Tweet
Am J Clin Pathol
. 2021 Apr 26;aqab033.
doi: 10.1093/ajcp/aqab033. Online ahead of print.
Unexpected False-Positive Rates in Pediatric SARS-CoV-2 Serology Using the EUROIMMUN Anti-SARS-CoV-2 ELISA IgG Assay
Daniel Geisler 1 , Megan Culler Freeman 2 , Glenn J Rapsinski 2 3 , Sarah E Wheeler 4
Affiliations
- PMID: 33899091
- DOI: 10.1093/ajcp/aqab033
Abstract
Objectives: Serologic assay performance studies for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-?2) in pediatric populations are lacking, and few seroprevalence studies have routinely incorporated orthogonal testing to improve accuracy.
Methods: Remnant serum samples for routine bloodwork from 2,338 pediatric patients at UPMC Children's Hospital of Pittsburgh were assessed using the EUROIMMUN Anti-SARS-CoV-2 ELISA IgG (EuroIGG) assay. Reactive cases with sufficient volume were also tested using 3 additional commercial assays.
Results: Eighty-five specimens were reactive according to the EuroIGG, yielding 3.64% (95% confidence interval [CI], 2.91%-4.48%) seropositivity, of which 73 specimens had sufficient remaining volume for confirmation by orthogonal testing. Overall, 19.18% (95% CI, 10.18%-28.18%) of samples were positive on a second and/or third orthogonal assay. This 80.82% false positivity rate is disproportionate to the expected false positivity rate of 50% given our pediatric population prevalence and assay performance.
Conclusions: In pediatric populations, false-positive SARS-CoV-2 serology may be more common than assay and prevalence parameters would predict, and further studies are needed to establish the performance of SARS-CoV-2 serology in children.
Keywords: Orthogonal testing; Pediatric population; SARS-CoV-2; Seroprevalence.