2023 Volume 72 Issue 2 Pages 205-209
The gold standard to detect SARS-CoV-2 is reverse transcription-polymerase chain reaction (RT-PCR). We evaluated an automated quantitative antigen assay using the Elecsys SARS-CoV-2 antigen (Roche) to detect SARS-CoV-2. We tested 214 subjects, 130 (60.7%) of whom were positive in the molecular tests for SARS-CoV-2 infection using nasopharyngeal samples, with a SARS-CoV-2 RT-PCR kit and the quantitative antigen assay. The positive concordance rate was 85.4% and the negative concordance rate was 100%. The Ct value of quantitative RT-PCR showed an inverse correlation with the logarithmically transformed antigen quantitative value (r = 0.947). Results suggest that the quantitative antigen assay is a potentially useful surrogate test for the quantitative RT-PCR assay since it also showed an acceptable accuracy as a screening test. The automated antigen assay also allows fast turn-around times and a high throughput and might be useful in emergency care, adequate bed management, and so forth.
