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HelpTest ID VMAR Vanillylmandelic Acid (VMA), Random, Urine
Useful For
Screening children for catecholamine-secreting tumors with a random urine collection when requesting vanillylmandelic acid only
Supporting a diagnosis of neuroblastoma
Monitoring patients with a treated neuroblastoma
Method Name
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Reporting Name
Vanillylmandelic Acid, Random, USpecimen Type
UrineContainer/Tube: Plastic, 10-mL urine tube (T068)
Specimen Volume: 5 mL
Collection Instructions:
1. Collect a random urine specimen.
2. Adjust the random urine pH to a level between 1 and 5 by adding 50% acetic acid dropwise and checking the pH.
Additional Information:
1. Patient's age is 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.
Forms: If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:
Neurology Test Request Form-General (T732) (http://www.mayomedicallaboratories.com/it-mmfiles/neurology-request-form.pdf)
Oncology Test Request Form (T729) (http://www.mayomedicallaboratories.com/it-mmfiles/oncology-request-form.pdf)
Specimen Minimum Volume
2 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Urine | Refrigerated (preferred) | 7 days |
| Frozen | 7 days |
Clinical Information
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 one of the above-mentioned tumors.
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): <7.0 mg/g creatinine
Cautions
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 (HVA) tests are ordered.
Values are more commonly elevated during a hypertensive episode.
Values may be normal in some individuals with a pheochromocytoma.
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
Day(s) Performed
Monday through Friday; 8 a.m.
Report Available
2 days (not reported on Sundays)Performing Laboratory
Mayo Medical Laboratories in Rochester
Test Classification
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
84585