Test Code LAB2355 Vanillylmandelic Acid, 24 Hour, Urine
Reporting Name
Vanillylmandelic Acid, 24 Hr, USCH Clinical System Name: Vanillylmandelic Acid 24 Hour Urine
Useful For
Screening children for catecholamine-secreting tumors using a 24-hour urine collection when requesting testing for vanillylmandelic acidonly
Supporting a diagnosis of neuroblastoma
Monitoring patients with a treated neuroblastoma
Ordering Guidance
In the past, this test has been used to screen for pheochromocytoma. However, vanillylmandelic acid (VMA) is not the analyte of choice to rule out a diagnosis of pheochromocytoma. Recommended tests for that purpose include:
-PMET / Metanephrines, Fractionated, Free, Plasma
-METAF / Metanephrines, Fractionated, 24 Hour, Urine
-CATU / Catecholamine Fractionation, Free, 24 Hour, Urine
Necessary Information
1. Patients age is required.
2. Collection duration (in hours) and urine volume (in milliliters) are required.
3. All patients receiving L-dopa should be identified to the laboratory when this test is ordered.
4. Bactrim may interfere with detection of the analyte. All patients taking Bactrim should be identified to the laboratory when this test is ordered.
Specimen Required
Patient Preparation: Administration of L-dopa may falsely-increase vanillylmandelic acid results; it should be discontinued 24 hours prior to and during specimen collection.
Supplies: Urine Tubes, 10 mL (T068)
Collection Container/Tube: Clean, plastic urine collection container
Submission Container/Tube: Plastic, 10-mL urine tube
Specimen Volume: 5 mL
Collection Instructions:
1. 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 12 hours after collection. Use 15 mL of 50% acetic acid for children younger than 5 years. This preservative is intended to achieve a pH of between approximately 1 and 5.
2. Collect a 24-hour urine specimen.
3. If necessary, adjust urine pH to a level between 1 and 5 by adding 50% acetic acid or hydrochloric acid dropwise and checking the pH.
Additional Information: For multiple collections see Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens.
Specimen Type
UrineSpecimen Minimum Volume
2 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Urine | Refrigerated (preferred) | 28 days | |
Frozen | 180 days |
Day(s) Performed
Monday through Friday
TAT: 4 - 6 days
Performing Laboratory
Mayo Clinic Laboratories in RochesterMethod Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Method Description
Vanillylmandelic acid (VMA) is measured by solid-phase extraction (SPE) of a 1-mL aliquot of urine. A known amount of stable-isotope labeled VMA internal standard (IS) is added to each urine specimen prior to SPE. VMA and IS are eluted from the SPE column with methanol. The methanol is evaporated and the VMA and IS are redissolved in liquid chromatography tandem mass spectrometry mobile phase. A portion of this prepared extract is injected onto a LC column that separates VMA and IS from the bulk of any remaining specimen matrix. The VMA and IS are measured by tandem-mass spectrometry using the selected reaction monitoring mode. VMA is quantified using the ratio to IS versus urine calibrators.(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; Eisenhofer G, Grebe S, Cheung NV. Monoamine-producing tumors. In Rifai N, Horvath AR, Wittwer CT, eds. Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. 6th ed. Elsevier; 2018:chap 63)
Reference Values
<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
≥15 years (adults): <8.0 mg/24 hours
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
84585
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
VMA | Vanillylmandelic Acid, 24 Hr, U | 43099-1 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
3580 | Vanillylmandelic Acid, Adult (>14y) | 3122-9 |
3581 | Vanillylmandelic Acid, Child (<15y) | 30571-4 |
TM41 | Collection Duration | 13362-9 |
VL39 | Urine Volume | 3167-4 |
Special Instructions
Report Available
3 to 5 daysReject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Forms
If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen.
Aliases: 3-Methoxy-4-Hydroxymandelic Acid, 4-Hydroxy-3-Methoxymandelic Acid, VMA