Metanephrine, Plasma; Normetanephrine, Plasma
Normetanephrine (NM) and metanephrine (MN) are the extraneuronal catechol-o-methyl transferase (COMT) metabolites of the catecholamines norepinephrine and
epinephrine, respectively. Measure of plasma metanephrines is more sensitive (but may be less specific) than measurement of catecholamines for the detection of pheochromocytoma. Proper interpretation of results requires awareness of recent medication/drug history (e.g., antihypertensive agents, alcohol, cocaine) and other preanalytical factors (e.g., stress, severe congestive heart failure, myocardial infarction) that influence release of catecholamines and metanephrines.
Overnight fasting is preferred. Patient should avoid alcohol, coffee, tea, tobacco and strenuous exercise before collection.
* This volume does not allow for repeat testing
Pre-Chill tube before collection
Tube should be kept on wet ice from removal of refrigerater, after collection, until centrifuged
Centrifuge (preferably at 4 degrees C) and separate plasma within 2 hours of collection
Preferred
Metanephrines, LC/MS/MS: < or = 57 pg/mL
Normetanephrines, LC/MS/MS: < or = 148 pg/mL
Total Metanephrines, LC/MS/MS: < or = 205 pg/mL
Detection limit for MN, NM: 25 pg/mL
Detection limit for Total: 50 pg/mL
Normetanephrine (NM) and metanephrine (MN) are the extraneuronal catechol-o-methyl transferase (COMT) metabolites of the catecholamines norepinephrine and
epinephrine, respectively. Measure of plasma metanephrines is more sensitive (but may be less specific) than measurement of catecholamines for the detection of pheochromocytoma. Proper interpretation of results requires awareness of recent medication/drug history (e.g., antihypertensive agents, alcohol, cocaine) and other preanalytical factors (e.g., stress, severe congestive heart failure, myocardial infarction) that influence release of catecholamines and metanephrines.
5 to 8 days
00913835
83835