Test Overview
Test Methodology

Liquid Chromatography - Tandem Mass Spectrometry (LC-MS/MS)

Test Usage

Screening test for presumptive diagnosis of catecholamine-secreting pheochromocytomas or paragangliomas.

Reference Range *

Metanephrine, Plasma <0.5 nmol/L
Normetanephrine, Plasma <0.9 nmol/L

Test Limitations

While most circulating metanephrines are derived directly from adrenal secretion, peripheral conversion of catecholamines makes a small contribution. Therefore, substances that increase endogenous catecholamine levels can result in borderline elevations of plasma metanephrines. These include monamine oxidase inhibitors (MOIs), catecholamine reuptake inhibitors, and some anesthetic gases, particularly halothane. Artifactually decreased plasma metanephrine levels may be observed when patients are already receiving metyrosine treatment.

Test Details
Days Set Up
Wednesday, Friday
Analytic Time

8 hours

Soft Order Code
PMETN
MiChart Code
Metanephrines, Plasma Fractions
Synonyms
  • Normetanephrines, Plasma
  • Fractionated Metanephrines, Plasma
  • PMET
  • Metanephrines, Fract., Free, P
Laboratory
Chemical Pathology
Section
Drug Analysis
Specimen Requirements
Collection

Collect specimen in a lavender top tube. Centrifuge, aliquot plasma into a plastic vial and freeze. Discontinue epinephrine and epinephrine-like drugs at least 1 week before obtaining the specimen. The patient must fast and abstain from smoking tobacco for at least 4 hours before the specimen is drawn. The patient may drink only water during the fasting period.

Special Handling

Fasting specimen.

Lavender Top Tube
Normal Volume
1 mL EDTA plasma
Minimum Volume
0.5 mL EDTA plasma
Billing
CPT Code
83835
Fee Code
KA017
LOINC
25474-8
NY State Approved
No