Laboratory Test Guide

Metanephrines, Fractionated, Free, Plasma

General Information

Lab Name

Metanephrines, Plasma

Lab Code

PLMET

Epic Name

Metanephrines, Plasma

Description

The most sensitive test to rule-out pheochromocytoma is plasma free metanephrines (PLMET). See also Metanephrines, Fractionated, Urine (RUFMET). For a recent review of the biochemical diagnosis of pheochromocytoma, see Pacak K et al. Nature Clin Pract Endocrinol Metab 2007; 3:92-102.PMID: 17237836

The concentration of metanephrine and normetanephine is determined by solid phase extraction followed by liquid chromatography-tandem mass spectrometry. The reportable range is 0.2 to 80.0 nmol/L for metaneprhine and normetaneprhine, respectively, with imprecision between 3.3 and 8.2 %CV.

Synonyms

Fractionated Metanephrines-Plasma, Free Metanephrines-Plasma, MEN, MEN IIA, MEN IIB, Multiple Endocrine Neoplasia, Neuroendocrine, NMN (Normetanephrines)-plasma, paraganglioma, Phaeochromocytoma, Pheochromocytoma, Soft-PMET

Components

Code	Name
MN	Metanephrine
NMN	Normetanephrine
PLMETM	Metanephrines Method, Plasma

Interpretation

Method

Serum solid phase extraction. Isotope dilution liquid chromatography mass spectrometry

Reference Range

See individual components

Ordering & Collection

Specimen Type

Plasma

Collection

3 mL blood in a LAVENDER TOP (EDTA) tube

Quantity

requested: 1.5 mL EDTA plasma
minimum: 0.5 mL EDTA plasma

Processing

Centrifuge & remove plasma - Freeze in plastic aliquot tube at -20˚C.

Performance

LIS Dept Code

Chemistry, University (CHU)

Performing Location(s)

UW-MT	Chemistry, General 206-520-4600 Clinical Lab, Room NW220, University of Washington Medical Center, 1959 NE Pacific street, Seattle, WA 98195