Comparison of the Luminex NxTAG respiratory pathogen panel and a multiplex in-house real-time PCR panel for the detection of respiratory viruses in symptomatic patients

Comparative Performance of the Luminex NxTAG Respiratory Pathogen Panel, GenMark eSensor Respiratory Viral Panel, and BioFire FilmArray Respiratory Panel

This study compares three of the most inclusive and widely used panels for respiratory syndromic testing in the United States, namely, Luminex NxTAG Respiratory Pathogen Panel (RPP), BioFire FilmArray Respiratory Panel (RP), and GenMark eSensor Respiratory Viral Panel (RVP). We compared the three assays using nasopharyngeal swab samples (n = 350) collected from symptomatic patients (n = 329) in the pre-coronavirus disease 2019 (COVID-19) era. There was no significant difference in the overall accuracies of BioFire and Luminex assays (P = 0.6171); however, significant differences were found between BioFire and GenMark (P = 0.0003) and between GenMark and Luminex (P = 0.0009). The positive percent agreement of the BioFire RP assay was 94.1%, compared to 97.3% for GenMark RVP and 96.5% for Luminex RPP. Overall negative percent agreement values were high for all three assays, i.e., 99.9% for BioFire and Luminex and 99.5% for GenMark. The three assays were equivalent for adenovirus, human metapneumovirus, influenza A, and respiratory syncytial virus. Increased false-positive results were seen with BioFire for the endemic coronaviruses and with GenMark for influenza B and the parainfluenza viruses.

IMPORTANCE Clinical laboratories have multiple choices when it is comes to syndromic respiratory testing. Here, the Luminex NxTAG RPP is compared to the BioFire FilmArray RP and GenMark eSensor RVP for overall and per-target accuracy. As new tests come to market, it is important to ascertain their performance characteristics, compared to other widely used in vitro diagnostic products.

Rapid and Point-of-Care Testing in Respiratory Tract Infections: An Antibiotic Guardian?

This is a narrative review on the potential of rapid and point-of-care microbiological testing in pneumonia patients, focusing particularly on hospital-acquired and ventilator-associated pneumonia, which have substantial mortality and diverse microbiology. This work is written from a United Kingdom perspective, but much of it is generalizable internationally. In a world where antimicrobial resistance is a major international threat, the use of rapid molecular diagnostics has great potential to improve both the management of pneumonia patients and the stewardship of antibiotics. Rapid tests potentially can distinguish patients with bacterial versus viral infection and can swiftly identify bacterial pathogens and their resistances. We seek to answer the question: “Can such tests be used as an antibiotic guardian?” Their availability at the bedside rather than in the laboratory should best ensure that results are swiftly used to optimize patient management but will raise new challenges, not the least with respect to maintaining quality control and microbiology/infection control input. A further challenge lies in assessing the degree of trust that treating clinicians will place in these molecular diagnostic tests, particularly when early de-escalation of antibiotic therapy is indicated.

Multiplexed detection and identification of respiratory pathogens using the NxTAG® respiratory pathogen panel

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NxTAG chemistry offers an easy workflow, low hands-on-time and scalable throughput.

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All post-extraction assay steps take place in a single, closed tube.

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Clinical performance of NxTAG RPP is comparable to that of the xTAG RVP assay.

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Analytical performance is also similar or better than xTAG and xTAG FAST assays.

The Luminex® NxTAG® Respiratory Pathogen Panel (NxTAG RPP) is an IVD-cleared assay for the simultaneous detection and identification of nucleic acids from 18 respiratory viruses and 2 (or 3 outside of the U.S.) atypical bacterial pathogens in nasopharyngeal swabs. Its scalability allows concurrent testing of up to 96 samples in a single batch. Nucleic acid extracted from 200 µL of raw specimen using the easyMAG® extractor is added directly to pre-plated, lyophilized bead reagents (LBRs), where multiplexed RT-PCR and hybridization to MagPlex-TAG™ microspheres occurs within a sealed reaction well using a single cycling program. Data acquisition is done on the MAGPIX® instrument which reads and sorts the reaction products directly from the sealed well following transfer of the assay plate from the thermal cycler. NxTAG is the newest innovation in bead-based nucleic acid chemistry developed by Luminex. Here we provide the detailed assay protocol and present data which describe the clinical and analytical performance characteristics of NxTAG RPP.

The GenMark ePlex®: another weapon in the syndromic arsenal for infection diagnosis

As one of the most recent additions to the syndromic testing landscape, the ePlex^® platform by GenMark Diagnostics is a system that combines the manufacturer's signature electrochemical detection technology with updated microfluidics, providing a new option for multiplex testing that is both rapid and requires minimal hands-on steps. In this review, we detail the ePlex platform and its current/future syndromic panels, with a particular focus on the respiratory pathogen panel - the platform's first assay to undergo clinical trials and receive regulatory approval in the USA. By keeping informed of these ever-expanding laboratory options, clinicians and microbiologists can stay positioned at the forefront of infectious disease diagnosis.

Laboratory Diagnosis of Respiratory Tract Infections in Children - the State of the Art

In the pediatric population, respiratory infections are the most common cause of physician visits. Although many respiratory illnesses are self-limiting viral infections that resolve with time and supportive care, it can be critical to identify the causative pathogen at an early stage of the disease in order to implement effective antimicrobial therapy and infection control. Over the last few years, diagnostics for respiratory infections have evolved substantially, with the development of novel assays and the availability of updated tests for newer strains of pathogens. Newer laboratory methods are rapid, highly sensitive and specific, and are gradually replacing the conventional gold standards, although the clinical utility of these assays is still under evaluation. This article reviews the current laboratory methods available for testing for respiratory pathogens and discusses the advantages and disadvantages of each approach.