TEST CATALOG ORDERING & RESULTS SPECIMEN HANDLING CUSTOMER SERVICE EDUCATION & INSIGHTS
Test Catalog

Test ID: VMA    
Vanillylmandelic Acid, 24 Hour, Urine

Useful For Suggests clinical disorders or settings where the test may be helpful

Screening children for catecholamine-secreting tumors with a 24-hour urine collection when requesting testing for only vanillylmandelic acid

 

Supporting a diagnosis of neuroblastoma

 

Monitoring patients with a treated neuroblastoma

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Vanillylmandelic acid (VMA) and other catecholamine metabolites (homovanillic acid: HVA and dopamine) are typically elevated in patients with catecholamine-secreting tumors (eg, neuroblastoma, pheochromocytoma, and other neural crest tumors). VMA and HVA levels may also be useful in monitoring patients who have been treated as a result of 1 of the above-mentioned tumors.

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 (adults): <8.0 mg/24 hours

Interpretation Provides information to assist in interpretation of the test results

Vanillylmandelic acid and/or homovanillic acid concentrations are elevated in most patients (more than 90%) 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 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

Values are more commonly elevated during a hypertensive episode.

 

Values may be normal in some individuals with pheochromocytoma.

 

All patients taking Bactrim should be identified to the laboratory when VMA and HVA tests are ordered due to potential interference.

Clinical Reference Recommendations for in-depth reading of a clinical nature

1. Hyland K: Disorders of neurotransmitter metabolism. In: Blau N, Duran M, Blaskovics ME, Gibson KM, eds. Physician’s Guide to the Laboratory Diagnosis of Metabolic Diseases. Springer; 2003:107-122. doi: 10.1007/978-3-642-55878-8_8

2. Gitlow SE, Bertrani LM, Rausen A, Gribetz D, Dziedzic SW: Diagnosis of neuroblastoma by qualitative and quantitative determination of catecholamine metabolites in urine. Cancer. 1970 Jun;25(6):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 Jun;47(9):848-852

5. Matthay KK, Maris JM, Schleiermacher G, et al: Neuroblastoma. Nat Rev Dis Primers. 2016 Nov 10;2:16078. doi: 10.1038/nrdp.2016.78

Special Instructions Library of PDFs including pertinent information and forms related to the test