catecholamine) determinations. Clin Chem. 1985;31(6):1093-4.
Review Date: 5/17/2005
Reviewed By: Nikheel S. Kolatkar, MD, Clinical and Research Fellow, Division of Endocrinology,
Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston,
MA. Review provided by VeriMed Healthcare Network.
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