Head-to-head comparison of two rapid high-throughput automated electrochemiluminescence immunoassays targeting total antibodies to the SARS-CoV-2 nucleoprotein and spike protein receptor binding domain

Poljak, Mario (author), Oštrbenk Valenčak, Anja (author), Štamol, Tina (author), Seme, Katja (author)

Background: Accurate anti-SARS-CoV-2 assays are needed to inform diagnostic, therapeutic, and public health decisions. The first manufacturer-independent head-to-head comparison of two rapid high-throughput automated electrochemiluminescence double-antigen sandwich immunoassays targeting total anti-SARS-CoV-2 antibodies against two different viral proteins, Elecsys Anti-SARS-CoV-2 (Elecsys-N) and Elecsys Anti-SARS-CoV-2 S (Elecsys-S) (Roche Diagnostics), was performed in a routine setting during the exponential growth phase of the epidemic’s second wave. Methods: The diagnostic specificity of Elecsys-N and Elecsys-S was initially evaluated on a panel of 572 pre−COVID-19 samples, showing 100 % specificity of both assays. Elecsys-N/Elecsys-S head-to-head comparison used 3,416 consecutive blood samples from individuals that were tested for the presence of anti-SARS-CoV-2 within commercial out-of-pocket serologic testing. Results: Elecsys-N/Elecsys-S head-to-head comparison showed overall agreement of 98.68 % (3,371/3,416; 95 % CI, 98.23–99.03 %), positive agreement of 95.16 % (884/929; 95 % CI, 93.52–96.41 %), and a high kappa value of 0.996 (95 % CI, 0.956–0.976). Previous SARS-CoV-2 PCR positivity was identified in 14/24 (58.3 %) Elecsys-N negative/Elecsys-S positive individuals and in 4/21 (19.0 %) Elecsys-N positive/Elecsys-S negative individuals. Conclusion: The first Elecsys-N/Elecsys-S head-to-head comparison showed excellent agreement of two highly specific and rapid high-throughput automated anti-SARS-CoV-2 assays. An important question is whether laboratories offering two different antibody assays could benefit from combining the assays; if so, should use be concomitant or sequential—and, in the latter case, in which order? Based on our results, we favor concomitant over sequential Elecsys-N/Elecsys-S use when testing individuals for anti-SARS-CoV-2 antibodies in high-incidence settings; for example, during the exponential or stationary growth phase of the COVID-19 epidemic.

• Language: English
• Keywords: SARS-CoV-2, immunoassay, antibody, COVID-19, electrochemiluminescence
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: MF - Faculty of Medicine
• Publication status: Published
• Publication version: Version of Record
• Year: 2021
• Number of pages: 5 str.
• Numbering: Vol. 137, art. 104784
• PID: 20.500.12556/RUL-138695
• UDC: 616.9
• ISSN on article: 1873-5967
• DOI: 10.1016/j.jcv.2021.104784
• COBISS.SI-ID: 61796611
• Publication date in RUL: 09.08.2022

Record is a part of a journal

• Title: Journal of clinical virology
• Publisher: Elsevier
• ISSN: 1873-5967
• COBISS.SI-ID: 23214341

Licences

• License: CC BY-NC-ND 4.0, Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
• Link: http://creativecommons.org/licenses/by-nc-nd/4.0/
• Description: The most restrictive Creative Commons license. This only allows people to download and share the work for no commercial gain and for no other purposes.

Secondary language

• Language: Slovenian
• Keywords: SARS-CoV-2, imunski test, protitelesa