Vanillylmandelic Acid
Label Mnemonic: VMA24
Epic Lab Code: LAB7449
Downtime Form: A-1a General Laboratory Requisition
Commercial Mail-out Laboratory
5231 RCP
356-8593
Specimen(s):
24 hr Urine More information
Specimen Instructions:
Refrigerate during 24 hr collection in plastic container. Refrigeration is the preferred method of preservation. Collection containers available from pharmacy.

All four tests may be done on same collection.

Abstain from medications for 72 hours prior to collection.
Collection Medium:
Urine - 24 hour/timed plastic urine container
Minimum:
Preferred Minimum: 4 mL from a well-mixed 24 hr urine collection. Random urine is also accepted at reference lab. Refrigerate during collection and submission.

Absolute Minimum: 1 mL from a well-mixed 24 hr urine collection. Random urine is also accepted at reference lab. Refrigerate during collection and submission.
Turn Around Time:
1-4 days upon receipt at reference laboratory
Reference Range:
Components Age Ref. Interval Vanillylmandelic 18 years and older 0.0-7.0 mg/d Acid - per 24 hr Vanillylmandelic The VMA-to-creatinine ratio will be reported when Acid - Ratio the patient is under 18 years or the urine volume to CRT is less than 400 mL/24 hours. Vanillylmandelic 0-2 years 0-27 mg/g CRT Acid - Ratio 3-5 years 0-13 mg/g CRT to CRT 6-17 years 0-9 mg/g CRT 18 years and older 0-6 mg/g CRT Creatinine Urine - 24 hr Male 3-8 years 140-700 mg/d 9-12 years 300-1300 mg/d 13-17 years 500-2300 mg/d 18-50 years 1000-2500 mg/d 51-80 years 800-2100 mg/d 81 years and older 600-2000 mg/d Female 3-8 years 140-700 mg/d 9-12 years 300-1300 mg/d 13-17 years 400-1600 mg/d 18-50 years 700-1600 mg/d 51-80 years 500-1400 mg/d 81 years and older 400-1300 mg/d
Interpretive Data:
Vanillylmandelic acid (VMA) results are expressed as a ratio to creatinine excretion (mg/g cr). VMA mass per day (mg/d) is not reported on specimens from patients younger than 18 years of age, for random specimens, urine collection periods other than 24 hours, or for urine volumes less than 400 mL/d. No reference interval is available for results reported in units of mg/L.
Comments:
If screening for Neuroblastoma, the following tests are suggested: CAT24 (Catecholamines, Fractionated; Dopamine is included), HVA24 (Homovanillic Acid), MET24 (Metanephrines), VMA24 (Vanillylmandelic Acid). VMA, Catecholamines, HVA, and Metanephrines may be done on same collection. All five tests may be done on same collection. Moderately elevated VMA (vanillylmandelic acid) can be caused by a variety of factors such as essential hypertension, intense anxiety, intense physical exercise, and numerous drug interactions (including some over-the-counter medications and herbal products). Medications that may interfere with catecholamines and their metabolites include amphetamines and amphetamine-like compounds, appetite suppressants, bromocriptine, buspirone, caffeine, chlorpromazine, clonidine, disulfiram, diuretics (in doses sufficient to deplete sodium), epinephrine, glucagon, guanethidine, histamine, hydrazine derivatives, imipramine, levodopa (L-dopa, Sinemet®), lithium, MAO inhibitors, melatonin, methyldopa (Aldomet®), morphine, nitroglycerin, nose drops, propafenone (Rythmol), radiographic agents, rauwolfia alkaloids (Reserpine), tricyclic antidepressants, and vasodilators. The effects of some drugs on catecholamine metabolite results may not be predictable.
Methodology:
Quantitative High Performance Liquid Chromatography - Tandem Mass Spectrometry
CPT Code:
84585
 
See also:
Catecholamines, Fractionated, 24 hr Urine
Homovanillic Acid, 24 hr Urine
Metanephrines Total, 24 hr Urine