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    Catecholamines - urine

    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 Results

    • 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:

    1. acute anxiety
    2. ganglioblastoma (very rare)
    3. ganglioneuroma (very rare)
    4. neuroblastoma (rare)
    5. pheochromocytoma (rare)
    6. severe stress
    Additional conditions under which the test may be performed:

    Risks

    There are no risks.

    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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