Open AccessEvaluation of a novel, rapid antigen detection test for the diagnosis of SARS-CoV-2
Author(s) -
Rainer Thell,
Verena Kallab,
Wolfgang Weinhappel,
Wolfgang Mueckstein,
Lukas Heschl,
Martina Heschl,
Stefan Korsatko,
Franz Toedling,
Amelie Blaschke,
Theresa Herzog,
Anna Klicpera,
Clara Koeller,
Moritz Haugk,
Anna Kreil,
Alexander Spiel,
Philipp Kreuzer,
Robert Krause,
Christian Sebesta,
Stefan Winkler,
Brenda Laky,
Marton Széll
Publication year - 2021
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0259527
Subject(s) - medicine , covid-19 , point of care testing , predictive value , antigen , diagnostic test , gastroenterology , real time polymerase chain reaction , positive predicative value , reverse transcription polymerase chain reaction , prospective cohort study , disease , immunology , pediatrics , infectious disease (medical specialty) , gene , biology , messenger rna , biochemistry
Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing coronavirus disease 2019 (COVID-19) is currently finally determined in laboratory settings by real-time reverse-transcription polymerase-chain-reaction (rt-PCR). However, simple testing with immediately available results are crucial to gain control over COVID-19. The aim was to evaluate such a point-of-care antigen rapid test (AG-rt) device in its performance compared to laboratory-based rt-PCR testing in COVID-19 suspected, symptomatic patients. Methods For this prospective study, two specimens each of 541 symptomatic female (54.7%) and male (45.3%) patients aged between 18 and 95 years tested at five emergency departments (ED, n = 296) and four primary healthcare centres (PHC, n = 245), were compared, using AG-rt (positive/negative/invalid) and rt-PCR (positive/negative and cycle threshold, Ct) to diagnose SARS-CoV-2. Diagnostic accuracy, sensitivity, specificity, positive predictive values (PPV), negative predictive value (NPV), and likelihood ratios (LR+/-) of the AG-rt were assessed. Results Differences between ED and PHC were detected regarding gender, age, symptoms, disease prevalence, and diagnostic performance. Overall, 174 (32.2%) were tested positive on AG-rt and 213 (39.4%) on rt-PCR. AG correctly classified 91.7% of all rt-PCR positive cases with a sensitivity of 80.3%, specificity of 99.1%, PPV of 98.3, NPV of 88.6%, LR(+) of 87.8, and LR(-) of 0.20. The highest sensitivities and specificities of AG-rt were detected in PHC (sensitivity: 84.4%, specificity: 100.0%), when using Ct of 30 as cut-off (sensitivity: 92.5%, specificity: 97.8%), and when symptom onset was within the first three days (sensitivity: 82.9%, specificity: 99.6%). Conclusions The highest sensitivity was detected with a high viral load. Our findings suggest that AG-rt are comparable to rt-PCR to diagnose SARS-CoV-2 in COVID-19 suspected symptomatic patients presenting both at emergency departments and primary health care centres.