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Epic Test Code LAB401 Homovanillic Acid, 24 Hour, Urine

Additional Codes

MML Code: HVA

LIS Code: HVAU

NY State Approved

Yes

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Reporting Name

Homovanillic Acid (HVA), 24 Hr, U

Method Name

Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)

Specimen Stability Information

Specimen Type Temperature Time Special Container
Urine Refrigerated (preferred) 28 days
  Frozen  180 days


Necessary Information


1. Collection duration and urine volume in milliliters are required.

2. Patient's age is required.

3. All patients receiving L-dopa should be identified to the laboratory when this test is ordered.

4. Bactrim may interfere with detection of the analyte. All patients taking Bactrim should be identified to the laboratory when this test is ordered.



Specimen Required


Patient Preparation: Administration of L-dopa may falsely increase homovanillic acid results; it should be discontinued 24 hours prior to and during specimen collection.

Supplies: Urine Tubes, 10 mL (T068)

Container/Tube: Plastic, 10-mL urine tube

Specimen Volume: 5 mL

Collection Instructions:

1. Add 25 mL of 50% acetic acid as preservative at start of collection. If specimen is refrigerated during collection, preservative may be added up to 12 hours after collection. Use 15 mL of 50% acetic acid for children younger than 5 years. This preservative is intended to achieve a pH of between approximately 1 and 5.

2. Collect a 24-hour urine specimen.

3. If necessary, adjust urine pH to a level between 1 and 5 by adding 50% acetic acid or hydrochloric acid dropwise and checking the pH.

Additional Information:

1. The sensitivity of this test is greater on a 24-hour specimen than on a random specimen.

2. See Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens for multiple collections.


Specimen Type

Urine

Specimen Minimum Volume

2 mL

Reference Values

<1 year: <35.0 mg/g creatinine

1 year: <30.0 mg/g creatinine

2-4 years: <25.0 mg/g creatinine

5-9 years: <15.0 mg/g creatinine

10-14 years: <9.0 mg/g creatinine

≥15 years (adults): <8.0 mg/24 hours

Report Available

2 to 4 days

Day(s) Performed

Monday through Friday

CPT Code Information

83150

Reject Due To

  All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

Useful For

Screening children for catecholamine-secreting tumors using a 24-hour urine collection when requesting homovanillic acid only

 

Monitoring neuroblastoma treatment

 

Screening patients with possible inborn errors of catecholamine metabolism

Interpretation

Vanillylmandelic acid (VMA) and/or homovanillic acid (HVA) concentrations are elevated in over 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 values are suggestive of a deficiency of dopamine beta-hydrolase, a neuroblastoma, a pheochromocytoma, or may reflect administration of L-dopa.

 

Decreased urinary HVA values may suggest monoamine oxidase-A deficiency.

Cautions

Administration of L-dopa may falsely increase homovanillic acid (HVA) results. Patients receiving L-dopa should stop taking it for 24 hours before and during the collection.

 

All patients receiving L-dopa should be identified to the laboratory when vanillylmandelic acid (VMA) and HVA tests are ordered.

 

All patients taking Bactrim should be identified to the laboratory when VMA and HVA tests are ordered due to potential interference.

Specimen Retention Time

7 days

Disease States

  • Neuroblastoma

Urine Preservative Collection Options

Note: For preservative or application of temperature controls timing, see Specimen Required.

Ambient (No additive)

No

Refrigerate (No additive)

No

Frozen (No additive)

No

50% Acetic Acid

Preferred

Boric Acid

No

Diazolidinyl Urea

No

6M Hydrochloric Acid

OK

6M Nitric Acid

OK

Sodium Carbonate

No

Thymol

No

Toluene

No

Forms

If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen.