Catecholamine Fractionation, Supine, Plasma, Free
Use
This test is useful for the diagnosis of pheochromocytoma and paraganglioma when collected from individuals in a supine position. It serves as an auxiliary test to fractionated plasma and urine metanephrine measurements. Additionally, it aids in the diagnosis and follow-up of patients with neuroblastoma and related tumors as an auxiliary test to urine vanillylmandelic acid and homovanillic acid measurements. It is also beneficial for evaluating patients with autonomic dysfunction/failure or autonomic neuropathy.
Special Instructions
This test is only orderable as part of a profile. For more information, refer to CATPA / Catecholamine, Endocrine Study, Plasma. Patient preparation involves discontinuing drugs that affect catecholamine levels before specimen collection, avoiding food, tobacco, and caffeine for at least 4 hours prior.
Limitations
Plasma catecholamine levels can vary due to changes in posture, stress, and other physiological conditions. Accurate results depend on proper specimen collection and handling due to the labile nature of catecholamines. Medications and conditions affecting catecholamine levels should be managed appropriately. The specificity of diagnostic cutoffs for pheochromocytoma is not reliable for differentiating similar symptoms in tumor patients.
New York Approved
Methodology
Mass Spectrometry (LC-MS/MS)
Biomarkers
LOINC Codes
- 95056-8
- 1601-4
- 1465-4
- 95053-5
Result Turnaround Time
2-9 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
3 mL
Minimum Volume
2 mL
Container
Plastic vial
Collection Instructions
Collection requires the use of chilled EDTA-sodium metabisulfite 10-mL tubes. After the patient rests supine for 30 minutes, draw the specimen through an indwelling intravenous catheter, discard initial 3 mL of blood, and immediately chill and centrifuge. Freeze aliquot plasma within 30 minutes.
Patient Preparation
Discontinue catecholamine-related drugs one week prior, and avoid food, tobacco, and caffeine for at least 4 hours before collection.
Storage Instructions
Keep the specimen refrigerated and then freeze immediately after centrifugation.
Causes for Rejection
Gross hemolysis, lipemia, or icterus
Stability Requirements
| Temperature | Period |
|---|---|
| Frozen | 28 days |