Davis's Lab & Diagnostic Tests
Homovanillic Acid and Vanillylmandelic Acid
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Synonym/Acronym:
HVA.
Rationale
To assist in diagnosis of neuroblastoma, pheochromocytoma, and ganglioblastoma and to monitor therapy.
Patient Preparation
There are no food, fluid, or activity restrictions unless by medical direction. If possible, and with medical direction, patients should withhold acetylsalicylic acid, disulfiram, pyridoxine, and reserpine for 2 days before specimen collection. Levodopa should be withheld for 2 wk before specimen collection. The test should begin between 0600 and 0800 if possible. Usually, a 24-hr urine collection is ordered. As appropriate, provide the required urine collection container and specimen collection instructions.
Normal Findings
Method: Chromatography.
| Age | Conventional Units | SI Units |
|---|---|---|
| Homovanillic Acid | (Conventional Units × 5.49) | |
| 3–6 yr | 1.4–4.3 mg/24 hr | 8–24 micromol/24 hr |
| 7–10 yr | 2.1–4.7 mg/24 hr | 12–26 micromol/24 hr |
| 11–16 yr | 2.4–8.7 mg/24 hr | 13–48 micromol/24 hr |
| Adult–older adult | 1.4–8.8 mg/24 hr | 8–48 micromol/24 hr |
| Vanillylmandelic Acid | (Conventional Units × 5.05) | |
| 3–6 yr | 1–2.6 mg/24 hr | 5–13 micromol/24 hr |
| 7–10 yr | 2–3.2 mg/24 hr | 10–16 micromol/24 hr |
| 11–16 yr | 2.3–5.2 mg/24 hr | 12–26 micromol/24 hr |
| Adult–older adult | 1.4–6.5 mg/24 hr | 7–33 micromol/24 hr |
Critical Findings and Potential Interventions
N/A
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Synonym/Acronym:
HVA.
Rationale
To assist in diagnosis of neuroblastoma, pheochromocytoma, and ganglioblastoma and to monitor therapy.
Patient Preparation
There are no food, fluid, or activity restrictions unless by medical direction. If possible, and with medical direction, patients should withhold acetylsalicylic acid, disulfiram, pyridoxine, and reserpine for 2 days before specimen collection. Levodopa should be withheld for 2 wk before specimen collection. The test should begin between 0600 and 0800 if possible. Usually, a 24-hr urine collection is ordered. As appropriate, provide the required urine collection container and specimen collection instructions.
Normal Findings
Method: Chromatography.
| Age | Conventional Units | SI Units |
|---|---|---|
| Homovanillic Acid | (Conventional Units × 5.49) | |
| 3–6 yr | 1.4–4.3 mg/24 hr | 8–24 micromol/24 hr |
| 7–10 yr | 2.1–4.7 mg/24 hr | 12–26 micromol/24 hr |
| 11–16 yr | 2.4–8.7 mg/24 hr | 13–48 micromol/24 hr |
| Adult–older adult | 1.4–8.8 mg/24 hr | 8–48 micromol/24 hr |
| Vanillylmandelic Acid | (Conventional Units × 5.05) | |
| 3–6 yr | 1–2.6 mg/24 hr | 5–13 micromol/24 hr |
| 7–10 yr | 2–3.2 mg/24 hr | 10–16 micromol/24 hr |
| 11–16 yr | 2.3–5.2 mg/24 hr | 12–26 micromol/24 hr |
| Adult–older adult | 1.4–6.5 mg/24 hr | 7–33 micromol/24 hr |
Critical Findings and Potential Interventions
N/A
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