Biomaterial Database

Harmonization of LC-MS/MS Measurements of Plasma Free Normetanephrine, Metanephrine, and 3-Methoxytyramine. 2021

Mirko Peitzsch, and Talia Novos, and Denise Kaden, and Max Kurlbaum, and Antonius E van Herwaarden, and Daniel Müller, and Jo Adaway, and Eric Grouzmann, and Brett McWhinney, and Kirsten Hoad, and Gerald Woollard, and Ido Kema, and Christopher Boot, and Martin Fassnacht, and Fred Sweep, and Tze P Loh, and Andrea R Horvath, and Graeme Eisenhofer

Institute of Clinical Chemistry and Laboratory Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.

Plasma-free normetanephrine and metanephrine (metanephrines) are the recommended biomarkers for testing of pheochromocytoma and paraganglioma (PPGL). This study evaluated the status of harmonization of liquid chromatography-tandem mass spectrometry-based measurements of plasma metanephrines and methoxytyramine and clinical interpretation of test results. 125 plasma samples from patients tested for PPGLs were analyzed in 12 laboratories. Analytical performance was also assessed from results of a proficiency-testing program. Agreement of test results from different laboratories was assessed by Passing-Bablok regression and Bland-Altman analysis. Agreement in clinical test interpretation based on laboratory specific reference intervals was also examined. Comparisons of analytical test results by regression analysis revealed strong correlations for normetanephrine and metanephrine (R ≥ 0.95) with mean slopes of 1.013 (range 0.975-1.078), and 1.019 (range 0.963-1.081), and intercepts of -0.584 (-53.736 to 54.790) and -3.194 (-17.152 to 5.933), respectively. The mean bias between methods was 1.2% (-11.6% to 16.0%) for metanephrine and 0.1% (-18.0% to 9.5%) for normetanephrine. Measurements of 3-methoxytyramine revealed suboptimal agreement between laboratories with biases ranging from -32.2% to 64.0%. Interrater agreement in test interpretation was >94% for metanephrine and >84% for normetanephrine; improvements in interrater agreement were observed with use of harmonized reference intervals, including age-specific cut-offs for normetanephrine. Analytical methods for metanephrines are well harmonized between laboratories. However, the 16% disagreement in test interpretation for normetanephrine suggests use of suboptimal method-dependent reference intervals for clinical decision-making for this metabolite. Improved analytical methods and reference interval harmonization are particularly required for 3-methoxytyramine.

UI	MeSH Term	Description	Entries
D008676	Metanephrine	Product of epinephrine O-methylation. It is a commonly occurring, pharmacologically and physiologically inactive metabolite of epinephrine.	Metadrenaline
D009647	Normetanephrine	A methylated metabolite of norepinephrine that is excreted in the urine and found in certain tissues. It is a marker for tumors.	3-Methoxynoradrenaline,Normetadrenaline,3 Methoxynoradrenaline
D002853	Chromatography, Liquid	Chromatographic techniques in which the mobile phase is a liquid.	Liquid Chromatography
D004298	Dopamine	One of the catecholamine NEUROTRANSMITTERS in the brain. It is derived from TYROSINE and is the precursor to NOREPINEPHRINE and EPINEPHRINE. Dopamine is a major transmitter in the extrapyramidal system of the brain, and important in regulating movement. A family of receptors (RECEPTORS, DOPAMINE) mediate its action.	Hydroxytyramine,3,4-Dihydroxyphenethylamine,4-(2-Aminoethyl)-1,2-benzenediol,Dopamine Hydrochloride,Intropin,3,4 Dihydroxyphenethylamine,Hydrochloride, Dopamine
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000310	Adrenal Gland Neoplasms	Tumors or cancer of the ADRENAL GLANDS.	Adrenal Cancer,Adrenal Gland Cancer,Adrenal Neoplasm,Cancer of the Adrenal Gland,Neoplasms, Adrenal Gland,Adrenal Cancers,Adrenal Gland Cancers,Adrenal Gland Neoplasm,Adrenal Neoplasms,Cancer, Adrenal,Cancer, Adrenal Gland,Cancers, Adrenal,Cancers, Adrenal Gland,Neoplasm, Adrenal,Neoplasm, Adrenal Gland,Neoplasms, Adrenal
D053719	Tandem Mass Spectrometry	A mass spectrometry technique using two (MS/MS) or more mass analyzers. With two in tandem, the precursor ions are mass-selected by a first mass analyzer, and focused into a collision region where they are then fragmented into product ions which are then characterized by a second mass analyzer. A variety of techniques are used to separate the compounds, ionize them, and introduce them to the first mass analyzer. For example, for in GC-MS/MS, GAS CHROMATOGRAPHY-MASS SPECTROMETRY is involved in separating relatively small compounds by GAS CHROMATOGRAPHY prior to injecting them into an ionization chamber for the mass selection.	Mass Spectrometry-Mass Spectrometry,Mass Spectrometry Mass Spectrometry,Mass Spectrometry, Tandem