Your browser doesn't support javascript.
Effect of urea dissociation on reducing the number of false-positive results of IgM and IgG antibodies against SARS-CoV -2
Chinese Journal of Virology ; 36(4):570-577, 2020.
Article in Chinese | GIM | ID: covidwho-1407616
ABSTRACT
We wished to explore the interference factors causing false-positive results for immunoglobulin M (IgM) and IgG antibodies in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detected by the gold immunochromatography assaym (GICA). In this way, we wanted to improve the detection method and scheme of laboratory detection. Seventy-four serum samples from outpatients and inpatients from the Affiliated Hospital of North Sichuan Medical College and Nanchong Central Hospital in China from 2 January 2020 to 5 March 2020 were collected 19 patients with the nucleic acids of SARS-CoV-2;10 cases with IgM antibodies against other respiratory viruses;10 patients with IgM antibodies against hepatitis viruses;20 patients with IgM antibodies against rheumatoid factor (RF);15 patients with antinuclear antibody (ANA). Colloidal GICA (kit A and kit B) was used to detect IgM and IgG antibodies against SARS-CoV-2 in patient sera. Positive results of SARS-CoV-2 IgM or SARS-CoV -2 IgG antibodies were analyzed, and possible factors causing false-positive results were found. Then, the sera of SARS- CoV - 2 IgM/IgG positive and 3 early coronavirus disease 2019 (COVID-19) patients were dissociated with an appropriate concentration of urea, and levels of IgM and IgG antibodies against SARS-CoV-2 were redetermined. SPSS v19.0 was used to analyze data. In the sera of 19 patients with SARS-CoV-2 infection 15 of SARS -CoV-2 IgM antibodies and 18 cases SARS-CoV-2 IgG antibodies were detected in kit A;12 cases of SARS-CoV-2 IgM antibodies and 12 cases of SARS-CoV-2 IgG antibodies were detected in kit B;16 cases of SARS-CoV-2 IgM antibodies and 14 cases of SARS-CoV -2 IgG antibodies were detected in 20 patients who had IgM antibodies against RF. In the sera of 15 patients with high - titer ANA, SARS-CoV- 2 IgG antibodies were detected in four cases using kit B. When the urea dissociation concentration was 2 mol/L, 14 of 16 RF- IgM - positive sera detected using kit A turned negative, 13 of 14 SARS- CoV- 2 IgG antibodies turned negative, but patients with COVID-19 detected by kit A did not show negative conversion of IgM or IgG antibodies. When the urea dissociation concentration was 4 mol/L, ANA -positive serum detected by kit B turned negative in four cases, whereas SARS-CoV-2 IgM and IgG antibodies in patients with COVID-19 did not turn negative. After urea dissociation, the SARS-CoV- 2 IgM antibodies detected by kit A and kit B in the sera of three patients with early COVID- 19 did not turn negative. RF could cause false-positive results for SARS-CoV-2 IgM and IgG antibodies detected by kit A, and a high titer of ANA could cause false-positive results of SARS-CoV-2 IgG antibodies detected by kit B. Urea dissociation could be helpful for reducing the probability of false-positive results of SARS-CoV-2 IgM and IgG antibodies. The effect of urea dissociation on the detection sensitivity of early COVID-19 merits further study.
Search on Google
Collection: Databases of international organizations Database: GIM Type of study: Experimental Studies Language: Chinese Journal: Chinese Journal of Virology Year: 2020 Document Type: Article

Similar

MEDLINE

...
LILACS

LIS

Search on Google
Collection: Databases of international organizations Database: GIM Type of study: Experimental Studies Language: Chinese Journal: Chinese Journal of Virology Year: 2020 Document Type: Article