Please use this identifier to cite or link to this item: https://dora.health.qld.gov.au/qldresearchjspui/handle/1/6634
Title: Harmonization of LC-MS/MS Measurements of Plasma Free Normetanephrine, Metanephrine, and 3-Methoxytyramine.
Authors: Mirko Peitzsch
Novos T
Kaden D
Kurlbaum M
Antonius Eduard van Herwaarden
Müller D
Adaway J
Grouzmann E
McWhinney B 
Hoad K
Gerald Woollard
Kema I
Boot C
Fassnacht M
Sweep F
Tze Ping Loh
Horvath AR
Eisenhofer G
Issue Date: 2021
Journal: Clinical chemistry
Abstract: 

Background

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.

Methods

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.

Results

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.

Conclusions

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.
Type: Journal Article
Appears in Sites:Queensland Health Publications

Show full item record

Page view(s)

58
checked on Apr 24, 2025

Google ScholarTM

Check


Items in DORA are protected by copyright, with all rights reserved, unless otherwise indicated.