A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # |
Metanephrines, Fractionated, Free, LC/MS/MS, Plasma
MessageOvernight fasting is required.
Patient should be relaxed in either a supine or upright position before blood draw.
*Specimen is collected in a prechilled tube and transported to processing on ice.
FREEZE EDTA PLASMA
Patient should be relaxed in either a supine or upright position before blood draw.
*Specimen is collected in a prechilled tube and transported to processing on ice.
FREEZE EDTA PLASMA
Test Code
19548
Alias/See Also
LAB10008
CPT Codes
83835
Includes
Metanephrine, Free
Normetanephrine, Free
Total, Free (MN + NMN)
Normetanephrine, Free
Total, Free (MN + NMN)
Preferred Specimen
2.5 mL plasma collected in an EDTA (lavender-top) tube
Patient Preparation
Patients should be relaxed in either a supine or upright position before blood is drawn.
Patient should avoid alcohol, coffee, tea, tobacco and strenuous exercise prior to collection. Overnight fasting is preferred.
Minimum Volume
1.5 mL
Instructions
Draw specimen in a pre-chilled EDTA lavender-top Vacutainer™. The whole blood sample should be kept on wet ice until centrifuged (preferably at 4° C) to separate the plasma within 2 hours of venipuncture. After centrifugation, the plasma should be transferred to a transport tube and immediately refrigerated.
Transport Container
Transport tube
Transport Temperature
Refrigerated (cold packs)
Specimen Stability
Room temperature: 24 hours
Refrigerated: 14 days
Frozen: 30 days
Refrigerated: 14 days
Frozen: 30 days
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Heparinized plasma • Serum • CSF • Urine
Methodology
Chromatography/Mass Spectrometry
FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.
Setup Schedule
Mon-Sat
Report Available
5-6 days
Limitations
False-positive results have been observed in patients with either chronic kidney disease or hypertension.
Reference Range
Metanephrine, Free | ≤57 pg/mL |
Normetanephrine, Free | ≤148 pg/mL |
Total, Free (MN + NMN) | ≤205 pg/mL |
Clinical Significance
Normetanephrine (NM) and metanephrine (MN) are the extra-neuronal catechol-o-methyl transferase (COMT) metabolites of the catecholamines norepinephrine and epinephrine, respectively. Measurement of plasma metanephrines is more sensitive (but may be less specific) than measurement of catecholamines for the detection of heochromocytoma. Proper interpretation of results requires awareness of recent medication/drug history (e.g., antihypertensive agents, alcohol, cocaine) and other pre-analytical factors (e.g., stress, severe congestive heart failure, myocardial infarction) that influence release of catecholamines and metanephrines.
Performing Laboratory
Quest Diagnostics Nichols Institute-San Juan Capistrano, CA |
33608 Ortega Highway |
San Juan Capistrano, CA 92675-2042 |