Home
HelpTest Code MF24U Metanephrines, Fractionated, 24 Hour, Urine
Reporting Name
Metanephrines, Fractionated, 24h, UUseful For
A first- and second-order screening test for the presumptive diagnosis of catecholamine-secreting pheochromocytomas and paragangliomas
Confirming positive plasma metanephrine results
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Specimen Type
UrineAdvisory Information
Necessary Information
24-Hour volume is required.
Specimen Required
Patient Preparation: Tricyclic antidepressants, labetalol, and sotalol medications may elevate levels of metanephrines producing results that cannot be interpreted. If clinically feasible, it is optimal to discontinue these medications at least 1 week before collection. For advice on assessing the risk of removing patients from these medications and alternatives, consider consultation with a specialist in endocrinology or hypertension.
Supplies: Urine Tubes, 10 mL (T068)
Container/Tube: Plastic urine tube
Specimen Volume: 10 mL
Collection Instructions:
1. Collect urine for 24 hours.
2. Add 10 g (pediatric: 3 g) of boric acid or 25 mL (pediatric: 15 mL) of 50% acetic acid as preservative at start of collection.
Additional Information: See Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens in Special Instructions for multiple collections.
Specimen Minimum Volume
2 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Urine | Refrigerated (preferred) | 28 days | |
| Ambient | 28 days | ||
| Frozen | 28 days |
Special Instructions
Reference Values
METANEPHRINE
Males
Normotensives
3-8 years: 29-92 mcg/24 hours
9-12 years: 59-188 mcg/24 hours
13-17 years: 69-221 mcg/24 hours
≥18 years: 44-261 mcg/24 hours
Reference values have not been established for patients that are <36 months of age.
Hypertensives: <400 mcg/24 hours
Females
Normotensives
3-8 years: 18-144 mcg/24 hours
9-12 years: 43-122 mcg/24 hours
13-17 years: 33-185 mcg/24 hours
≥18 years: 30-180 mcg/24 hours
Reference values have not been established for patients that are <36 months of age.
Hypertensives: <400 mcg/24 hours
NORMETANEPHRINE
Males
Normotensives
3-8 years: 34-169 mcg/24 hours
9-12 years: 84-422 mcg/24 hours
13-17 years: 91-456 mcg/24 hours
18-29 years: 103-390 mcg/24 hours
30-39 years: 111-419 mcg/24 hours
40-49 years: 119-451 mcg/24 hours
50-59 years: 128-484 mcg/24 hours
60-69 years: 138-521 mcg/24 hours
≥70 years: 148-560 mcg/24 hours
Reference values have not been established for patients that are <36 months of age.
Hypertensives: <900 mcg/24 hours
Females
Normotensives
3-8 years: 29-145 mcg/24 hours
9-12 years: 55-277 mcg/24 hours
13-17 years: 57-286 mcg/24 hours
18-29 years: 103-390 mcg/24 hours
30-39 years: 111-419 mcg/24 hours
40-49 years: 119-451 mcg/24 hours
50-59 years: 128-484 mcg/24 hours
60-69 years: 138-521 mcg/24 hours
≥70 years: 148-560 mcg/24 hours
Reference values have not been established for patients that are <36 months of age.
Hypertensives: <900 mcg/24 hours
TOTAL METANEPHRINE
Males
Normotensives
3-8 years: 47-223 mcg/24 hours
9-12 years: 201-528 mcg/24 hours
13-17 years: 120-603 mcg/24 hours
18-29 years: 190-583 mcg/24 hours
30-39 years: 200-614 mcg/24 hours
40-49 years: 211-646 mcg/24 hours
50-59 years: 222-680 mcg/24 hours
60-69 years: 233-716 mcg/24 hours
≥70 years: 246-753 mcg/24 hours
Reference values have not been established for patients that are <36 months of age.
Hypertensives: <1,300 mcg/24 hours
Females
Normotensives
3-8 years: 57-210 mcg/24 hours
9-12 years: 107-394 mcg/24 hours
13-17 years: 113-414 mcg/24 hours
18-29 years: 142-510 mcg/24 hours
30-39 years: 149-535 mcg/24 hours
40-49 years: 156-561 mcg/24 hours
50-59 years: 164-588 mcg/24 hours
60-69 years: 171-616 mcg/24 hours
≥70 years: 180-646 mcg/24 hours
Reference values have not been established for patients that are <36 months of age.
Hypertensives: <1,300 mcg/24 hours
For SI unit Reference Values, see https://www.mayocliniclabs.com/order-tests/si-unit-conversion.html
Day(s) and Time(s) Performed
Monday through Friday; 4 p.m.
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.CPT Code Information
83835
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| METAF | Metanephrines, Fractionated, 24h, U | In Process |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 8552 | Metanephrine, U | 19049-6 |
| 21545 | Normetanephrine, U | 2671-6 |
| 83006 | Total Metanephrines, U | 2609-6 |
| TM50 | Collection Duration | 13362-9 |
| VL48 | Urine Volume | 3167-4 |
| 2434 | Comment | 48767-8 |
Clinical Reference
1. van Duinen N, Corssmit EPM, de Jong WHA, et al: Plasma levels of free metanephrines and 3-methoxytyramine indicate a higher number of biochemically active HNPGL than 24-h urinary excretion rates of catecholamines and metabolites European J Endocrinol 2013;169:377-382 doi: 10.1530/EJE-13-0529
2. Pacak K, Linehan WM, Eisenhofer G, et al: Recent advances in genetics, diagnosis, localization, and treatment of pheochromocytoma. Ann Intern Med 2001;134:315-329
3. Sawka AM, Singh RJ, Young WF Jr: False positive biochemical testing for pheochromocytoma caused by surreptitious catecholamine addition to urine. Endocrinologist 2001;11:421-423
4. Eisenhofer G, Grebe S, Cheung NKV: Chapter 63: Monoamine-Producing Tumors. In Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. Sixth edition. Edited by N Rafai, AR Horvath, CT Wittwer. Elsevier, 2018. pp 1421
5. Shen Y, Cheng L: Chapter 2: Biochemical Diagnosis of Pheochromocytoma and Paraganglioma. In Paraganglioma: A Multidisciplinary Approach. Edited by R. Mariani-Costantini. Codon Publications; 2019. doi:10.15586/paraganglioma.2019.ch2. Accessed: April 2020. Available at: www.ncbi.nlm.nih.gov/books/NBK543224/
Method Description
Urinary metanephrines are determined by reverse phase liquid chromatography-tandem mass spectrometry (LC-MS/MS) stable isotope dilution analysis. Urinary metanephrines occur largely in conjugated form. After urine specimens are acidified and hydrolyzed for 20 minutes in a boiling water bath, metanephrine and normetanephrine are extracted from the specimens utilizing extraction cartridges. The metanephrine and normetanephrine are eluted from the cartridge using 20% methanol (MeOH) and analyzed by LC-MS/MS using multiple reaction monitoring in positive mode. Deuterated metanephrine (d3-metanephrine, 200 ng) and deuterated normetanephrine (d3-normetanephrine, 500 ng) are added prior to the hydrolysis as an internal standard. The following ion pairs are used for analysis: metanephrine, (180/148); normetanephrine, (166/134); d3-metanephrine, (183/151); d3-normetanephrine, (169/137). The metanephrine and normetanephrine concentrations are quantified using ratios of the peak areas to deuterium-labeled internal standards by LC-MS/MS. A calibration curve, generated from 20% MeOH spiked standards, is included with each batch of patient specimens.(Taylor RL, Singh RJ: Validation of liquid chromatography-tandem mass spectometry method for analysis of urinary conjugated metanephrine and normetanephrine for screening of pheochromocytoma. Clin Chem 2002;48:533-539; Roden M, Raffesberg W, Raber W, et al: Quantification of unconjugated metanephrine in human plasma without interference by acetaminophen. Clin Chem 2001;47:1061-1067)
Analytic Time
3 days (not reported on Sundays)Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Method Name
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) Stable Isotope Dilution Analysis
Forms
If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen.