Measurement of Circulating 1,25-Dihydroxyvitamin D: Comparison of an Automated Method with a Liquid Chromatography Tandem Mass Spectrometry Method.

ABSTRACT: Background. The clinical relevance of circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) is probably underappreciated, but variations in the measurement of this difficult analyte between different methods limit comparison of results. Methods. In 129 clinical samples, we compared a new automated assay with a commercially available liquid chromatography tandem mass spectrometry (LC-MS/MS) kit. Results. Median (interquartile range) 1,25(OH)2D concentrations with the automated assay and the LC-MS/MS method were 26.6 pg/mL (18.5-39.0 pg/mL) and 23.6 pg/mL (16.1-31.3 pg/mL), respectively (P = 0.001). Using the method-specific cut-offs for deficient 1,25(OH)2D levels (<20 pg/mL for the automated assay and <17 pg/mL for the LC-MS/MS method), the percentage of patients classified as 1,25(OH)2D defici

SUBMITTER: Zittermann A 

PROVIDER: S-EPMC4835639 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature