Comparison between chemiluminescence and colloidal gold method in the detection of 2019 novel coronavirus specific antibodies and the value in COVID-19 diagnosis and treatment

ABSTRACT

Objective: To compare the chemiluminescence and colloidal gold method in the detection of 2019 novel Coronavirus (2019-nCoV, or SARS-CoV-2) specific antibody and to evaluate the importance in the diagnosis and treatment of COVID-19. Methods: A total of 191 cases of diagnosed and suspected COVID-19 patients admitted in Febrary 2020 in Wuhan Leishenshan Hospital were included. The patients were divided into 2019-nCoV continuous positive group, 2019-nCoV positive to negative group, and 2019-nCoV suspect group according to the results of pharyngeal swab 2019-nCoV nucleic acid detection. In addition, 27 patients without COVID-19 were set as control group to test the specificity. The serum samples were collected, and colloidal gold and chemiluminescence method were used to detect total antibodies (IgM+IgG) and IgM. SPSS 24.0 was used to compare the difference in antibody detection rates between the two methods. Results: The specificity of total antibodies (IgM+IgG) and IgM detection was 100%. Two methods of total antibody detection had no significant difference in continuous positive group (P=1.00). In positive to negative group and suspect group, the positive detection rate of chemiluminescence method was significantly higher than colloidal gold method (95.2% vs 76.2% and 94.9% vs 70.5%, respectively, both P0.05). The chemiluminescence method showed no significant difference between the three groups in IgM detection (P0.05). Conclusion: The detection of 2019-nCoV specific antibody can be an important supplemental method to pharyngeal swab 2019-nCoV nucleic acid detection during the diagnosis and treatment of COVID-19. The chemiluminescence method is better than colloidal gold method in the detection of total antibody. The IgM detection using chemiluminescence method is suitable for all stages of the disease. © 2020, Editorial Board of Medical Journal of Wuhan University. All right reserved.