COVID-19 Evidence Alerts
from McMaster PLUSTM

Current best evidence for clinical care (more info)

Diagnosis Pena-Rodriguez M, Viera-Segura O, Garcia-Chagollan M, et al. Performance evaluation of a lateral flow assay for nasopharyngeal antigen detection for SARS-CoV-2 diagnosis. J Clin Lab Anal. 2021 May;35(5):e23745. doi: 10.1002/jcla.23745. Epub 2021 Mar 5.
Abstract

BACKGROUND: SARS-CoV-2 has become a global pandemic due to its capacity for rapid transmission. In this context, an early and rapid diagnosis of infected patients that do not require expensive equipment or highly trained personnel is crucial in order to reduce the contagious rate. The aim of this study was to evaluate a chromatographic immunoassay's performance for the rapid diagnosis of SARS-CoV-antigen.

METHODS: A cross-sectional study included 369 adults from Western México with diagnosis or suspicion of SARS-CoV-2 infection. Two samples were collected; a naso-oropharyngeal was used for a molecular determination of SARS-CoV-2 RNA. The molecular analysis was carried out using DeCoV19 Kit Triplex (Genes2life S.A.P.I.) based on the CDC diagnostic panel for N1, N2, and N3 regions. The second sample was retrieved from a nasopharyngeal rub and used for the rapid diagnosis of SARS-CoV-2 antigen employing the commercial STANDARD™ Q COVID-19 Ag Test (SD BIOSENSOR).

RESULTS: Overall, in 28.2% of the patients was detected the SARS-CoV-2 RNA, and 21.4% were positive for antigen detection. The rapid antigen test showed a sensitivity and specificity of 75.9% and 100%, respectively, with a positive predictive and negative values of 100% and 91%. Symptoms as anosmia presented a high OR for the positive diagnosis for both test, reverse transcription-polymerase chain reaction (RT-PCR), and the rapid antigen test of 8.86 (CI = 4.91-16) and 6.09 (CI = 3.42-10.85), respectively.

CONCLUSION: SD BIOSENSOR is a useful assay, but some caveats must be considered before the general implementation.

Ratings
Discipline / Specialty Area Score
Public Health
Infectious Disease
Hospital Doctor/Hospitalists
Internal Medicine
Comments from MORE raters

Hospital Doctor/Hospitalists rater

Though RT-PCR tests are considered gold standard, Antigen tests are commonly used because of the ease of production and distribution, Their cost effectiveness can be especially useful in mass testing sites. Also it’s important to recognize their limitations and understand that they do not replace gold standard testing tools.

Public Health rater

The authors' conclusion (SD BIOSENSOR is a useful assay, but some caveats must be considered before the general implementation) is justified by the data collected.