English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Summary 				 Determination of 25-hydroxyvitamin D [25(OH)D] represents a unique challenge, considering its lipophilic na - ture. Considering the widespread prevalence of vitamin D deficiency, which leads to increasing number of requests for 25(OH)D determination, immunoassay measurements adjusted to automated analyzers are being developed. Because of the variability among assays, it is often difficult to monitor vitamin D status and supplementation. The aim of this study was to compare the results of two immunoassays with high performance liquid chromatography with ultraviolet detection (HPLC-UV). Also, the aim was to estimate vitamin D status, since up to date the prevalence of vitamin D deficiency in Serbia was not examined. We have evaluated analytical characteristics of two automated immunoassays for 25(OH)D determination, from Roche (CobasR e601) and Abbott (Architect). For comparison studies we used HPLC analysis of 25-(OH)-Vitamin D3/D2 from Chromsystems (Waters isocratic system). In order to estimate vitamin D status in general population, we have searched the database of the laboratory information system and analyzed the data from 533 patients whose 25(OH)D was determined together with intact parathyroid hormone (iPTH). For imprecision assessment, four serum pools were prepared with following 25(OH)D concentrations: 35 nmol/L, ∼50 nmol/L, ∼75 nmol/L and ∼125 nmol/L. Obtai ned CVs for Roche method were 1.5-2.8% for within-run and 4.0-6.7% for between-run imprecision. For Abbott method, CVs were 0.7-4.4% for within- run and 3.8-7.2% for between-run imprecision. Inaccuracy was analyzed with commercial control sera. Obtained deviations from target value were 2.1% for Roche assay and 1.3-1.5% for Abbott method, and were not statistically significant (P&gt;0.05). Comparison of Roche and HPLC-UV methods using Passing-Bablok regression analysis gave the following equation for the regression line y=0.937x+9.518 (r=0.739; n=97) and the regression line equation from the comparison of Abbott and HPLC-UV methods was y=0.745x+10.343 (r=0.793; n=97). Mean difference and SD for Bland-Altman plot were -4.5 nmol/L and 21.75 nmo/L, respectively for Roche method and 6.4 nmol/L and 18.8 nmol/L, respectively for Abbott. Statistical analysis (Chi-square test) of frequency distribution among different vitamin D status categories ( 75 nmol/L sufficiency) showed that the frequency distribution obtained with Abbott method was significantly different from the distribution of the HPLC results, in contrast to Roche results frequency distribution which did not differ significantly. Also, statistical analysis of the agreement between the three methods for each vitamin D status category showed that results of both Roche and Abbott methods were significantly higher than HPLC in the two deficiency categories (P=0.005 for Roche, P=0.0407 for Abbott), and in the sufficiency category Abbott method significantly underestimated concentration of 25(OH)D compared to HPLC results (P 75 nmol/L).

journal of medical biochemistry

Comparison of three different methods for 25(oh)-vitamin d determination and vitamin d status in general population – Serbian experience / Poređenje tri različite metode za određivanje 25(oh)-vitamina D i statusa vitamina D u opštoj populaciji – srpsko iskustvo