|Downtime form:||A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery|
All four tests may be done on same collection.
Absolute Minimum: 1 mL from a well-mixed 24 hr urine collection.
Abstain from medications for 72 hours prior to collection.
Components Age Ref. Interval Homovanilla Acid 18 years and older 0.0-15.0 mg/d per 24 hr Homovanillic Acid The HVA-to-creatinine ratio will be Ratio to CRT reported when the patient is under 18 years, the urine collection is random or other than 24 hours, or the urine volume is less than 400 mL/24 hours. Homovanillic Acid 0-2 years 0-42 mg/g CRT Ratio to CRT 3-5 years 0-22 mg/g CRT 6-17 years 0-15 mg/g CRT 18 years and older 0-8 mg/g CRT Creatinine, Urine per 24 hr Male 3-8 years 140-700 mg/d 9-12 years 300-1300 mg/d 13-17 years 500-2300 mg/d 18-50 years 1000-2500 mg/d 51-80 years 800-2100 mg/d 81 years and older 600-2000 mg/d Female 3-8 years 140-700 mg/d 9-12 years 300-1300 mg/d 13-17 years 400-1600 mg/d 18-50 years 700-1600 mg/d 51-80 years 500-1400 mg/d 81 years and older 400-1300 mg/d
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.
Urine Tests Requiring Preservatives, Refrigeration or Special Containers