|See Also||Lab Tests|
Levels of catecholamines along with VMA (Vanillymandelic acid) are primarily measured to diagnose hypertension secondary to pheochromocytoma. It can also be used to detect the presence of neuroblastomas and other rare adrenal tumors.
- A pheochromocytoma refers to a tumor of the chromaffin cells within the adrenal medulla that secretes abnormally high levels of the catecholamines epinephrine and norepinephrine.
- These hormones can produce peripheral arterial vasoconstriction, thereby causing episodic or persistent hypertension.
- A urine test is preferred to a blood test as catecholamine secretion from a tumor may be episodic and could be missed at any time during the day.
- The best time to perform testing is when symptoms (hypertension) of the potential adrenal tumor are significant and catecholamine production is greatest.
- No fasting required.
- Factors which can cause increased levels
- Drugs: alcohol (ethyl), aminophyll, caffeine, chloral hydrate, clonidine (prolonged therapy), contrast media (containing iodine), disulfiram, epinephrine, erythromycin, insulin, methenamine, methyldopa, nicotinic acid (large doses), nitroglycerin, quinidine, riboflavin, and tetracyclin.
- Factors which can cause decreased levels
- Drugs: guanethidine, reserpine, and salicylates
High levels indicate:
- Severe stress
- Strenuous exercise
- Acute anxiety
Low levels indicate:
- None noted
- Pheochromocytoma suppression and provocative tests
- Pagana Kathleen D, Pagana Timothy J (2006) Mosby's Manual of Diagnostic and Laboratory Tests, Mosby.