Clinical comparison and agreement of PCR, antigen, and viral culture for the diagnosis of COVID-19: Clinical Agreement Between Diagnostics for COVID19

Amanda Agard; Omar Elsheikh; Drew Bell; Ryan F Relich; Bryan H Schmitt; Josh Sadowski; William Fadel; Douglas H Webb; Lana Dbeibo; Kristen Kelley; Mariel Carozza; Guang-Shen Lei; Paul Calkins; Cole Beeler

doi:10.1016/j.jcvp.2022.100099

Clinical comparison and agreement of PCR, antigen, and viral culture for the diagnosis of COVID-19: Clinical Agreement Between Diagnostics for COVID19

J Clin Virol Plus. 2022 Aug;2(3):100099. doi: 10.1016/j.jcvp.2022.100099. Epub 2022 Jul 21.

Authors

Affiliations

¹ Indiana University School of Medicine.
² Indiana University Health.
³ Indiana University Richard M. Fairbanks School of Public Health.
⁴ Genezen.

Abstract

The aim of this study is to compare the COVID-19 nasopharyngeal PCR (NP PCR) to antigen, nasal PCR, and viral culture. One-hundred-and-fourteen risk-stratified patients were tested by culture, nasal PCR, NP PCR, and Ag testing. Twenty (48%) of the high risk and 23 (32%) of the low risk were NP PCR positive. Compared with NP PCR, the sensitivity of nasal PCR, Sofia Ag, BinaxNOW Ag, and culture were 44%, 31%, 37%, and 15%. In the high risk group, the sensitivity of these tests improved to 71%, 37%, 50%, and 22%. Agreement between tests was highest between nasal PCR and both antigen tests. Patients who were NP PCR positive but antigen negative were more likely to have remote prior COVID-19 infection (p<0.01). Nasal PCR and antigen positive patients were more likely to have symptoms (p = 0.01).

Keywords: Antigen testing; COVID-19; Diagnostics; PCR testing; SARS-CoV-2; Viral culture.