Evaluation of fast-track diagnostics and TaqMan array card real-time PCR assays for the detection of respiratory pathogens

Abstract

Several commercial assays are now available to detect the nucleic acid of multiple respiratory pathogens from a single specimen. Head-to-head comparisons of such assays using a single set of standard specimens provide additional information about key assay parameters such as sensitivity, specificity and lower limits of detection, and help to inform the decision regarding which method to use. We evaluated two real-time PCR platforms: the Fast-track Diagnostics® (FTD) multiplex respiratory panel and a TaqMan array card (TAC) for simultaneous uniplex detection of multiple respiratory pathogens. Two sets of samples were used to evaluate the assays. One set was created by spiking pooled nasal wash or phosphate buffered saline with specified volumes of known concentrations of virus and/or bacteria. Clinical nasal wash specimens from children with lower respiratory tract illness comprised the other set. Thirteen pathogen targets were compared between the two platforms. Testing with a validation panel of spiked samples revealed a sensitivity of 96.1% and 92.9% for the FTD and TAC assays, respectively. Specificity could not be reliably calculated due to a suspected contamination of the sample substrate. Inter-assay agreement was high (> 95%) for most targets. Previously untested clinical specimens tested by both assays revealed a high percent agreement (> 95%) for all except rhinovirus, enterovirus and Streptococcus pneumoniae. Limitations of this evaluation included extraction of the validation samples by two different methods and the evaluation of the assays in different laboratories. However, neither of these factors significantly impacted inter-assay agreement for these sets of samples, and it was demonstrated that both assays could reliably detect clinically relevant concentrations of bacterial and viral pathogens.

Comparative analytical evaluation of the respiratory TaqMan Array Card with real-time PCR and commercial multi-pathogen assays

“…These platforms differ in a variety of features including the type and number of analyses that can be performed (viral, bacterial, mixed, influenza specific), detection technology and need for dedicated instrumentation, complexity, sensitivity and throughput, and cost per specimen. Comparative evaluations of several of these panels show that they all have good specificity and varying levels of sensitivity across pathogens (Sakthivel et al, 2012;Renaud et al, 2012;Popowitch et al, 2013;Babady et al, 2012;Gadsby et al, 2010;Rand et al, 2011;Driscoll et al, 2014). One common theme among all the commercial platforms is that the end user does not have control over the menu of assays included in the panel or the ability to customize individual assays without incurring significant developmental costs.…”

Multicenter evaluation of BD Veritor System and RSV K-SeT for rapid detection of respiratory syncytial virus in a diagnostic laboratory setting

“…The temperature profile used was 5 minutes 50°C; 20 seconds 95°C; 45 cycles composed of 3 seconds 95°C and 30 seconds 60°C. In the case of a PCR-negative result with both antigen tests positive, the PCR result was verified by a second RT-PCR method using a TaqMan array card (TAC, formerly TaqMan low-density array or TLDA) (Life Technologies, Carlsbad, CA, USA) (Driscoll et al, 2014).…”

Comparison of FTD® respiratory pathogens 33 and a singleplex CDC assay for the detection of respiratory viruses: A study from Cameroon

“…Viral culture, for example, can be time consuming, labor intensive and requires substantial technical expertise to maintain and evaluate cell culture monolayers (Leland and Ginocchio, 2007). Currently, nucleic acid amplification is the method of choice for the diagnosis of respiratory infections (Bierbaum et al, 2014;Driscoll et al, 2014;Kenmoe et al, 2016;Lagare et al, 2015;Malhotra et al, 2016). Molecular tests are widely recognized to contribute to a better efficiency, sensitivity and speed compared to traditional methods for the diagnosis of respiratory infections.…”

“…Recently, several multiplex rRT-PCR commercial methods have become available for the detection of respiratory pathogens (Anderson et al, 2013;Barratt et al, 2017;Driscoll et al, 2014;Malhotra et al, 2016). At this time, multiplex panels capable of simultaneously detecting more than three respiratory pathogens are widely available: Luminex NxTAG® Respiratory Pathogen Panel (Luminex Molecular Diagnostics, Austin, TX), FilmArray® Respiratory Panel (Biofire Diagnostics, Salt Lake City, UT), Allplex and Anyplex Respiratory Virus Panel Assays (Seegene), RespFinder® SMART and 2SMART (Patho Finder), Respiratory Multi Well System MWS r-gene® Range (BioMerieux) and Fast-Track Diagnostics FTD-21, -21+ & -33 (FTD®).…”

“…The introduction of these new multiplex methods allows the analysis of a wider range of respiratory pathogens coupled with simplification of procedures, reducing time to detection, sample volume requirements and risk of contamination. A number of studies have compared the performance of FTD® Respiratory Pathogens kits with that of in house respiratory panels or commercial panels, such as Luminex NxTAG® Respiratory Pathogen Panel (Luminex Molecular Diagnostics, Austin, TX), TaqMan Array Card® (Thermo Fischer Scientific) and Anyplex® Respiratory Virus Panel Assays (Seegene) (Anderson et al, 2013;Barratt et al, 2017;Bierbaum et al, 2014;Driscoll et al, 2014;Malhotra et al, 2016;Sakthivel et al, 2012). Overall, these reports showed that FTD® Respiratory Pathogens kits yield similar results as other multiplex pathogen detection kits.…”