
Comparison of IL‐6 measurement methods with a special emphasis on COVID‐19 patients according to equipment and sample type
Author(s) -
Choi Yu Jeong,
Roh Juhye,
Kim Sinyoung,
Lee KyungA,
Park Younhee
Publication year - 2022
Publication title -
journal of clinical laboratory analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.536
H-Index - 50
eISSN - 1098-2825
pISSN - 0887-8013
DOI - 10.1002/jcla.24182
Subject(s) - medicine , covid-19 , immunoassay , reproducibility , confidence interval , gastroenterology , immunology , chromatography , disease , chemistry , antibody , infectious disease (medical specialty)
Background Interleukin‐6 (IL‐6) is a multifunctional cytokine associated with various diseases, including coronavirus disease (COVID‐19). Although IL‐6 levels can be assessed using serum samples, use of the AFIAS (Boditech Med Inc.) automated immunoassay analyzer enables quick and simple measurement of IL‐6 levels in both serum and whole blood specimens. This study aimed to assess the correlation between IL‐6 measurements obtained from the AFIAS IL‐6 assay and Elecsys IL‐6 assay (Roche Diagnostics). Additionally, utilization of the AFIAS IL‐6 assay was evaluated. Methods The IL‐6 levels from 113 serum samples quantified using two assay systems were evaluated for their degree of correlation. Meanwhile, the linearity, analytical sensitivity, and precision/reproducibility of the AFIAS IL‐6 assay were also assessed. Results Quantification of IL‐6 with the AFIAS IL‐6 and Elecsys IL‐6 assays showed excellent agreement (kappa 0.802) and were found to be correlated (y = −0.2781 + 1.068x; 95% confidence interval: 1.007–1.124). AFIAS IL‐6 showed good analytical performances. IL‐6 levels were significantly higher in deceased patients compared to those with non‐complicated disease and those who were intubated ( p = 0.002 and p < 0.0001, respectively). Finally, IL‐6 levels more accurately predicted poor prognosis in patients, than did C‐reactive protein (area under the curve, 0.716 vs. 0.634). Conclusion The overall analytical performance of the AFIAS assay was comparable to that of the Elecsys IL‐6 assay. In light of the ongoing COVID‐19 pandemic, the AFIAS may be an attractive tool for measuring IL‐6 levels.