Performance of Xpert Xpress SARS-Cov-2 assay for diagnosis of Covid-19 at a tertiary care center
Abstract
Introduction: The Expert Xpress SARS-Cov-2 assay is an automated real-time high-performance rapid PCR assay encompassing specimen processing, nucleic acid extraction, amplification and amplicon detection in a single cartridge. On March 20th 2020, it received an emergency authorization for use from the U.S. Food and Drug Administration for diagnosis of SARS-CoV-2.
Materials and Methods: This study was conducted in the virology section of Microbiology at Sher-i-Kashmir Institute of Medical Sciences from February to April 2023. A total of 73 nasopharyngeal samples that we received in our virology lab were subjected to RT-PCR and Xpert Xpress SARS-CoV-2 assay.
Results: Considering RT-PCR as the gold standard, the sensitivity of Xpert Xpress SARS-CoV-2 assay was 100%, specificity was 88.88%, positive predictive value was 96.49% and negative predictive value was 100%.
Conclusion: Based on the interpretation of our results, we find Xpert Xpress SARS-CoV-2 assay an excellent tool for diagnosis of COVID-19 especially in emergency cases and in situations where fewer samples need to be tested.
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References
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