COVID-19 Evidence Alerts
from McMaster PLUSTM

Current best evidence for clinical care (more info)

Diagnosis Zhang ZL, Hou YL, Li DT, et al. Diagnostic efficacy of anti-SARS-CoV-2 IgG/IgM test for COVID-19: A meta-analysis. J Med Virol. 2020 Jun 22. doi: 10.1002/jmv.26211.
Abstract

The serological testing of anti-SARS-CoV-2 immunoglobulin G (IgG) and/or IgM is widely used in the diagnosis of COVID-19. However, its diagnostic efficacy remains unclear. In this study, we searched for diagnostic studies from the Web of Science, PubMed, Embase, CNKI, and Wanfang databases to calculate the pooled diagnostic accuracy measures using bivariate random-effects model meta-analysis. As a result, 22 from a total of 1613 articles, including 2282 patients with SARS-CoV-2 and 1485 healthy persons or patients without SARS-CoV-2, were selected for a meta-analysis. Pooled sensitivity, specificity, and area under curve of the summary receiver operator curve (SROC) were: (a) 0.85 (95% confidence interval [CI]: 0.79-0.90), 0.99 (95% CI: 0.98-1.00), and 0.99 (95% CI: 0.97-0.99) for anti-SARS-CoV-2 IgG and (b) 0.74 (95% CI: 0.65-0.81), 0.99 (95% CI: 0.97-1.00), and 0.95 (95% CI: 0.93-0.97) for IgM. A subgroup analysis among detection methods indicated the sensitivity of IgG and IgM using enzyme-linked immunosorbent assay were slightly lower than those using gold immunochromatography assay (GICA) and chemiluminescence immunoassay (P > .05). These results showed that the detection of anti-SARS-CoV-2 IgG and IgM had high diagnostic efficiency to assist the diagnosis of SARS-CoV-2 infection. And, GICA might be used as the preferred method for its accuracy and simplicity.

Ratings
Discipline / Specialty Area Score
General Internal Medicine-Primary Care(US)
Family Medicine (FM)/General Practice (GP)
Emergency Medicine
Respirology/Pulmonology
Public Health
Hospital Doctor/Hospitalists
Internal Medicine
Infectious Disease
Intensivist/Critical Care
Comments from MORE raters

Emergency Medicine rater

There is a great heterogeneity in the sensitivity of the tests, and the gold standard is not always strictly defined.

Family Medicine (FM)/General Practice (GP) rater

In the Quality Assessment section, 36.36% of studies were classified as high risk of bias where results were interpreted with knowledge of the RT-PCR. This should be concerning as interpretations of the IgG/IgM test are subjective, so a prior negative or positive result of the RT-PCR could lead to misreading results in this test. This point could be improved in later studies to conserve blinding. I find this information very useful and suitable for the current pandemic situation.

Hospital Doctor/Hospitalists rater

The review provides some basis for believing that serology results are meaningful in approaching COVID-19. It does not adequately address the critical question of "when" in a course if illness this should be used, and there are slight issues with the heterogeneity and methods around this. However, the core message is sound and worthwhile regarding the sensitivity and specificity of serology.

Infectious Disease rater

With the conflicting reports regarding the antibodies in simple serosurveys, the utility of antibodies in diagnosis is doubtful. This analysis of a heterogeneous group of a subgroup of patients, however, tries to establish evidence in diagnosis of COVID. This has to be confirmed in large studies and validated kits.

Infectious Disease rater

Althought is is useful information, it's unclear whether the results apply to recent or remote infections.

Public Health rater

Many studies had high risk of bias but were included in the meta-analysis. The authors describe the antibody test as diagnostic for COVID-19, but it can only identify infection after it has been in place. This field is moving very, very rapidly, updated reviews may provide better guidance regarding the role of antibody tests.

Public Health rater

This is very important review. The use of a comprehensive search and appraisal of the evidences are the strength of this review. The review showed that the detection of anti-SARS-CoV-2 IgG and IgM had high diagnostic efficiency to assist the diagnosis of SARS-CoV-2. It was suitable for patients with symptoms for at least 5 days. The use of this review in our daily practice is warranted.

Respirology/Pulmonology rater

This meta-analysis finds reassuring results that IgG and/or IgM antibodies are effective tools to detect or confirm a diagnosis of Covid-19.