Catecholamines, Fractionated

Label Mnemonic:	CATUR
Epic code:	LAB7405
Downtime form:	Doctor/Provider Orders - Pathology Core and Specialty Care Nursery

Commercial Mailout Laboratory
6240-8 RCP
356-8593

Specimen(s):

Random Urine

Collection Medium:

Yellow top round bottom tube (no additive)

Minimum:

Preferred Minimum: 4 mL random urine
Absolute Minimum: 2.5 mL random urine

Record total volume and collection time interval on transport tube and test request form.

Abstain from medications for 72 hours prior to collection.

Rejection Criteria:

Specimens preserved with boric acid or acetic acid. Specimens with pH greater than 7.

Turn Around Time:

1-5 days upon receipt at reference laboratory

Reference Range:

Reference Intervals for Ratio-to-Creatinine (CRT) 
Calculations (Random Urine)

Components      Age                 Ref. Interval

Dopamine        0-11 months         240-1290 μg/g crt
                1-3 years           80-1220 μg/g crt
                4-10 years          220-720 μg/g crt
                11-17 years         120-450 μg/g crt
                18 years and older  0-250 μg/g crt

Epinephrine     0-11 months         0-380 μg/g crt
                1-3 years           0-82 μg/g crt
                4-10 years          5-93 μg/g crt
                11-17 years         3-58 μg/g crt
                18 years and older  0-20 μg/g crt

Norepinephrine  0-11 months         25-310 μg/g crt
                1-3 years           25-290 μg/g crt
                4-10 years          27-110 μg/g crt
                11-17 years         4-105 μg/g crt
                18 years and older  0-45 μg/g crt

Interpretive Data:

The optimal specimen for this testing is a 24-hour urine collection. Mass per day calculations are not reported for patients younger than 18 years of age and for the following specimen types: a random collection, a collection with duration of less than 20 hours, a collection with duration of greater than 28 hours, or a collection with total volume less than 400 mL. Ratios to creatinine may be useful for these evaluations.

Smaller increases in catecholamine concentrations (less than two times the upper limit) usually are the result of physiological stimuli, drugs, or improper specimen collection. Significant elevation of one or more catecholamines (three or more times the upper reference limit) is associated with an increased probability of a neuroendocrine tumor.

Comments:

Secreting neuroendocrine tumors are typically associated with catecholamine concentrations several times higher than the upper reference intervals. Large elevations can be seen in life-threatening illnesses and drug interferences. Common reasons for slight and moderate elevations include intense physical activity, emotional and physical stress, drug interferences, and improper specimen collection.

Medications which may physiologically interfere with catecholamines and metabolites include amphetamines and amphetamine-like compounds, appetite suppressants, bromocriptine, buspirone, caffeine, carbidopa- levodopa (Sinemet®), clonidine, dexamethasone, diuretics (in doses sufficient to deplete sodium), ethanol, isoproterenol, methyldopa (Aldomet®), MAO inhibitors, nicotine, nose drops, propafenone (Rythmol), reserpine, theophylline, tricyclic antidepressants, and vasodilators. The effects of some drugs on catecholamine results may not be predictable.

Dopamine testing within this determination.

Methodology:

Quantitative High Performance Liquid Chromatography-Tandem Mass Spectrometry

CPT Code:

82384

See also:
Homovanillic Acid, Random Urine
Metanephrines Total, Random Urine
Vanillylmandelic Acid, Random Urine

See Additional Information:
Urine Tests Requiring no Preservatives