Performance of a Rapid, Highly Multiplexed Nucleic Acid Detection Assay for Identification of Viral and Bacterial Pathogens from Upper Respiratory Tract Specimens.

Accurate and timely identification of upper respiratory tract pathogens can improve patient management by decreasing unnecessary additional testing, reducing the cost of care, and informing antimicrobial stewardship. We evaluated the FDA-cleared Diasorin LIAISON PLEX® Respiratory Flex (RSP Flex), a highly multiplexed, rapid nucleic acid detection assay that can identify 14 viral and 5 bacterial respiratory pathogens. In total, 215 residual patient upper respiratory tract specimens were tested using the RSP Flex assay and results compared to standard-of-care (SOC) molecular testing. Positive percentage agreement (PPA) was 100% for the following targets: adenovirus, human coronavirus, Bordetella pertussis, Bordetella parapertussis, Mycoplasma pneumoniae, and Chlamydia pneumoniae. Performance for the remaining panel targets were: human enterovirus/rhinovirus PPA = 97.5% (39/40), influenza A virus PPA = 92.3% (12/13), human metapneumovirus PPA = 87.5% (14/16), influenza B virus PPA = 92.9% (13/14), parainfluenza 1 virus PPA = 85.7% (6/7), parainfluenza 2 virus PPA = 80% (4/5), parainfluenza 3 virus PPA = 85.7% (12/14), parainfluenza 4 virus PPA = 87.5% (7/8), respiratory syncytial virus (RSV) PPA = 92.9% (13/14), and SARS-CoV-2 PPA = 95.0% (19/20). The negative percentage agreement (NPA) for all targets was 100% except adenovirus NPA = 98.4% (180/183), enterovirus/rhinovirus NPA = 96.9% (155/160), and M. pneumoniae NPA = 91.9% (34/37). For all targets, the RSP Flex assay had an overall PPA of 93.8%, NPA of 99.5% and complete concordance of 99.1% compared to SOC testing. The LIAISON PLEX RSP Flex assay is a fully automated, sample-to-customizable answer system that offers a wide range of bacterial and viral target testing with high accuracy.