Laboratory: Clinical Biochemistry  (METABOLIC)
Test Name:
HOMOVANILLIC ACID (HVA) - (U)
Test Code: HVA
Clinical Information:
Alternate Name(s): HVA (Homovanillic Acid)
Description: Homovanillic acid (HVA) and vanillylmandelic acid (VMA)  are the preferred test for screening for neuroblastoma in a random urine specimen. Both tests should be performed.
Supporting neuroblastoma diagnosis & monitoring patients with a treated neuroblastoma.
Test Indications: Homovanillic acid (HVA) and vanillylmandelic acid (VMA) concentrations are elevated in more than 90% of patients with neuroblastoma; both tests should be performed. A positive test could be due to a genetic or nongenetic condition. Additional confirmatory testing is required.
A normal result does not exclude the presence of a catecholamine-secreting tumor.
Elevated HVA and VMA values are suggestive of a pheochromocytoma, but they are not diagnostic. For investigation of PHEOCHROMOCYTOMA in adults, the test FRACTIONATED METANEPHRINES (urine) should be ordered only. 
This test is available on random or 24 h urine collection.
Recommendations: All patients receiving L-dopa should be identified to the laboratory when this test is ordered.
Patient preparation instructions: Administration of L-dopa may falsely increase homovanillic acid and vanillylmandelic acid results; it should be discontinued 24 hours prior to and during collection of the specimen.
Collection Devices:
Specimen Required:

Adult: Volume 5-10 mL
Pediatric: Volume minimum 1.0 mL
Collection Information: 
JA110-50-01B Random Urine Processing Flow Chart
JA110-50-01A 24 Hour Urine Processing Flow Chart
Specimen Stability: 
Ambient: Acidified – 7 days
Refrigerated: Acidified – 4 weeks
Frozen:  Acidified or not acidified – 6 months
- Samples MUST BE either Acidified OR Frozen within 4 hours of collection by the Collecting Site. Otherwise, the sample will be rejected.
- After acidifying, record pH on the requisition for registration (recording in clinical details in Delphic)
- If only frozen, record the pH before freezing.
Referral:

Shipping & Storage:
- Samples MUST BE either Acidified OR Frozen within 4 hours of collection by the Collecting Site. Otherwise, the sample will be rejected
- After acidifying, record pH on the requisition for registration (recording in clinical details in Delphic)
- If only frozen, record the pH before freezing.
- Store and ship accordingly.
- Submit aliquoted sample (24h urine collection)
Testing Laboratory (MB): Metabolic Lab (HSC)
If you have any questions, call Metabolic Lab at (204) 787-4530
Requisition:
Reference Values:
AGE HVA VMA
(Years) (µmol/mmol creat.) (µmol/mmol creat.)
<1 ≤ 21.7 ≤ 14.3
1 ≤ 18.6 ≤ 12.9
2–4 ≤15.5 ≤ 9.1
5-9 ≤ 9.3 ≤ 6.9
10-14 ≤ 5.6 ≤ 4.6
>14 ≤ 6.2 ≤ 4.0
Method of Analysis: Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Availability:
Within 10 Days
For urgent analysis, please communicate with the Metabolic Lab (204)787-4530 for arrangement.
See Also:
More Information: