Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Apr 15;12(4):1348-1354.
eCollection 2020.

Clinical Evaluation of a Rapid Colloidal Gold Immunochromatography Assay for SARS-Cov-2 IgM/IgG

Affiliations
Free PMC article

Clinical Evaluation of a Rapid Colloidal Gold Immunochromatography Assay for SARS-Cov-2 IgM/IgG

Bo Shen et al. Am J Transl Res. .
Free PMC article

Abstract

Background: Since December 2019, there had been an outbreak of COVID-19 in Wuhan, China. At present, diagnosis COVID-19 were based on real-time RT-PCR, which have to be performed in biosafe laboratory and is unsatisfactory for suspect case screening. Therefore, there is an urgent need for rapid diagnostic test for COVID-19.

Objective: To evaluate the diagnostic performance and clinical utility of the colloidal gold immunochromatography assay for SARS-Cov-2 specific IgM/IgG anti-body detection in suspected COVID-19 cases.

Methods: In the prospective cohort, 150 patients with fever or respiratory symptoms were enrolled in Taizhou Public Health Medical Center, Taizhou Hospital, Zhejiang province, China, between January 20 to February 2, 2020. All patients were tested by the colloidal gold immunochromatography assay for COVID-19. At least two samples of each patient were collected for RT-PCR assay analysis, and the PCR results were performed as the reference standard of diagnosis. Meanwhile 26 heathy blood donor were recruited. The sensitivity and specificity of the immunochromatography assay test were evaluated. Subgroup analysis were performed with respect to age, sex, period from symptom onset and clinical severity.

Results: The immunochromatography assay test had 69 positive result in the 97 PCR-positive cases, achieving sensitivity 71.1% [95% CI 0.609-0.797], and had 2 positive result in the 53 PCR-negative cases, achieving specificity 96.2% [95% CI 0.859-0.993]. In 26 healthy donor blood samples, the immunochromatography assay had 0 positive result. In subgroup analysis, the sensitivity was significantly higher in patients with symptoms more than 14 days 95.2% [95% CI 0.741-0.998] and patients with severe clinical condition 86.0% [95% CI 0.640-0.970].

Conclusions: The colloidal gold immunochromatography assay for SARS-Cov-2 specific IgM/IgG anti-body had 71.1% sensitivity and 96.2% specificity in this population, showing the potential for a useful rapid diagnosis test for COVID-19. Further investigations should be done to evaluate this assay in variety of clinical settings and populations.

Keywords: COVID-19; immunoglobulin M/immunoglobulin G; rapid diagnosis.

Conflict of interest statement

None.

Figures

Figure 1
Figure 1
Flow of enrolled suspected COVID-19 patients. Abbreviation: COVID-19 = Coronavirus disease-19.
Figure 2
Figure 2
The colloidal gold immunochromatography results and interpretation. The appearance of two lines indicates a positive result, whereas a valid negative test produces only the control line. Intensity of antibody: 0=IgM/IgG negative, 1=IgM/IgG weakly positive(±), 2=IgM/IgG +, 3=IgM/IgG ++, 4=IgM/IgG +++.
Figure 3
Figure 3
Sensitivities of immunochromatography assay in different subgroups. Abbreviation: CI = confidence interval.
Figure 4
Figure 4
Time of seroconversion from onset of symptoms in patients infected with COVID-19. A. Scatter diagram of antibody level distribution in 28 patients one day before discharge. B. Seroconversion in patients 1, 2, 3. C. Appearing time of IgM/IgG. Intensity of antibody: 0=IgM/IgG negative, 1=IgM/IgG weakly positive(±), 2=IgM/IgG +, 3=IgM/IgG ++, 4=IgM/IgG +++. P<0.05 was considered statistically significant. Abbreviation: COVID-19 = Coronavirus disease-19.

Similar articles

See all similar articles

LinkOut - more resources

Feedback