Quantitation of urine normetanephrine (NMN) and metanephrine (MN), collectively referred to as “metanephrines,” together with plasma metanephirne levels is useful as the initial screen to aid in the diagnosis and follow-up of catecholamine-producing tumors, pheochromocytoma and paraganglioma. 24-hr urine is highly recommended.
Biochemical Evaluation and Diagnosis of Catecholamine-producing Tumors
Patients should be off Buspirone (“Buspar") for 72 hours before collection as the drug may cause false elevations of metanephrine.
Patients should be off of Sinemet (Levodopa or Carbidopa), L-Dopa, Aldomet (Methyldopa) and methanamine mandelate (Hiprex, Mandelamine, Urex) for 1 week (minimum of 48 hours) prior to collection.
Monday, Wednesday, Friday
Samples must be in the performing department by 8am on the day of testing for results the same day
Waters Acquity UPLX XEVO TQ-S Tandem Mass Spectrometry System
Normetanephrine: 50-840 ug/24 hr
Metanephrine: 0-370 ug/24 hr
Reference ranges are based on hypertensive population results