Sign in →

Order Code LABVH Vanillylmandelic Acid and Homovanillic Acid, Random, Urine

Reporting Name

VMA and HVA, Random, U

Useful For

Preferred first test for screening for catecholamine-secreting tumors in a random urine specimen when requesting both homovanillic acid and vanillylmandelic acid

 

Supporting a diagnosis of neuroblastoma

 

Monitoring patients with a treated neuroblastoma

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Specimen Type

Urine


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. Patient's age is required.

2. All patients receiving L-dopa should be identified to the laboratory when this test is ordered.

3. 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 homovanillic acid and vanillylmandelic acid results; it should be discontinued 24 hours prior to 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. Collect a random urine specimen.

2. Adjust the urine pH to a level between 1 and 5 by adding 50% acetic acid or hydrochloric acid dropwise and checking the pH.


Specimen Minimum Volume

2 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Urine Refrigerated (preferred) 28 days
  Frozen  180 days

Reference Values

VANILLYLMANDELIC ACID

<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: <7.0 mg/g creatinine

 

HOMOVANILIC ACID

<1 year: <35.0 mg/g creatinine

1 year: <30.0 mg/g creatinine

2-4 years: <25.0 mg/g creatinine

5-9 years: <15.0 mg/g creatinine

10-14 years: <9.0 mg/g creatinine

≥15 years: <8.0 mg/g creatinine

Day(s) Performed

Monday through Friday

CPT Code Information

83150-HVA

84585-VMA

Method Description

Homovanillic Acid:

Homovanillic acid (HVA) is measured by solid-phase extraction (SPE) of a 1-mL aliquot of urine. A known amount of stable isotope-labeled HVA internal standard (IS) is added to each urine specimen prior to SPE. HVA and IS are eluted from the SPE column with methanol. The methanol is evaporated and the HVA and IS are redissolved in liquid chromatography tandem-mass spectrometry (LC-MS/MS) mobile phase. A portion of this prepared extract is injected onto a LC column that separates HVA and IS from the bulk of any remaining specimen matrix. The HVA and IS are measured by mass spectrometry/tandem-mass spectrometry using the selected reaction monitoring mode. HVA is quantified using the ratio to IS versus urine calibrators.(Magera MJ, Stoor A, Helgeson JK, Matern D, Rinaldo P. Determination of homovanillic acid in urine by stable isotope dilution and electrospray tandem mass spectrometry. Clin Chim Acta. 2001;306[1-2]:35-41; 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)

 

Vanillylmandelic Acid:

Vanillylmandelic acid (VMA) is measured by SPE of a 1-mL aliquot of urine. A known amount of stable isotope-labeled VMA 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 LC-MS/MS 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 MS/MS 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)

Reject Due To

  All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

Method Name

Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)

Forms

If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen.