Evaluation of 25 OH Vitamin D in chronic renal failure and end stage renal disease subjects

Abstract

Analysis of laboratory samples from chronic renal failure (CRF) and end stage renal disease (ESRD) patients can be problematic. Current HPLC and RIA methods for the determination of 25 OH Vitamin D involve sample extraction. However, the differences between a normal and CRF or ESRD matrix can lead to interference or inaccuracy in non-extracted, automated methods now available. The objective of this study was to assess the accuracy of the non-extracted LIAISON ® 25 OH Vitamin D assay in the analysis of CRF and ESRD samples as compared against RIA as reference. Samples were collected from regional reference laboratories and analyzed in both the LIAISON ® 25 OH Vitamin D assay and the DiaSorin 25 OH Vitamin D RIA. By Student’s t test, no significant difference was observed between the RIA values and the LIAISON ® values ( P=0.07 CRF; P=0.28 ESRD). The linear regression analysis resulted in the equations: CRF: LIAISON=0.91(RIA)+0.6; r=0.82 and ESRD: LIAISON=0.93(RIA)−0.6; r=0.78. From these data we conclude that the LIAISON ® 25 OH Vitamin D assay correctly assesses the 25 OH Vitamin D status of CRF and ESRD patients.