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Test ID: CATU    
Catecholamine Fractionation, Free, 24 Hour, Urine

Specimen Type Describes the specimen type needed for testing

Urine

Specimen Required Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.

Container/Tube: Plastic, 10-mL urine tube (Supply T068)

Specimen Volume: 2 mL

Collection Instructions:

1. Collect urine for 24 hours.

2. Add 25 mL of 50% acetic acid as preservative at start of collection. Use 15 mL of 50% acetic acid for children <5 years old. This preservative is intended to achieve a pH of between approximately 2 and 4.

3. This assay is of greatest value when the specimen is collected during a hypertensive episode.

4. Discontinue any epinephrine, norepinephrine, or dopamine injections/infusions at least 12 hours before specimen collection, unless drug monitoring is the goal.

5. Discontinue drugs that release or hinder metabolism of epinephrine, norepinephrine, or dopamine for at least 1 week before obtaining the specimen (see Cautions for details). If this is not possible for medical reasons, contact the laboratory to discuss whether a shorter drug-withdrawal period may be acceptable.

6. Do not perform the test on patients withdrawing from legal or illegal drugs known to cause rebound plasma catecholamine release during withdrawal (see Cautions for details).

Additional Information:

1. 24-Hour volume is required.

2. See Urine Preservatives in Special Instructions for multiple collections.

Forms: If not ordering electronically, submit a General Request Form (Supply T239) with the specimen.

 

Urine Preservative Collection Options

Ambient

No

Refrigerated

Yes

Frozen

Yes

6N HCl

Yes

50% Acetic Acid

Preferred

Na2CO3

No

Toluene

No

6N HNO3

Yes

Boric Acid

Yes

Thymol

Yes

Specimen Minimum Volume Defines the amount of specimen required to perform an assay once, including instrument and container dead space. Submitting the minimum specimen volume makes it impossible to repeat the test or perform confirmatory or perform reflex testing. In some situations, a minimum specimen volume may result in a QNS (quantity not sufficient) result, requiring a second specimen to be collected.

1.5 mL

Reject Due To Identifies specimen types and conditions that may cause the specimen to be rejected

Hemolysis

NA

Lipemia

NA

Icterus

NA

Other

NA

Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.

Specimen TypeTemperatureTime
UrineRefrigerated (preferred)7 days
 Frozen 14 days
 Ambient 7 days