Evaluation of a New Generation Automated Assay for 25-Hydroxy Vitamin D Based on Competitive Protein Binding

Abstract

Background The interest for vitamin D has exponentially increased testing demand for 25-hydroxy vitamin D [25(OH)D]. Consequently, many laboratories are switching from LC-MS/MS methods to automated, high-throughput immunoassays. One of the major potential issues with these assays has been the lack of cross-reactivity with 25(OH)D2. Methods We have evaluated the Roche Elecsys vitamin D total II assay for accuracy by comparing 79 patient samples with LC-MS/MS. The cross-reactivity for 25(OH)D2 was evaluated by analyzing samples with high 25(OH)D2 separately and estimating 25(OH)D2 recovery, as well as by spiking of 25(OH)D2. The assay was further evaluated for precision, linearity, sample type, and common interferences. Results There was mostly good agreement between the Elecsys and LC-MS/MS assays (Deming regression: y = 0.95x + 0.70), with an overall bias of 2.3% (−0.84 ng/mL). However, there were 6 out of 79 (7.6%) discordant samples. The Deming regression for samples with high 25(OH)D2 compared to LC-MS/MS showed similar slope and intercept (y = 0.97x − 1.1). The average recovery of 25(OH)D2 for these samples was 90%. The initial precision studies were in general agreement with the package insert, but long-term clinical use showed higher-than-claimed imprecision (11.7%–14.4% at 12 ng/mL and 6.9%–7.6% at 27 ng/mL; claimed: 7.2% and 5.0%, respectively). We observed 1 falsely high result in plasma, an issue previously addressed by Roche in a medical device correction. Conclusions The analytical performance of the Roche Vitamin D assay was acceptable, and the assay had a good cross-reactivity for 25(OH)D2.

Persistence of Anti-SARS-CoV-2 Antibodies Six Months after Infection in an Outbreak with Five Hundred COVID-19 Cases in Borriana (Spain): A Prospective Cohort Study

“…The first blood samples were not available for a simultaneous analysis with the second samples. We also explored the potential associations [9][10][11][12] with COVID-19 of ABO blood groups, ascertained by the gel test (ID-Card ABO/RhD, DiaMed GmbH, Bio-Rad Laboratories Switzerland) [13] and 25-hydroxy vitamin D [25(OH)D] levels, determined by electrochemiluminisence-based assay (Elecsys vitamin D total II Roche Diagnostic, Germany) [14].…”

“…1 CI = Confidence interval;2 Adjusted for age sex ABO, occupation current smoker physical exercise alcohol consumption; 3 Adjusted for sex ABO;4 Adjusted for ABO age;5 Adjusted for sex age 6. Adjusted for age ABO sex;7 Adjusted for age sex ABO occupation;8 Adjusted for age sex ABO current smoker physical exercise alcohol beverage; 9 NC = No computable;10 Adjusted for age sex ABO chronic illness current smoker physical exercise alcohol consumption assistance mass gathering events ≥ 2 and over;11 Adjusted for age, sex ABO occupation current smoker physical exercise alcohol consumption assistance mass gathering events ≥ 2 and over;12 Excluding participants with symptoms before 6 March or after 31 March 2020;13 Adjusted for age, sex, ABO, occupation, current smoker physical exercise alcohol consumption assistance mass gathering events ≥ 2 and over;14 Adjusted for age sex, ABO, chronic illness occupation 15. Adjusted by age, sex, body mass index, ABO, chronic illness.…”

“…RR = Relative risk; 2 CI = Confidence interval;3 Missing information for 1 participant;4 Missing information for 3 participants;5 Missing information for 3 participants;6 Missing information for 16 participants;7 Missing information for 14 participants;8 Missing information for 4 participants;9 Missing information for 1 participant;10 Missing information for 7 participants;11 Excluding participants with COVID-19 symptoms before 6 March or after 31 March 2020;12 Missing information for 1 participant;13 Missing information for 1 participant;14 Missing information for 2 participants;15 Missing information for 1 participant.…”

Simultaneous determination of VD2, VD3, 25(OH) D2, and 25(OH) D3 in human plasma using electrospray LC–MS/MS as well as its application to evaluate VD plasma levels in depressive, schizophrenic patients and healthy individuals

“…Plasma 25(OH) D concentration is a key marker of a patient’s vitamin D levels, which can be determined by competitive binding assays (Musteata & Musteata, 2011), radioimmunoassay (van den Ouweland, Beijers, Demacker, & van Daal, 2010), high‐ performance liquid chromatography (HPLC), automated immunoassays (Asif, Groboske, Leung, Yeo, & van Wijk, 2019) and liquid chromatography–tandem mass spectrometry (Higashi, Shimada, & Toyo'oka, 2010; van den Ouweland et al, 2010; van den Ouweland, Vogeser, & Bacher, 2013), which has become the “gold standard” for vitamin D plasma concentration measurements in recent years (Galior, Ketha, Grebe, & Singh, 2018). The analysis of 25(OH) D is technically demanding owing to its hydrophobic nature and strong protein binding.…”

Association of vitamin D status withall‐causemortality and outcomes among Chinese individuals with diabetic foot ulcers

“…In the UK, the total annual cost of management of DFUs was estimated to exceed $1.32 billion 56 . Recently, a single‐center retrospective review in China showed that the total cost of DFUs management per patient was $6,217.80 in 2020, with an average of $3,228.20, and it has tended to increase year by year 57 . Thus, if adequate vitamin D concentrations were beneficial to the improvement of the state of wound healing, vitamin D supplementation, as a potential therapeutic for DFUs, would be a safe, economical, and widely available method to improve prognosis and reduce mortality among individuals with DFU.…”