Evaluation of anti-SARS-CoV-2 antibody levels: two different methods.

Aslan, Özgür; Mızraklı, Ayser; Aktar, Gülseren Samancı; Onur, Arzu Rahmanalı

OBJECTIVE Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease (COVID-19) is still a major problem worldwide. Antibody response to SARS-CoV-2 has not yet been fully clarified, and clinical benefits of serological tests remain unclear. Despite the presence of numerous systems and methods used to analyze antibody levels, it is difficult to mention about standardization. This study aims to evaluate antibody levels of COVID-19 patients obtained by different methods. METHODS Specimens of 55 patients were included in this study. Patients underwent SARS-CoV-2 real-time polymerase chain reaction test, COVID-19 IgM/IgG antibody rapid test (Hotgen), and Roche SARS-CoV-2 antibody test. RESULTS In this study, the positive values of COVID-19 IgM/IgG antibody rapid test, Roche SARS-CoV-2 antibody test, and SARS-CoV-2 real-time polymerase chain reaction test were 37, 26, and 31, respectively, whereas the negative values were 18, 29, and 24, respectively. A comparison of the results using χ² test revealed a significant difference among SARS-CoV-2 real-time polymerase chain reaction, COVID-19 IgM/IgG antibody rapid test (Hotgen), and Roche SARS-CoV-2 antibody test. CONCLUSIONS We recommend antibody testing in close contact tracing as well as in real-time polymerase chain reaction negative symptomatic subjects. Standardization is important as positive values show significant variations among antibody tests.