Vanillylmandelic Acid (VMA), Random Urine (VMAR)

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Test Code: VMARSO

Overview
Ordering
Specimen
Performing
Clinical/Interpretive
Contacts
Coding

Synonyms/Keywords

3-Methoxy-4-Hydroxymandelic Acid
4-Hydroxy-3-Methoxymandelic Acid
Neuroblastoma Profile
Vanillylmandelic Acid
VMA

Vanillylmandelic Acid Rnd-VMAR

Vanillylmandelic Acid, Random, Urine

U VMARSO

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

Specimen Requirements

Fasting Required	Specimen Type	Preferred Container/Tube	Acceptable Container/Tube	Specimen Volume	Specimen Minimum Volume (allows for 1 repeat)	Pediatric Minimum Volume (no repeat)
No	Urine	Urine Plastic Container		5 mL	2 mL

Collection Processing Instructions

NOTE:

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 tests are ordered.

Bactrim may interfere with detection of the analyte. All patients taking Bactrim should be identified to the laboratory when VMA tests are ordered.

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 (Special Chemistry department staff will adjust pH prior to sending to Mayo)

pH. (Special Chemistry department staff will adjust pH prior to sending to Mayo)

Additional Information:

Patient's age is required.

Specimen Stability Information

Specimen Type	Temperature	Time
Urine	Refrigerate (preferred)	28 days
Urine	Frozen	180 days

Interference

Values are more commonly elevated during a hypertensive episode. Values may be normal in some individuals with a pheochromocytoma.

Performing Laboratory Information

Performing Location	Day(s) Test Performed	Report Available	Methodology/Instrumentation
Mayo Clinic Laboratories	Monday through Friday	3-5 days	Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

Reference Lab

Mayo Clinic Laboratories

Test 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 Range Information

Performing Location	Reference Range
Mayo Clinic Laboratories	<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): <7.0 mg/g creatinine

Interpretation

Vanillylmandelic acid (VMA) and/or homovanillic acid 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 VMA values are suggestive of a pheochromocytoma, but they are not diagnostic.

Outreach CPTs

CPT	Modifier (if needed)	Quantity	Description	Comments
84585		1

Classification