Catecholamines, Blood and Urine


Epinephrine, norepinephrine, dopamine.

To assist in diagnosing catecholamine-secreting tumors, such as those found in the adrenal medulla, and in the investigation of hypertension. The test is used to assist in diagnosing pheochromocytoma (a benign tumor of the adrenal gland) and paraganglioma; also as a work-up of neuroblastoma (a rare tumor that most often originates in the nervous tissue of the adrenal medulla).

Patient Preparation
Instruct the patient to follow a normal-sodium diet for 3 days before testing, to avoid consumption of foods high in amines for 48 hr before testing, and to withhold food and fluids for 10 to 12 hr before the test. Instruct the patient to avoid self-prescribed medications for 2 wk before testing (especially appetite suppressants and cold and allergy medications, such as nose drops, cough suppressants, and bronchodilators). Instruct the patient to withhold prescribed medication (especially methyldopa, epinephrine, levodopa, and methenamine mandelate) by medical direction. Protocols may vary among facilities. The patient should also abstain from smoking tobacco for 24 hr before testing. Usually, a 24-hr urine collection is ordered. Instruct the patient to avoid excessive exercise and stress during the 24-hr collection of urine. As appropriate, provide the required urine collection container and specimen collection instructions.

Normal Findings
Method: High-performance liquid chromatography.

BloodConventional UnitsSI Units
Epinephrine (supine)(Conventional Units × 5.46)
  ChildLess than 450 pg/mLLess than 2,457 pmol/L
  AdultLess than 200 pg/mLLess than 1,092 pmol/L
Norepinephrine (supine)(Conventional Units × 5.91)
  ChildLess than 1,200 pg/mLLess than 7,100 pmol/L
  AdultLess than 410 pg/mLLess than 2,420 pmol/L
Dopamine (supine or upright)(Conventional Units × 6.53)
  Child–adultLess than 20 pg/mLLess than 130 pmol/L
Generally, higher values are expected in specimens collected when the patient has been standing; dopamine values are unaffected by position.
UrineConventional UnitsSI Units
Epinephrine(Conventional Units × 5.46)
  ChildLess than 11 mcg/24 hrLess than 60 nmol/24 hr
  AdultLess than 20 mcg/24 hrLess than 100 nmol/24 hr
Norepinephrine(Conventional Units × 5.91)
  ChildLess than 50 mcg/24 hrLess than 300 nmol/24 hr
  AdultLess than 120 mcg/24 hrLess than 709 nmol/24 hr
Dopamine(Conventional Units × 6.53)
  ChildLess than 414 mcg/24 hrLess than 2,703 nmol/24 hr
  AdultLess than 485 mcg/24 hrLess than 3,167 nmol/24 hr
Due to the numerous factors that can elevate catecholamines, urine specimens are thought to provide more reliable results in the pediatric population.

Critical Findings and Potential Interventions

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