tetano
Editor, Senior Moderator
Clin Chem Lab Med
. 2021 Jan 14;cclm-2020-1758.
doi: 10.1515/cclm-2020-1758. Online ahead of print.
Evaluation of four commercial, fully automated SARS-CoV-2 antibody tests suggests a revision of the Siemens SARS-CoV-2 IgG assay
Christian Irsara[SUP] 1 [/SUP], Alexander E Egger[SUP] 1 [/SUP], Wolfgang Prokop[SUP] 1 [/SUP], Manfred Nairz[SUP] 2 [/SUP], Lorin Loacker[SUP] 1 [/SUP], Sabina Sahanic[SUP] 2 [/SUP], Alex Pizzini[SUP] 2 [/SUP], Thomas Sonnweber[SUP] 2 [/SUP], Wolfgang Mayer[SUP] 3 [/SUP], Harald Schennach[SUP] 3 [/SUP], Judith Loeffler-Ragg[SUP] 2 [/SUP], Rosa Bellmann-Weiler[SUP] 2 [/SUP], Ivan Tancevski[SUP] 2 [/SUP], G?nter Weiss[SUP] 2 [/SUP], Markus Anliker[SUP] 1 [/SUP], Andrea Griesmacher[SUP] 1 [/SUP], Gregor Hoermann[SUP] 1 4 [/SUP]
Affiliations
Abstract
Objectives: Serological tests detect antibodies against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in the ongoing coronavirus disease-19 (COVID-19) pandemic. Independent external clinical validation of performance characteristics is of paramount importance.
Methods: Four fully automated assays, Roche Elecsys Anti-SARS-CoV-2, Abbott SARS-CoV-2 IgG, Siemens SARS-CoV-2 total (COV2T) and SARS-CoV-2 IgG (COV2G) were evaluated using 350 pre-pandemic samples and 700 samples from 245 COVID-19 patients (158 hospitalized, 87 outpatients).
Results: All tests showed very high diagnostic specificity. Sensitivities in samples collected at least 14 days after disease onset were slightly lower than manufacturers' claims for Roche (93.0%), Abbott (90.8%), and Siemens COV2T (90.3%), and distinctly lower for Siemens COV2G (78.8%). Concordantly negative results were enriched for immunocompromised patients. ROC curve analyses suggest a lowering of the cut-off index for the Siemens COV2G assay. Finally, the combination of two anti-SARS-CoV-2 antibody assays is feasible when considering borderline reactive results.
Conclusions: Thorough on-site evaluation of commercially available serologic tests for detection of antibodies against SARS-CoV-2 remains imperative for laboratories. The potentially impaired sensitivity of the Siemens COV2G necessitates a switch to the company's newly filed SARS-CoV-2 IgG assay for follow-up studies. A combination of tests could be considered in clinical practice.
Keywords: COVID-19; SARS-CoV-2 antibody; orthogonal testing; sensitivity; serologic tests; specificity.
. 2021 Jan 14;cclm-2020-1758.
doi: 10.1515/cclm-2020-1758. Online ahead of print.
Evaluation of four commercial, fully automated SARS-CoV-2 antibody tests suggests a revision of the Siemens SARS-CoV-2 IgG assay
Christian Irsara[SUP] 1 [/SUP], Alexander E Egger[SUP] 1 [/SUP], Wolfgang Prokop[SUP] 1 [/SUP], Manfred Nairz[SUP] 2 [/SUP], Lorin Loacker[SUP] 1 [/SUP], Sabina Sahanic[SUP] 2 [/SUP], Alex Pizzini[SUP] 2 [/SUP], Thomas Sonnweber[SUP] 2 [/SUP], Wolfgang Mayer[SUP] 3 [/SUP], Harald Schennach[SUP] 3 [/SUP], Judith Loeffler-Ragg[SUP] 2 [/SUP], Rosa Bellmann-Weiler[SUP] 2 [/SUP], Ivan Tancevski[SUP] 2 [/SUP], G?nter Weiss[SUP] 2 [/SUP], Markus Anliker[SUP] 1 [/SUP], Andrea Griesmacher[SUP] 1 [/SUP], Gregor Hoermann[SUP] 1 4 [/SUP]
Affiliations
- PMID: 33554557
- DOI: 10.1515/cclm-2020-1758
Abstract
Objectives: Serological tests detect antibodies against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in the ongoing coronavirus disease-19 (COVID-19) pandemic. Independent external clinical validation of performance characteristics is of paramount importance.
Methods: Four fully automated assays, Roche Elecsys Anti-SARS-CoV-2, Abbott SARS-CoV-2 IgG, Siemens SARS-CoV-2 total (COV2T) and SARS-CoV-2 IgG (COV2G) were evaluated using 350 pre-pandemic samples and 700 samples from 245 COVID-19 patients (158 hospitalized, 87 outpatients).
Results: All tests showed very high diagnostic specificity. Sensitivities in samples collected at least 14 days after disease onset were slightly lower than manufacturers' claims for Roche (93.0%), Abbott (90.8%), and Siemens COV2T (90.3%), and distinctly lower for Siemens COV2G (78.8%). Concordantly negative results were enriched for immunocompromised patients. ROC curve analyses suggest a lowering of the cut-off index for the Siemens COV2G assay. Finally, the combination of two anti-SARS-CoV-2 antibody assays is feasible when considering borderline reactive results.
Conclusions: Thorough on-site evaluation of commercially available serologic tests for detection of antibodies against SARS-CoV-2 remains imperative for laboratories. The potentially impaired sensitivity of the Siemens COV2G necessitates a switch to the company's newly filed SARS-CoV-2 IgG assay for follow-up studies. A combination of tests could be considered in clinical practice.
Keywords: COVID-19; SARS-CoV-2 antibody; orthogonal testing; sensitivity; serologic tests; specificity.