VANILMANDELIC ACID, RANDOM UR

Code
900.5600
Name
VANILMANDELIC ACID, RANDOM UR
Category
None
Department
Send-Out
Start Date
Expiration Date
Synonyms
VMA
CPT Codes
84585, 82570
Site
SBMF
Reference Test
29260
ATLAS Test Code

Specimen Information

Type

Urine, Random

Volume

10.0 ml

Transport Info

Acidify urine sample with 6N Hydrochloric Acid to pH between 1.0 and 3.0 when received in lab (Approx. 1.0 mL of 6 N HCl for every 100.0 mL of urine)
Refrigerated

Fasting Required?
False
Patient Instructions

Routine random urine collection
IMPORTANT: Refrigerate after collection and through transportation to prevent bacterial growth
Note: 24-hour urine is optimal specimen for testing, refer to Vanilmandelic Acid (VMA), 24-Hour Urine

Reference Range

0.0-6.0 mg/g creatinine

Methodology

High Performance Liquid Chromatography (HPLC)

Clinical Significance

Diagnosis and follow-up of patients with pheochromocytoma and related neurogenic tumors
Quantitation of the acidic metabolites of catecholamines has been valuable in the diagnosis and follow-up of patients with pheochromocytoma and related neurogenic tumors. It has been found that approximately one in every 500 hypertensive patients may have this type of tumor. Vanilmandelic acid (VMA) or 4-hydroxy-3-methoxymandelic acid (HMMA) is the end product of both epinephrine (adrenaline) and norepinephrine (noradrenaline) metabolism. Measurement of urinary VMA is commonly used as a diagnostic tool because VMA is present in larger amounts than other catechol metabolites and it is stable in acidified solutions. Since catecholamine-secreting tumors are surgically curable, patients with clinical features that suggest adrenergic excess, particularly those with severe hypertension and patients from families with history of multiple endocrine neoplasia syndromes should be tested. Urinary VMA measurements can be used to screen for pheochromocytoma, but they are considered less sensitive although more specific than urinary metanephrine measurements. It is also used to follow patients with neuroblastoma.

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