|Test Code||VMAUR / VMA-M|
|Test||VANILLYLMANDELIC ACID (VMA), 24 HOUR URINE|
|Methodology||Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)|
|Description||This test (vanillylmandelic acid [VMA]), along with homovanillic acid, is useful for screening children for catecholamine-secreting tumors.
Supporting a diagnosis of neuroblastoma
Monitoring neuroblastoma treatment
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:
Metanephrines, Fractionated, Free, Plasma (METPL / 81609M)
|Specimen||5.2 mL from a 24-hour urine collection. Add 25 mL of 50% acetic acid as preservative at the start of collection. If specimen is collected refrigerated, preservative may be added up to 4 hours after collection. Use 15 mL of 50% acetic acid for children <5 years old. This preservative is intended to achieve a pH of between approximately 1 and 5. If necessary, adjust urine pH to 1 to 5 with 50% acetic or HCl acid. See "Urine Preservatives" in Special Instructions for multiple collections.
Note: 1. Administration of L-dopa may falsely increase VMA results; it should be discontinued 24 hours prior to and during collection of specimen.
2. PATIENT'S AGE AND 24HR VOLUME IS REQUIRED ON REQUEST FORM FOR PROCESSING.
3. Follow "Urine Collection" instructions.
4. For children 14 years of age and younger, Vanillylmandelic Acid (VMA) and Homovanillic Acid, (HVA), Pediatric, Urine (9254M) is the recommended test.
|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
> or =15 years (adults): <8.0 mg/24 hours
|Analytic Time||2 Days|
|Day(s) Test Set Up||Monday through Saturday|