Evaluation of Lumipulse® G SARS-CoV-2 antigen assay automated test for detecting SARS-CoV-2 nucleocapsid protein (NP) in nasopharyngeal swabs for community and population screening

• Published in: International journal of infectious diseases Vol. 105; pp. 391 - 396
• Main Authors: Gili, Alessio, Paggi, Riccardo, Russo, Carla, Cenci, Elio, Pietrella, Donatella, Graziani, Alessandro, Stracci, Fabrizio, Mencacci, Antonella
• Format: Journal Article
• Language: English
• Published: Canada Elsevier Ltd 01.04.2021; The Authors. Published by Elsevier Ltd on behalf of International Society for Infectious Diseases; Elsevier
• Subjects: Antigen NP; COVID-19; Diagnosis; Lumipulse; SARS-CoV-2; Screening; COVID-19; Screening; SARS-CoV-2; Lumipulse; Diagnosis; Antigen NP
• ISSN: 1201-9712; 1878-3511; 1878-3511
• DOI: 10.1016/j.ijid.2021.02.098

•The Lumipulse® SARS-CoV-2 antigen assay can be safely employed in screening strategies in small and large communities and in the general population.•At a 1.645 pg/mL optimal cutoff, the antigen test and RT-PCR overall agreement was 95.1% (1652/1738) and AUC was 97.4%; sensitivity and NPV were 100%.•The Lumipulse® G SARS-CoV-2 antigen assay is completely automated, faster and less expensive than RT-PCR. To compare the Lumipulse® SARS-CoV-2 antigen test with the gold standard real-time reverse transcription-polymerase chain reaction (RT-PCR) for diagnosis of SARS-CoV-2 infection and to evaluate its role in screening programs. Lumipulse® SARS-CoV-2 antigen assay was compared with the gold standard RT-PCR test in a selected cohort of 226 subjects with suspected SARS-CoV-2 infection, and its accuracy was evaluated. Subsequently, the test was administered to a real-life screening cohort of 1738 cases. ROC analysis was performed to explore test features and cutoffs. All tests were performed in the regional reference laboratory in Umbria, Italy. A 42.0% positive result at RT-PCR was observed in the selected cohort. The Lumipulse® system showed 92.6% sensitivity (95% CI 85.4–97.0%) and 90.8% specificity (95% CI 84.5–95.2%) at 1.24 pg/mL optimal cutoff. In the screening cohort, characterized by 5.2% prevalence of infection, Lumipulse® assay showed 100% sensitivity (95% CI 96.0–100.0%) and 94.8% specificity (95% CI 93.6–95.8%) at 1.645 pg/mL optimal cutoff; the AUC was 97.4%, NPV was 100% (95% CI 99.8–100.0%) and PPV was 51.1% (95% CI 43.5–58.7%). The Lumipulse® SARS-CoV-2 antigen assay can be safely employed in the screening strategies in small and large communities and in the general population.