| Autor: |
Schaffner A; Landesspital Liechtenstein, Heiligkreuz, 9490 Vaduz, Liechtenstein., Risch L; Labormedizinisches Zentrum Dr Risch, Wuhrstrasse 14, 9490 Vaduz, Liechtenstein.; Faculty of Medical Sciences, Private Universität im Fürstentum Liechtenstein, Dorfstrasse 24, 9495 Triesen, Liechtenstein.; Center of Laboratory Medicine, University Institute of Clinical Chemistry, University of Bern, Inselspital, 3010 Bern, Switzerland., Aeschbacher S; Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University of Basel, Spitalstrasse 2, 4056 Basel, Switzerland., Risch C; Labormedizinisches Zentrum Dr Risch, Wuhrstrasse 14, 9490 Vaduz, Liechtenstein., Weber MC; Landesspital Liechtenstein, Heiligkreuz, 9490 Vaduz, Liechtenstein., Thiel SL; Landesspital Liechtenstein, Heiligkreuz, 9490 Vaduz, Liechtenstein., Jüngert K; Landesspital Liechtenstein, Heiligkreuz, 9490 Vaduz, Liechtenstein., Pichler M; Landesspital Liechtenstein, Heiligkreuz, 9490 Vaduz, Liechtenstein., Grossmann K; Labormedizinisches Zentrum Dr Risch, Wuhrstrasse 14, 9490 Vaduz, Liechtenstein.; Faculty of Medical Sciences, Private Universität im Fürstentum Liechtenstein, Dorfstrasse 24, 9495 Triesen, Liechtenstein., Wohlwend N; Labormedizinisches Zentrum Dr Risch, Wuhrstrasse 14, 9490 Vaduz, Liechtenstein., Lung T; Labormedizinisches Zentrum Dr Risch, Wuhrstrasse 14, 9490 Vaduz, Liechtenstein., Hillmann D; Labormedizinisches Zentrum Dr Risch, Wuhrstrasse 14, 9490 Vaduz, Liechtenstein., Bigler S; Labormedizinisches Zentrum Dr Risch, Waldeggstrasse 37, 3097 Liebefeld, Switzerland., Bodmer T; Labormedizinisches Zentrum Dr Risch, Waldeggstrasse 37, 3097 Liebefeld, Switzerland., Imperiali M; Centro Medicina di Laboratorio Dr Risch, Via Arbostra 2, 6963 Pregassona, Switzerland., Renz H; Institute of Laboratory Medicine and Pathobiochemistry, Molecular Diagnostics, University Hospital Giessen and Marburg, Philipps University Marburg, Baldingerstraße, 35043 Marburg, Germany., Kohler P; Department of Infectious Diseases and Hospital Epidemiology, Cantonal Hospital St. Gallen, Rohrschacherstrasse 95, 9007 St. Gallen, Switzerland., Vernazza P; Department of Infectious Diseases and Hospital Epidemiology, Cantonal Hospital St. Gallen, Rohrschacherstrasse 95, 9007 St. Gallen, Switzerland., Kahlert CR; Department of Infectious Diseases and Hospital Epidemiology, Cantonal Hospital St. Gallen, Rohrschacherstrasse 95, 9007 St. Gallen, Switzerland.; Department of Infectious Diseases and Hospital Epidemiology, Children's Hospital of Eastern Switzerland, Claudiusstrasse 6, 9006 St. Gallen, Switzerland., Twerenbold R; Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University of Basel, Spitalstrasse 2, 4056 Basel, Switzerland.; Clinic of Cardiology, University Hospital Basel, Petersgraben 4, 4031 Basel, Switzerland., Paprotny M; Landesspital Liechtenstein, Heiligkreuz, 9490 Vaduz, Liechtenstein., Conen D; Population Health Research Institute, McMaster University, 237 Barton Street East, Hamilton, ON L8L 2X2, Canada., Risch M; Central Laboratory, Kantonsspital Graubünden, Loësstrasse 170, 7000 Chur, Switzerland. |
| Abstrakt: |
Pan-immunoglobulin assays can simultaneously detect IgG, IgM and IgA directed against the receptor binding domain (RBD) of the S1 subunit of the spike protein (S) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 S1-RBD Ig). In this work, we aim to evaluate a quantitative SARS-CoV-2 S1-RBD Ig electrochemiluminescence immunoassay (ECLIA) regarding analytical, diagnostic, operational and clinical characteristics. Our work takes the form of a population-based study in the principality of Liechtenstein, including 125 cases with clinically well-described and laboratory confirmed SARS-CoV-2 infection and 1159 individuals without evidence of coronavirus disease 2019 (COVID-19). SARS-CoV-2 cases were tested for antibodies in sera taken with a median of 48 days (interquartile range, IQR, 43-52) and 139 days (IQR, 129-144) after symptom onset. Sera were also tested with other assays targeting antibodies against non-RBD-S1 and -S1/S2 epitopes. Sensitivity was 97.6% (95% confidence interval, CI, 93.2-99.1), whereas specificity was 99.8% (95% CI, 99.4-99.9). Antibody levels linearly decreased from hospitalized patients to symptomatic outpatients and SARS-CoV-2 infection without symptoms ( p < 0.001). Among cases with SARS-CoV-2 infection, smokers had lower antibody levels than non-smokers ( p = 0.04), and patients with fever had higher antibody levels than patients without fever ( p = 0.001). Pan-SARS-CoV-2 S1-RBD Ig in SARS-CoV-2 infection cases significantly increased from first to second follow-up ( p < 0.001). A substantial proportion of individuals without evidence of past SARS-CoV-2 infection displayed non-S1-RBD antibody reactivities (248/1159, i.e., 21.4%, 95% CI, 19.1-23.4). In conclusion, a quantitative SARS-CoV-2 S1-RBD Ig assay offers favorable and sustained assay characteristics allowing the determination of quantitative associations between clinical characteristics (e.g., disease severity, smoking or fever) and antibody levels. The assay could also help to identify individuals with antibodies of non-S1-RBD specificity with potential clinical cross-reactivity to SARS-CoV-2. |
