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Catecholamines - urineDefinitionThis is a test that measures the level of catecholamines or catecholamine metabolites (break-down products) in the urine. Alternative NamesDopamine-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 PerformedFor this test, you must urinate into a special bag or container every time you use the bathroom for 24-hour period.
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 TestA 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:
Drugs that can decrease catecholamine measurements include:
How the Test Will FeelThe test involves only normal urination, and there is no discomfort. Why the Test is PerformedThe 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:
Normal Results
Note: mg/hour = milligrams per hour; mcg/hour = micrograms per hour. What Abnormal Results MeanElevated levels of urinary catecholamines may indicate:
RisksThere are no risks. ConsiderationsThe 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"). ReferencesThe 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. The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997-
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