Catecholamine, Endocrine Study, Plasma
Use
This test is useful for the diagnosis of pheochromocytoma and paraganglioma by measuring plasma catecholamines in specimens collected from individuals in both supine and standing positions as an auxiliary to fractionated plasma and urine metanephrine measurements. It assists in diagnosing and following up on patients with neuroblastoma and related tumors and evaluating patients with autonomic dysfunction/failure or autonomic neuropathy.
Special Instructions
The test is not the first-tier test for pheochromocytoma, as plasma catecholamine levels may not be continuously elevated. It is recommended to discontinue drugs that affect catecholamine release or metabolism at least one week prior to testing. Also, the patient must refrain from eating, using tobacco, or consuming caffeinated beverages for at least 4 hours before specimen collection.
Limitations
This test should not be used as the first-line test for pheochromocytoma due to non-continuous elevation of plasma catecholamine levels. Specificity at high sensitivity cut-off levels is not good for separating tumor patients from non-tumor patients with similar symptoms. Variability in results due to environmental factors like stress, noise, body position, and consumption of caffeine or nicotine should be minimized.
New York Approved
Methodology
Mass Spectrometry (LC-MS/MS)
Biomarkers
LOINC Codes
- 95056-8
- 1601-4
- 1465-4
- 95053-5
- 17368-2
- 95054-3
- 95055-0
Result Turnaround Time
2-9 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
3 mL plasma per collection
Minimum Volume
2 mL per collection
Container
Preferred: 10-mL Catecholamine tubes containing EDTA-sodium metabisulfite solution; Acceptable: 6-mL Catecholamine tubes containing EDTA-sodium metabisulfite solution
Collection Instructions
Drawing from a catheter is required. Have the patient rest for 30 minutes in a supine position before drawing. Obtain blood into chilled EDTA-sodium metabisulfite tube, centrifuge in refrigerated centrifuge, aliquot plasma into a plastic vial, and freeze immediately.
Patient Preparation
The patient must not eat, use tobacco, or drink caffeinated beverages for at least 4 hours before specimen collection. Discontinue relevant drugs at least 1 week before the test.
Storage Instructions
Specimens must remain at refrigerated temperature at all times. Transport frozen.
Causes for Rejection
Gross hemolysis is acceptable. Ensure specimen handling conditions are maintained to prevent oxidation and inaccurate results.
Stability Requirements
| Temperature | Period |
|---|---|
| Frozen | 28 days |