Catecholamine Fractionation, Urinary, Free (Sendout)
General Information
- Lab Name
- Catecholamine Fract, Free, URN
- Lab Code
- RUFCAT
- Epic Ordering
- Catecholamine Fractionation, Free, Urine (Sendout)
- External Test Id
- CATU
- Description
***Unless this test is ordered in conjunction with 24-h urine metanephrines (RUFMET), requests for this test should be discussed with the Lab Medicine resident on-call (206) 598-6190.*** Either plasma free metanephrines Metanephrines, Fractionated, Free, Plasma [RPLMET] or 24-h urine metanephrines Metanephrines, Fractionated, 24-Hour, Urine (Sendout) [RUFMET] offer superior performance for diagnosis of pheochromocytoma. The most sensitive test is plasma free metanephrines Metanephrines, Fractionated, Free, Plasma [RPLMET]; the most specific test is 24-h urine metanephrines Metanephrines, Fractionated, 24-Hour, Urine (Sendout) [RUFMET].
- Note: Resident approval is expected for orders from within the teaching environment of UW Medicine (includes UW-MT, HMC, UWNC) but is not expected for outside clients of the reference laboratory, nor for physicians on the "Preauthorized Physicians" list.
Ordering Notes:
- This assay is of greatest value when the specimen is collected during a hypertensive episode.
- Discontinue any epinephrine, norepinephrine or dopamine injections/infusions at least 12 hours before specimen collection, unless drug monitoring is the goal*.
- Discontinue drugs that release or hinder metabolism of epinephrine, norepinephrine, or dopamine for at least 1 week before obtaining the specimen*.
- Do not perform the test on patients withdrawing from legal or illegal drugs known to cause rebound plasma catecholamine release during withdrawal.
- *For advice on assessing the risk of removing patients from these medications and alternatives, consider consultation with a specialist in endocrinology or hypertension.
- References
For a recent review of the biochemical diagnosis of pheochromocytoma, see Pacak K et al. Nature Clin Pract Endocrinol Metab 2007; 3:92-102.PMID: 17237836.
- Synonyms
- Adrenaline-Urine, CATU, Dopamine-Urine, Epinephrine-Urine, Noradrenaline-Urine, Norepinephrine-Urine, Pressor Amines-Urine
- Components
-
Code Name RUCATI Catecholamine Interval, URN RUCATV Catecholamine Total Volume,URN RUNEPI Norepinephrine, URN RUEPI Epinephrine, URN RUDOPA Dopamine, URN
Interpretation
- Method
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
- Reference Range
- See individual components
- References
For a recent review of the biochemical diagnosis of pheochromocytoma, see Pacak K et al. Nature Clin Pract Endocrinol Metab 2007; 3:92-102.PMID: 17237836.
Ordering & Collection
- Specimen Type
- Urine
- Collection
-
24 Hour Urine:
- Add 25 mL of 50% Acetic Acid as preservative in 24-hour urine container at the start of collection. This preservative is intended to achieve a pH of between approximately 2 and 4. Use 15 mL of 50% acetic acid for children less than 5 years old.
- Although 50% Acetic Acid is preferred, may also be collected with 6M HCL, 6M HNO(3), or Boric Acid. Urine without preservative refrigerated during collection is also acceptable for testing. Refer to: Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens.
- Collect urine for 24 hours. Record the start date/time and end date/time on the requisition or on the collection container. Samples with collection intervals less than 22 hours or greater than 26 hours will be rejected by Mayo.
Unacceptable: Random urine, or urine with collection intervals <22 hrs or >26 hrs.
- Add 25 mL of 50% Acetic Acid as preservative in 24-hour urine container at the start of collection. This preservative is intended to achieve a pH of between approximately 2 and 4. Use 15 mL of 50% acetic acid for children less than 5 years old.
- Approval Required
- LMR Approval required for orders from within the university system if not ordered concurrently with 24-hr urine metanephrines (RUFMET).
- Handling Instructions
Outside Laboratories:
- Mix urine. Measure the total volume and record it on the requisition.
- Ensure that the pH falls within between approximately 2 and 4.
- Transfer 10 mL urine to a screw-capped plastic vial and refrigerate.
Stability: Refrigerated (preferred): 7 days; Frozen: 14 days; Ambient: 7 days.
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability. Random urine samples or timed collections <22 hours or >26 hours are not acceptable for testing.
- Quantity
-
requested: 10 mL urine
minimum: 2 mL urine
Processing
- Processing
- Mix urine. Measure the total volume and record it on the requisition.
- Check that the pH falls within between approximately 2 and 4.
- Transfer 10 mL urine to a screw-capped plastic vial and refrigerate.
Sendouts, order Mayo Test: CATU.
Stability: Refrigerated (preferred): 7 days; Frozen: 14 days; Ambient: 7 days.All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.
Performance
- LIS Dept Code
- Sendouts Mayo Lab (RF) (MARF)
- Performing Location(s)
-
Sendout Mayo Clinic Laboratories (Superior Drive)
800-533-17103050 Superior Drive NW
Rochester, MN 55901 - Frequency
- Performed: Monday - Saturday. Report Available: 2-4 days.
- Available STAT?
- No
Billing & Coding
- CPT codes
- 82384
- LOINC
- 11133-6
- Interfaced Order Code
- UOW1811