Vanillylmandelic Acid, 24-hour Urine-13489
Test info
VMA
VMA, 24-hour urine
Diagnose pheochromocytoma.
VMA is of value for evaluation of hypertension, diagnose and follow up neuroblastoma, ganglioneuroma, and ganglioneuroblastoma.
Most neuroblastoma patients excrete excess HVA in 24-hour collections. If VMA and HVA are both used in work-up, up to 80% of all cases will be detected.
Specimen
Patient should avoid salicylates, caffeine, phenothiazine, and antihypertension agents, as well as coffee, tea, chocolate, fruit (especially bananas and any vanilla containing substances) for 72 hours prior to collection.
(Note: This volume does not allow for repeat testing.)
- Measure and record total urine volume.
- Mix well
- Transfer a 4mL aliquot to a Transfer vial/tube with cap - 12mL (LabCorp)
- Label the aliquot tube with thepatient's name, date and time collection started, and date and time collection completed.
Transfer vial/tube with cap - 12mL (LabCorp)
24 hr urine collection container with Acetic acid
24 hr urine collection container with HCl
CAUTION: Strong acid; may cause skin burns.
Ambient (preferred) - 7 days
Refrigerated - 14 days
Frozen - 14 days
Freeze/thaw cycles - stable x3
Performance
Liquid chromatography/tandem mass spectrometry (LC/MS-MS)
Clinical and Interpretive info
0.0 - 7.5 mg/24 hours