Catecholamines, Fractionated, 24-Hour Urine with Creatinine
Also known as: Adrenaline, Epinephrine, Noradrenaline, Catecholamines, Free
Use
The three catecholamines (norepinephrine, epinephrine and dopamine) are the principal secretory products of neural tissue. Clinically, the measurement of circulating catecholamines is valuable in the diagnosis of catecholamine secreting tumors associated chiefly with hypertension (pheochromocytomas, neuroblastomas and gangliomas) and with the evaluation of orthostatic hypotension.
Special Instructions
Record 24‑hour urine volume and patient's age on test request form and urine container. Ideal collection uses a 10 mL aliquot from a preserved 24‑hour urine; if unpreserved, ensure pH ≤ 6 and ship frozen.
Limitations
Recent surgery, traumatic injury, upright posture, cold, anxiety, pain, clonidine withdrawal, and concurrent acute or chronic illness may produce elevated results.
Methodology
Other
Biomarkers
Result Turnaround Time
4-6 days
Related Documents
For more information, please review the documents below
Specimen
Urine
Volume
10 mL aliquot from a 24‑hour urine
Minimum Volume
5 mL
Container
plastic, 24‑hour urine container
Collection Instructions
Collect 24‑hour urine with 25 mL of 6N HCl to maintain a pH ≤ 3; if no preservative used, must be stored refrigerated during collection but shipped frozen and pH must be ≤ 6.
Patient Preparation
It is preferable for the patient to be off medications for three days prior to collection; common antihypertensives cause minimal or no interference. Avoid alcohol, coffee, tea, tobacco and strenuous exercise prior to collection.
Storage Instructions
Preserved urine: ship at room temperature; unpreserved: ship frozen.
Causes for Rejection
Preserved urine received refrigerated with pH >3; unpreserved urine received frozen with pH >6
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 7 days (preserved) |
| Refrigerated | 30 days (preserved) |
| Frozen | 49 days (preserved); 30 days (unpreserved) |