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Homovanillic Acid (HVA), 24-Hour Urine with Creatinine
Test Code39527
Alias/See Also
LAB00192
CPT Codes
82570, 83150
Includes
CPT code 81050 may be added at an additional charge for volume measurement
Preferred Specimen
10 mL aliquot from a 24-hour urine that has been preserved with 25 mL 6N HCl, collected in a plastic 24-hour urine container
Patient Preparation
It is preferable for the patient to be off medications for three days prior to collection. However, common antihypertensives (diuretics, ACE inhibitors, calcium channel blockers, alpha and beta blockers) cause minimal or no interference. Patient should avoid alcohol, coffee, tea, tobacco and strenuous exercise prior to collection.
Minimum Volume
5 mL
Other Acceptable Specimens
Aliquot from a 24-hour urine, unpreserved with a pH ≤6, collected in a plastic 24-hour urine container
Instructions
Collect 24-hour urine with 25 mL HCl to maintain a pH ≤3. If no preservative is used, specimen must be stored refrigerated during collection but shipped frozen and pH must be ≤6.
Record 24-hour urine volume and patient's age on test request form and on urine container.
Record 24-hour urine volume and patient's age on test request form and on urine container.
Transport Container
Plastic urine container
Transport Temperature
Preserved urine: Room temperature
Unpreserved urine: Frozen
Unpreserved urine: Frozen
Specimen Stability
Preserved urine
Room temperature: 10 days
Refrigerated: 14 days
Frozen: 90 days
Upreserved urine
Room temperture: Unacceptable
Refrigerated: Unacceptable
Frozen: 30 days
Room temperature: 10 days
Refrigerated: 14 days
Frozen: 90 days
Upreserved urine
Room temperture: Unacceptable
Refrigerated: Unacceptable
Frozen: 30 days
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Preserved urine received refrigerated with pH >3 • Unpreserved urine received frozen with pH >6
Methodology
High Performance Liquid Chromatography (HPLC) • Electrochemical Detection
FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.
Setup Schedule
Tues, fri
Report Available
3-7 days
Reference Range
See Laboratory Report
Clinical Significance
Homovanillic acid (HVA, 4-hydroxy-3-methoxyphenylacetic acid) has been identified as the principal urinary metabolite of dopa and dopamine. HVA is excreted in free form in relatively large amounts, and is frequently measured to support a diagnosis of neuroblastoma and malignant pheochromocytoma. HVA has been used to monitor chronic lead exposure and response to medication, during the treatment of Parkinson's disease.
Performing Laboratory
Quest Diagnostics Nichols Institute-San Juan Capistrano, CA |
33608 Ortega Highway |
San Juan Capistrano, CA 92675-2042 |