Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (793 page)

   With procainamide, separate cells from plasma as soon as possible to prevent loss of drug during storage.

   Hemolyzed samples are unacceptable.

CATECHOLAMINES, SERUM

   Definition

   The catecholamines (epinephrine, norepinephrine, and dopamine) are found in the adrenal medulla, neurons, and brain. All three catecholamines are derived from tyrosine and are important neurotransmitters in the CNS and also play a crucial role in the autonomic regulation of many homeostatic functions. Other names: adrenaline, catecholamine fractionation, unconjugated dopamine, epinephrine, noradrenaline, and norepinephrine.

   
Normal range:
see Table 16.16.

TABLE 16–16. Normal Range for Catecholamines

   Use

   Diagnosis of pheochromocytoma and paraganglioma, as an auxiliary test to fractionated plasma and urine metanephrine measurements.

   Diagnosis and follow-up of patients with neuroblastoma and related tumors, as an auxiliary test to urine VMA and homovanillic acid (HVA) measurements.

   Evaluation of patients with autonomic dysfunction/failure or autonomic neuropathy.

   Interpretation

Increased In (Epinephrine)

   Anger, exercise, fear, burns

   Ganglioblastoma and ganglioneuroma