Vanillylmandelic Acid (VMA), 24 Hour, Urine
NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.
Screening children for catecholamine-secreting tumors
Supporting a diagnosis of neuroblastoma
Monitoring patients with a treated neuroblastoma
Special Instructions and Forms Describes specimen collection and preparation information, test algorithms, and other information pertinent to test. Also includes pertinent information and consent forms to be used when requesting a particular test
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
Vanillylmandelic Acid, 24 Hr, U
Specimen Type Describes the specimen type needed for testing
Specimen Required Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.
Container/Tube: Plastic, 10-mL urine tube (Supply T068)
Specimen Volume: 5.2 mL
1. Collect a 24-hour urine specimen.
2. Add 25 mL of 50% acetic acid as preservative at the start of collection. If specimen is refrigerated during collection, preservative may be added up to 4 hours after collection. Use 15 mL of 50% acetic acid for children <5 years old. This preservative is intended to achieve a pH of between approximately 1 and 5. If necessary, adjust urine pH to 1 to 5 with 50% acetic or HCl acid.
1. Patient's age and 24-hour volume are required.
2. Administration of L-dopa may falsely increase vanillylmandelic acid results; it should be discontinued 24 hours prior to and during collection of specimen.
3. See Urine Preservatives in Special Instructions for multiple collections.
Urine Preservative Collection Options
50% Acetic Acid
Yes* (pH must be <5)
*If boric acid is used, note on specimen container. Also, verify that pH is in desired range (pH=1-5). If pH is outside of desired range, adjust pH with a stronger acid (acetic acid is preferred but other acids listed above could be used if available) in a dropwise fashion to bring pH into desired range.
Specimen Minimum Volume Defines the amount of specimen required to perform an assay once, including instrument and container dead space. Submitting the minimum specimen volume makes it impossible to repeat the test or perform confirmatory or perform reflex testing. In some situations, a minimum specimen volume may result in a QNS (quantity not sufficient) result, requiring a second specimen to be collected.
Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.
|Urine||Refrigerated (preferred)||7 days|
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: <27.0 mg/g creatinine
1 year: <18.0 mg/g creatinine
2-4 years: <13.0 mg/g creatinine
5-9 years: <8.5 mg/g creatinine
10-14 years: <7.0 mg/g creatinine
> or =15 years (adults): <8.0 mg/24 hours
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
Administration of L-dopa may falsely increase 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 homovanillic acid tests are ordered.
Values are more commonly elevated during a hypertensive episode.
Values may be normal in some individuals with pheochromocytoma.
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/81609 Metanephrines, Fractionated, Free, Plasma
-METAF/83006 Metanephrines, Fractionated, 24 Hour, Urine
-CATU/9276 Catecholamine Fractionation, Free, Urine
Clinical Reference 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 Diseases. Edited by N Blau, M Duran, ME Blaskovics. London, UK, Chapman and Hall Medical, 1996, pp 79-98
2. Gitlow SE, Bertrani LM, Rausen A, et al: Diagnosis of neuroblastoma by qualitative and quantitative determination of catecholamine metabolites in urine. Cancer 1970;25(6):1377-1383
3. Pacak K, Linehan M, Elsenhofer G, et al: Recent advances in genetics, diagnosis, localization, and treatment of pheochromocytoma. Ann Internl Med 2001;134(4):315-329
4. Strenger V, Kerbl R, Dornbusch HJ, et al: Diagnostic and prognostic impact of urinary catecholamines in neuroblastoma patients. Pediatr Blood Cancer 2007;48:504-509
Method Description Describes how the test is performed and provides a method-specific reference
Hydrophilic-lipophilic balance (HLB) solid-phase extraction (SPE) is performed on an aliquot of urine from a 24-hour collection. The SPE column is eluted with 1 mL of methanol. The eluate is evaporated at 50 degrees C under nitrogen, and the residue reconstituted in 1 mL of the liquid chromatography-tandem mass spectrometry (LC-MS/MS) mobile phase. LC-MS/MS is performed by injecting 10 mcL of the reconstituted specimen onto an amide-C16 HPLC column. The mobile phase (15% methanol in 0.05% aqueous formic acid) is pumped over the HPLC analytical column at a rate of 1.0 mL/min with the flow diverted to the MS/MS electrospray probe tip by 1:5. Vanillylmandelic acid (VMA) elutes apart from the bulk of the specimen matrix at a retention time of approximately 1.5 minutes. VMA is quantitated using a stable isotope labeled internal standard from calibration over a concentration range 1.03 to 20 mg/L.(Magera MJ, Thompson AL, Stoor AL, et al: Determination of vanillylmandelic acid in urine by stable isotope dilution and electrospray tandem mass spectrometry. Clin Chem 2003;49:825-826)
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday through Saturday; 8 a.m.
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
2 days (not reported on Sunday)
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location The location of the laboratory that performs the test
Test Classification Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer's instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR), Investigation Use Only (IUO) product, or a Research Use Only (RUO) product.
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.
CPT Code Information Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Medical Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
LOINC® Code Information Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the result codes returned for this test or profile.
|Result ID||Reporting Name||LOINC Code|
|3581||VMA, Child (<15yr)||30571-4|