Vanillylmandelic Acid (VMA) and Homovanillic Acid (HVA), Random, Urine
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Elevated values of homovanillic acid (HVA), vanillylmandelic acid (VMA), and other catecholamine metabolites (eg, dopamine) may be suggestive of the presence of a catecholamine-secreting tumor (eg, neuroblastoma, pheochromocytoma, or other neural crest tumors). HVA and VMA levels may also be useful in monitoring patients who have been treated as a result of the above-mentioned tumors. HVA levels may also be altered in disorders of catecholamine metabolism: monamine oxidase-A deficiency can cause decreased urinary HVA values, while a deficiency of dopamine beta-hydrolase (the enzyme that converts dopamine to norepinephrine) can cause elevated urinary HVA values.
First preferred test for screening for catecholamine-secreting tumors in a random urine specimen when requesting both homovanillic acid and vanillylmandelic acid
Supporting a diagnosis of neuroblastoma
Monitoring patients with a treated neuroblastoma
Homovanillic acid (HVA) and vanillylmandelic acid (VMA) concentrations are elevated in more than 90% of patients with neuroblastoma; both tests should be performed. A positive test could be due to a genetic or nongenetic condition. Additional confirmatory testing is required.
A normal result does not exclude the presence of a catecholamine-secreting tumor.
Elevated HVA and VMA values are suggestive of a pheochromocytoma, but they are not diagnostic.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Administration of L-dopa may falsely increase homovanillic acid (HVA)/vanillylmandelic acid (VMA) results. Patients receiving L-dopa should stop taking it for 24 hours before and during the collection.
All patients receiving L-dopa should be identified to the laboratory when VMA and HVA tests are ordered.
Bactrim may interfere with detection of the analyte. All patients taking Bactrim should be identified to the laboratory when VMA and HVA tests are ordered.
In the past, this test has been used to screen for pheochromocytoma. However, VMA is not the analyte of choice to rule out a diagnosis of pheochromocytoma. Recommended tests for this purpose are:
-PMET / Metanephrines, Fractionated, Free, Plasma
-METAF / Metanephrines, Fractionated, 24 Hour, Urine
-CATU / Catecholamine Fractionation, Free, 24 Hour, Urine
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
<1 year: <25.0 mg/g creatinine
1 year: <22.5 mg/g creatinine
2-4 years: <16.0 mg/g creatinine
5-9 years: <12.0 mg/g creatinine
10-14 years: <8.0 mg/g creatinine
> or =15 years: <7.0 mg/g creatinine
<1 year: <35.0 mg/g creatinine
1 year: <30.0 mg/g creatinine
2-4 years: <25.0 mg/g creatinine
5-9 years: <15.0 mg/g creatinine
10-14 years: <9.0 mg/g creatinine
> or =15 years: <8.0 mg/g creatinine
Clinical References Provides recommendations for further in-depth reading of a clinical nature
1. Hyland K, Biaggioni I, Elpeleg ON, et al: Disorders of neurotransmitter metabolism. In Physician's Guide to the Laboratory Diagnosis of Metabolic Disease. Edited by N Blau, M Duran, M E Blaskovics.London UK, Chapman and Hall Medical, 1996, pp 79-98
2. Gitlow SE, Bertani LM, Rausen A, et al: Diagnosis of neuroblastoma by qualitative and quantitative determination of catecholamine metabolites in urine. Cancer 1970;25:1377-1383
3. Strenger V, Kerbl R, Dornbusch HJ, et al: Diagnostic and prognostic impact of urinary catecholamines in neuroblastoma patients. Pediatr Blood Cancer 2007 May;48(5):504-509
4. Barco S, Gennai I, Reggiardo G, et al: Urinary homovanillic and vanillylmandelic acid in the diagnosis of neuroblastoma: report from the Italian Cooperative Group for Neuroblastoma. Clin Biochem 2014 June;47(9):848-852