Initial test for the diagnosis and monitoring of individuals with neuroblastoma. Should be ordered concurrently with Vanillylmandelic Acid (VMA), Urine (0080421
Quantitative High Performance Liquid Chromatography
This test is New York DOH approved.
Homovanillic acid (HVA) results are expressed as a ratio to creatinine excretion (mg/g CRT). HVA mass per day (mg/d) is not reported on specimens from patients younger than 18 years of age, for random specimens, urine collection periods other than 24 hours, or for urine volumes less than 400 mL/d. No reference interval is available for results reported in units of mg/L.
Moderately elevated HVA (homovanillic acid) may be caused by a variety of factors such as essential hypertension, intense anxiety, intense physical exercise, and numerous drug interactions (including some over-the-counter medications and herbal products).
Medications that may interfere with catecholamines and their metabolites include amphetamines and amphetamine-like compounds, appetite suppressants, bromocriptine, buspirone, caffeine, chlorpromazine, clonidine, disulfiram, diuretics (in doses sufficient to deplete sodium), epinephrine, glucagon, guanethidine, histamine, hydrazine derivatives, imipramine, levodopa (L-dopa, Sinemet®), lithium, MAO inhibitors, melatonin, methyldopa (Aldomet®), morphine, nitroglycerin, nose drops, propafenone (Rythmol), radiographic agents, rauwolfia alkaloids (Reserpine), and vasodilators. The effects of some drugs on catecholamine metabolite results may not be predictable.