A Comparison of Five SARS-CoV-2 Molecular Assays With Clinical Correlations. Issue 1 (5th October 2020)

• Record Type: Journal Article
• Authors: Procop, Gary W; Brock, Jay E; Reineks, Edmunds Z; Shrestha, Nabin K; Demkowicz, Ryan; Cook, Eleanor; Ababneh, Emad; Harrington, Susan M
• Is Part Of: American journal of clinical pathology. Volume 155:Issue 1(2021)
• Page Start: 69
• Page End: 78
• Publication Date: 2020-10-05
• Subjects: COVID-19 -- SARS-CoV-2 -- Nucleic acid amplification tests -- Coronavirus; Diagnosis, Laboratory -- Periodicals; Pathology -- Periodicals; 616.07
• DOI: 10.1093/ajcp/aqaa181
• Languages: English
• ISSNs: 0002-9173

Abstract

Abstract: Objectives: Comparative assessments of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) molecular assays that have been operationalized through the US Food and Drug Administration's Emergency Use Authorization process are warranted to assess real-world performance. Characteristics such as sensitivity, specificity, and false-negative rate are important to inform clinical use. Methods: We compared five SARS-CoV-2 assays using nasopharyngeal and nasal swab specimens submitted in transport media; we enriched this cohort for positive specimens, since we were particularly interested in the sensitivity and false-negative rate. Performance of each test was compared with a composite standard. Results: The sensitivities and false-negative rates of the 239 specimens that met inclusion criteria were, respectively, as follows: Centers for Disease Control and Prevention 2019 nCoV Real-Time RT-PCR Diagnostic Panel, 100% and 0%; TIB MOLBIOL/Roche z 480 Assay, 96.5% and 3.5%; Xpert Xpress SARS-CoV-2 (Cepheid), 97.6% and 2.4%; Simplexa COVID-19 Direct Kit (DiaSorin), 88.1% and 11.9%; and ID Now COVID-19 (Abbott), 83.3% and 16.7%. Conclusions: The assays that included a nucleic acid extraction followed by reverse transcription polymerase chain reaction were more sensitive than assays that lacked a full extraction. Most false negatives were seen in patients with low viral loads, as extrapolated from crossing threshold values.