B-201 Clinical Performance Evaluation of IRON-qPCR™ RV, a Novel Molecular POCT system, for the Qualitative Detection of Respiratory Viruses in Nasopharyngeal Swab
Authors: Lee C , Lee J , Yang B , Kim T , Park H 
Published: October 2024

Abstract

Background
The availability of Point-of-Care testing (POCT) based on molecular diagnostics to test simultaneously for multiple respiratory viruses is very limited though significant progress has been made in molecular testing for COVID-19 during the pandemic. Considering the similar symptoms presented by patients infected with various respiratory pathogens, it is crucial to have multiple POCT systems capable of detecting multiple respiratory pathogens while distinguishing SARS-CoV-2 from other pathogens. To meet the growing demand for multiplex testing for respiratory pathogens, a molecular POCT, IRON-qPCR™ RV has been developed. IRfON-qPCR™ RV is a multiplex real-time RT-PCR assay designed for the qualitative detection and differentiation of SARS-CoV-2, Influenza A, Influenza B, RSV-A, and RSV-B RNA from human nasopharyngeal swab specimens. The IRON-qPCR™ proceeds the entire process automatically from nucleic acid extraction to real-time RT-PCR within 40 minutes. The main goal of this study is to evaluate the clinical performance of IRON-qPCR™ RV in comparison with other assays and kits using nasopharyngeal swab samples.

Methods
To assess the clinical performance of the IRON-qPCR™ RV, specimen collection and evaluation were conducted at a clinical institution in France, utilizing a total of 980 nasopharyngeal swab samples. The comparators used were the Xpert® Xpress CoV-2/Flu/RSV plus Kit and the RealStar® RSV RT-PCR Kit 3.0. Since RSV subtypes are not distinguished by the Xpert kit, all RSV without subtype distinction were compared. Additionally, RealStar kit was used to compare the results of IRON-qPCR™ RV for RSV subtypes A and B. Clinical samples showing discrepancies between Xpert and RealStart, and the IRON-qPCR™ RV were further analyzed using Allplex™ SARS-CoV-2/FuA/FluB/RSV Assay and sequencing.

Results
Through the comparison of clinical performance of the IRON-qPCR™ RV with Xpert for SARS-CoV-2, Influenza A, and Influenza B in nasopharyngeal swab samples, the clinical sensitivity was analyzed to be over 95.5%, and the clinical specificity was over 99.6%. For RSV, compared to Xpert, the clinical sensitivity was analyzed to be 96.9%, and the clinical specificity was 98.9%. Furthermore, in comparison with RealStar, the clinical sensitivity and specificity of IRON-qPCR™ RV for RSV-A were determined to be 96.2% and 100%, respectively, and the clinical sensitivity and specificity for RSV-B were 96.0% and 100%. Additionally, discrepant samples in comparison with Xpert were further tested using the Allplex as a resolver kit. The result showed that the clinical sensitivity and specificity of IRON-qPCR™ RV for SARS-CoV-2, Influenza A, and Influenza B were over 98.3% and 100%. For RSV, the clinical sensitivity and specificity were 99.5% and 99.1%.

Conclusions
The clinical performance of IRON-qPCR™ RV was analyzed with the clinical sensitivity of over 95% and the clinical specificity of over 99%. Upon analysis including the results of the resolver kit for discrepant samples, increased clinical sensitivity and specificity were determined. The results of this study strongly support that the IRON-qPCR™ RV is a reliable POCT system for the simultaneous detection and differentiation of multiple respiratory viruses. Furthermore, it is applicable to district hospitals as well as clinical laboratories for accurate and timely testing.