CATECHOLAMINES, FRACTIONATED, PLASMA

General Information

HLAB/HOL Code: CATP
UPHSM LIS Test #: 6050
Schedule:
Testing Time:
Testing Lab: Labcorp

Specimen Info
Only 1 specimen type required, unless otherwise specified

Volume: 3 (2.2) mL
Temperature: Frozen
Tube Type: Lavender-top (EDTA) tube or Green-top (heparin) tube
Collection Info:
Specimen: Plasma, frozen

Volume: 3 mL (plasma)

Minimum Volume: 2.2 mL (plasma)

Container: Lavender-top (EDTA) tube or green-top (heparin) tube

Collection: Draw blood in lavender-top (EDTA) tube or green-top (heparin) tube. Invert to mix with preservatives. Centrifuge and transfer the plasma to labeled plastic transport tube. Freeze immediately (within one hour after collection) at -20°C and ship frozen. The time between blood collection and the preparation of plasma is quite critical; if the time exceeds one hour, catecholamine values increase (when blood is kept at 4°C) or decrease (when left at 20°C). To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested.

Patient Preparation: Patient should be fasting for four or more hours without smoking. Walnuts, bananas, and α-methyldopa (Aldomet®) should be avoided for a week prior to sampling. Other drug interference may occur, including epinephrine and epinephrine-like drugs (eg, nosedrops, sinus and cough preparations, bronchodilators, appetite suppressants). Test is unreliable in subjects on levodopa or methenamine mandelate. Avoid patient stress. See Limitations. An indwelling heparinized venous catheter is advocated, since venipuncture can cause an increase in the substances for which testing is being done. Patient should remain supine in quiet surroundings for at least 30 minutes.

Causes for Rejection: Specimen not drawn in correct tube; plasma not received frozen; thawed specimen; inadequate patient preparation

Specimen Acceptability

Plasma, frozen

Methods

High-pressure liquid chromatography (HPLC) with electrochemical (EC) detection

Clinical Utilities

Diagnose pheochromocytoma and those paragangliomas which may secrete epinephrine, norepinephrine, or both. Such tumors may cause paroxysmal or persistent hypertension. Investigation of hypertensive patients, especially younger individuals, particularly when hypertension is paroxysmal, suggesting pheochromocytoma. Plasma catecholamines with urinary metanephrines and VMA are a recommended test battery for pheochromocytoma. Others recommend plasma catecholamines when urinary collections are not diagnostic. Work up multiple endocrine adenomatosis, type II. Used also in diagnosis of disorders related to the nervous system and in assessment of resuscitation.

CPT Codes

82384

* The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding
is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.

Reference Range

Norepinephrine, plasma:

• 0-1 year: 0-659 pg/mL

• 1-18 years: 0-611 pg/mL

• 18 years and older: 0-874 pg/mL

Epinephrine, plasma:

• 0-1 year: 0-34 pg/mL

• 1-18 years: 0-80 pg/mL

• 18 years and older: 0-62 pg/mL

Dopamine, plasma:

• 0-1 year: 0-42 pg/mL

• 1-18 years: 0-32 pg/mL

• 18 years and older: 0-48 pg/mL