Evaluation of three rapid lateral flow antigen detection tests for the diagnosis of SARS-CoV-2 infection

AbstractIntroductionThe COVID-19 pandemic has led to high demand of diagnostic tools. Rapid antigen detection tests have been developed and many have received regulatory acceptance such as CE IVD or FDA markings. Their performance needs to be carefully assessed.Materials and Methods158 positive and 40 negative retrospective samples collected in saline and analyzed by a laboratory-developed RT-PCR test were used to evaluate Sofia (Quidel), Standard Q (SD Biosensor), and Panbio™ (Abbott) rapid antigen detection tests (RADTs). A subset of the specimens was subjected to virus culture.ResultsThe specificity of all RADTs was 100% and the sensitivity and percent agreement was 80% and 85% for Sofia, 81% and 85% for Standard Q, and 83% and 86% for Panbio™, respectively. All three RADTs evaluated in this study reached a more than 90% sensitivity for samples with a high viral load as estimated from the low Ct values in the reference RT-PCR. Virus culture was successful in 80% of specimens with a Ct value <25.ConclusionsAs expected, the RADTs were less sensitive than RT-PCR. However, they benefit from the speed and ease of testing, and lower price as compared to RT-PCR. Repeated testing in appropriate settings may improve the overall performance.

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Rapid SARS-CoV-2 antigen detection assay in comparison with real-time RT-PCR assay for laboratory diagnosis of COVID-19 in Thailand

Virology Journal ◽

10.1186/s12985-020-01452-5 ◽

2020 ◽

Vol 17 (1) ◽

Cited By ~ 3

Author(s):

Chutikarn Chaimayo ◽

Bualan Kaewnaphan ◽

Nattaya Tanlieng ◽

Niracha Athipanyasilp ◽

Rujipas Sirijatuphat ◽

...

Keyword(s):

Real Time ◽

Sensitivity And Specificity ◽

False Negative ◽

Laboratory Diagnosis ◽

Antigen Detection ◽

Rt Pcr ◽

Pcr Assay ◽

Screening Assay ◽

The Real ◽

Pcr Test

Abstract Background The Coronavirus disease 2019 (COVID-19) pandemic continues to spread across the world. Hence, there is an urgent need for rapid, simple, and accurate tests to diagnose severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Performance characteristics of the rapid SARS-CoV-2 antigen detection test should be evaluated and compared with the gold standard real-time reverse transcription-polymerase chain reaction (RT-PCR) test for diagnosis of COVID-19 cases. Methods The rapid SARS-CoV-2 antigen detection test, Standard™ Q COVID-19 Ag kit (SD Biosensor®, Republic of Korea), was compared with the real-time RT-PCR test, Allplex™ 2019-nCoV Assay (Seegene®, Korea) for detection of SARS-CoV-2 in respiratory specimens. Four hundred fifty-four respiratory samples (mainly nasopharyngeal and throat swabs) were obtained from COVID-19 suspected cases and contact individuals, including pre-operative patients at Siriraj Hospital, Bangkok, Thailand during March–May 2020. Results Of 454 respiratory samples, 60 (13.2%) were positive, and 394 (86.8%) were negative for SARS-CoV-2 RNA by real-time RT-PCR assay. The duration from onset to laboratory test in COVID-19 suspected cases and contact individuals ranged from 0 to 14 days with a median of 3 days. The rapid SARS-CoV-2 antigen detection test’s sensitivity and specificity were 98.33% (95% CI, 91.06–99.96%) and 98.73% (95% CI, 97.06–99.59%), respectively. One false negative test result was from a sample with a high real-time RT-PCR cycle threshold (Ct), while five false positive test results were from specimens of pre-operative patients. Conclusions The rapid assay for SARS-CoV-2 antigen detection showed comparable sensitivity and specificity with the real-time RT-PCR assay. Thus, there is a potential use of this rapid and simple SARS-CoV-2 antigen detection test as a screening assay.

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Utility of Repeat Nasopharyngeal SARS-CoV-2 RT-PCR Testing and Refinement of Diagnostic Stewardship Strategies at a Tertiary Care Academic Center in a Low-Prevalence Area of the United States

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa388 ◽

2020 ◽

Vol 7 (9) ◽

Author(s):

Alexander J Lepak ◽

Derrick J Chen ◽

Ashley Buys ◽

Linda Stevens ◽

Nasia Safdar

Keyword(s):

Demographic Data ◽

Tertiary Care ◽

False Negative ◽

The United States ◽

Inpatient Setting ◽

Repeated Testing ◽

Rt Pcr ◽

Academic Center ◽

Low Prevalence ◽

Pcr Test

Abstract Background Multiple factors have led to an extremely high volume of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcription polymerase chain reaction (RT-PCR) testing. Concerns exist about sensitivity and false-negative SARS-CoV-2 RT-PCR testing results. We describe a retrospective observational study examining the utility of repeat nasopharyngeal (NP) SARS-CoV-2 RT-PCR testing at an academic center in a low-prevalence setting. Methods All patients within our health system with >1 NP SARS-CoV-2 RT-PCR test result were included. SARS-CoV-2 RT-PCR testing was performed according to 1 of 4 validated assays. Key clinical and demographic data were collected, including whether the patient was inpatient or outpatient at time of the test and whether the test was performed as part of a person under investigation (PUI) for possible coronavirus disease 2019 or for asymptomatic screening. Results A total of 660 patients had >1 NP SARS-CoV-2 PCR test performed. The initial test was negative in 638. There were only 6 negative-to-positive conversions (0.9%). All 6 were outpatients undergoing a PUI workup 5–17 days after an initial negative result. In >260 inpatients with repeat testing, we found no instances of negative-to-positive conversion including those undergoing PUI or asymptomatic evaluation. Conclusions In a low-prevalence area, repeat inpatient testing after an initial negative result, using a highly analytically sensitive SARS-CoV-2 RT-PCR, failed to demonstrate negative-to-positive conversion. The clinical sensitivity of NP RT-PCR testing may be higher than previously believed. These results have helped shape diagnostic stewardship guidelines, in particular guidance to decrease repeated testing in the inpatient setting to optimize test utilization and preserve resources.

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Can a ‘3-tier Screening’ Strategy be Adopted during COVID-19 Pandemic for Safer Air Travel and to Help Curb its Spread Across Borders?

The Open COVID Journal ◽

10.2174/2666958702101010062 ◽

2021 ◽

Vol 1 (1) ◽

pp. 62-64

Author(s):

Mohammad Shahid

Keyword(s):

Detection Method ◽

Screening Strategy ◽

Air Travel ◽

Antigen Detection ◽

Destination Country ◽

Rt Pcr ◽

Screening Protocol ◽

Entire World ◽

Pcr Test

Since the appearance of SARS-CoV-2 in 2019, it spread quickly crossing geographical borders and thus affected almost the entire world. It was alarming to note its quick spread, which obviously was due to the increased frequency and ease of air travel in this era. Currently, many airlines (and countries too) have a prerequisite to have a negative COVID-19 RT-PCR test within 72 hrs. prior to boarding the flight. Although all the necessary precautions are strictly enforced during air travel, there is still a possibility that a person with a negative COVID-19 test (RT-PCR) around 72hrs prior to boarding the flight would have an infection and that the person would pass it on to fellow passengers on board and thus can further spread SARS-CoV-2 infection into the community if robust action is not initiated. There is also a subconscious apprehension among the passengers that co-passengers may have an infection on board. This is especially worrisome seeing the appearance of new variants recently. Here I present the logistics for a ‘3-tier screening’ protocol (1st test by RT-PCR within 72hrs of the flight schedule, 2nd test by rapid antigen detection method 1-5hrs prior to flight schedule, 3rd test post-arrival or to follow the destination country post-arrival protocol), which would at least provide an extra filter to separate the recently identified positive cases and thus prevent the spread of this threatening disease across the borders.

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Retrospective analysis of the performance of the SARS-CoV-2 rapid antigen detection test compared to the reference RT-PCR test

Annales de biologie clinique ◽

10.1684/abc.2021.1641 ◽

2021 ◽

Vol 79 (2) ◽

pp. 168-175

Author(s):

Mathieu Bernard ◽

Gina Cosentino ◽

Laura Pieri ◽

Pierre Zachary ◽

Michael Buser ◽

...

Keyword(s):

Retrospective Analysis ◽

Antigen Detection ◽

Rt Pcr ◽

Rapid Antigen Detection Test ◽

Pcr Test

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A comparative study: Results of rapid antigen detection assay and real time RT-PCR for diagnosis of COVID-19 in a tertiary care hospital

10.17727/jmsr.2020/8s1-4 ◽

2020 ◽

Vol 8 (S1) ◽

pp. 33-40

Author(s):

Banerjee J ◽

Reddy SG ◽

Darapuneni RC ◽

Bilolikar AK

Keyword(s):

Real Time ◽

Tertiary Care ◽

Antigen Detection ◽

Diagnostic Tools ◽

Nasopharyngeal Swab ◽

Care Hospital ◽

Rt Pcr ◽

Rapid Antigen Detection Test ◽

Detection Assay ◽

Study Results

Introduction: December 2019, witnessed the emergence of a novel coronavirus in human population. Later named as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has since spread across the globe and results into coronavirus disease 2019 (COVID-19) pandemic. Objective: The objective of this study was to evaluate COVID-19 infection positivity rate, its age and gender wise prevalence and to compare the results of rapid antigen detection test with gold standard real time RT-PCR for early detection of SARS-CoV-2 virus. Methods: An observational study was conducted in the Department of Microbiology and Molecular Biology of Krishna Institute of Medical Sciences, Secunderabad, Telangana. Results: A total of 208 patients’ specimens (nasopharyngeal swab) were compared within a period of one and half month. Infection positivity rate was observed as 26.92% (n=56). Our study revealed that among all 56 COVID-19 positive patients, 60.71% (n=34) were symptomatic whereas 39.2% (n=22) were asymptomatic. Conclusion: We conclude that after comparing with real time RT-PCR, antigen detection assay is not as sensitive as molecular test especially during the early stages of infection but this has potential to become an important tool for mass screening for COVID-19 and can be considered as fast and economic diagnostic tools in the remote areas where the laboratory facilities for molecular tests are not accessible. Keywords: COVID-19; pandemic; nasopharyngeal swab; rapid antigen detection assay; real time RT-PCR

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Lumipulse G SARS-CoV-2 Ag Assay Evaluation for SARS-CoV-2 Antigen Detection Using 594 Nasopharyngeal Swab Samples from Different Testing Groups

10.1101/2021.01.26.21250533 ◽

2021 ◽

Author(s):

Giulia Menchinelli ◽

Licia Bordi ◽

Flora Marzia Liotti ◽

Ivana Palucci ◽

Maria Rosaria Capobianchi ◽

...

Keyword(s):

Positive Result ◽

Limit Of Detection ◽

False Negative ◽

Antigen Detection ◽

Nasopharyngeal Swab ◽

Repeated Testing ◽

Rt Pcr ◽

Subgenomic Rna ◽

Negative Results ◽

Percent Agreement

ABSTRACTCompared to RT-PCR, lower performance of antigen detection assays, including the Lumipulse G SARS-CoV-2 Ag assay, may depend on specific testing scenarios. We tested 594 nasopharyngeal swab samples from individuals with COVID-19 (RT-PCR cycle threshold [Ct] values ≤40) or non-COVID-19 (Ct values ≤40) diagnoses. RT-PCR positive samples were assigned to diagnostic, screening, or monitoring groups of testing. With a limit of detection of 1.2 × 104 SARS-CoV-2 RNA copies/ml, Lumipulse showed positive percent agreement (PPA) of 79.9% (155/194) and negative percent agreement of 99.3% (397/400), whereas PPAs were 100% for samples with Ct values of <18 or 18–<25 and 92.5% for samples with Ct values of 25–<30. By three groups, Lumipulse showed PPA of 87.0% (60/69), 81.1% (43/53), or 72.2% (52/72), respectively, whereas PPA was 100% for samples with Ct values of <18 or 18–<25, and was 94.4%, 80.0%, or 100% for samples with Ct values of 25–<30, respectively. RT-PCR positive samples were also tested for SARS-CoV-2 subgenomic RNA and, by three groups, testing showed that PPA was 63.8% (44/69), 62.3% (33/53), or 33.3% (24/72), respectively. PPAs dropped to 55.6%, 20.0%, or 41.7% for samples with Ct values of 25–<30, respectively. All 101 samples with a subgenomic RNA positive result had a Lumipulse assay’s antigen positive result, whereas only 54 (58.1%) of remaining 93 samples had a Lumipulse assay’s antigen positive result. In conclusion, Lumipulse assay was highly sensitive in samples with low RT-PCR Ct values, implying repeated testing to reduce consequences of false-negative results.

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Current challenges in COVID-19 diagnosis: a narrative review and implications for clinical practice

Italian Journal of Medicine ◽

10.4081/itjm.2021.1474 ◽

2021 ◽

Vol 15 (3) ◽

Author(s):

Gabriella Nucera ◽

Francesco Chirico ◽

Valentina Raffaelli ◽

Pietro Marino

Keyword(s):

Clinical Diagnosis ◽

Screening Tool ◽

Narrative Review ◽

Diagnostic Tools ◽

Quantitative Detection ◽

Lower Sensitivity ◽

Imaging Features ◽

Rt Pcr ◽

Epidemiological Surveys ◽

Pcr Test

Early diagnosis of coronavirus disease 2019 (COVID-19) is crucial to early treatment and quarantine measures. In this narrative review, diagnostic tools for COVID-19 diagnosis and their main critical issues were reviewed. The COVID-19 real-time reverse transcriptase-polymerase chain reaction (RT-PCR) test is considered the gold standard test for the qualitative and quantitative detection of viral nucleic acid. In contrast, tests can be used for epidemiological surveys on specific communities, including occupational cohorts, but not for clinical diagnosis as a substitute for swab tests. Computed tomography (CT) scans can be useful for the clinical diagnosis of COVID-19, especially in symptomatic cases. The imaging features of COVID-19 are diverse and depend on the stage of infection after the onset of symptoms. CT sensitivity seems to be higher in patients with positive RT-PCR. Conventional chest sensitivity shows a lower sensitivity. An important diagnostic screening tool is ultrasounds, whose specificity and sensitivity depend on disease severity, patient weight, and operator skills. Nevertheless, ultrasounds could be useful as a screening tool in combination with clinical features and molecular testing to monitor disease progression. Clinical symptoms and non-specific laboratory findings may be useful if used in combination with RT-PCR test and CT-scanning.

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From more testing to smart testing: data-guided SARS-CoV-2 testing choices

10.1101/2020.10.13.20211524 ◽

2020 ◽

Cited By ~ 9

Author(s):

Janko van Beek ◽

Zsofia Igloi ◽

Timo Boelsums ◽

Ewout Fanoy ◽

Hannelore Gotz ◽

...

Keyword(s):

Detection Limits ◽

Antigen Detection ◽

Rt Pcr ◽

Routine Testing ◽

Depth Analysis ◽

Testing Data ◽

Fit For Purpose ◽

Testing Algorithms ◽

Virus Culture

AbstractWe present an in-depth analysis of data from drive through testing stations using rapid antigen detection tests (RDT’s), RT-PCR and virus culture, to assess the ability of RDT’s to detect infectious cases. We show that the detection limits of five commercially available RDT’s differ considerably, impacting the translation into the detection of infectious cases. We recommend careful fit-for-purpose testing before implementation of antigen RDT’s in routine testing algorithms as part of the COVID-19 response.

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FGFR3 overexpression is a useful detection tool for FGFR3 fusions and sequence variations in glioma

Neuro-Oncology Practice ◽

10.1093/nop/npaa075 ◽

2020 ◽

Author(s):

Jens Schittenhelm ◽

Lukas Ziegler ◽

Jan Sperveslage ◽

Michel Mittelbronn ◽

David Capper ◽

...

Keyword(s):

Coiled Coil ◽

Growth Factor Receptor ◽

Gene Mutations ◽

Diagnostic Tools ◽

Wild Type ◽

Rt Pcr ◽

Fgfr3 Gene ◽

Detection Tool ◽

Sequence Variations ◽

Gene Panel Sequencing

Abstract Background Fibroblast growth factor receptor (FGFR) inhibitors are currently used in clinical development. A subset of glioblastomas carries gene fusion of FGFR3 and transforming acidic coiled-coil protein 3. The prevalence of other FGFR3 alterations in glioma is currently unclear. Methods We performed RT-PCR in 101 glioblastoma samples to detect FGFR3-TACC3 fusions (“RT-PCR cohort”) and correlated results with FGFR3 immunohistochemistry (IHC). Further, we applied FGFR3 IHC in 552 tissue microarray glioma samples (“TMA cohort”) and validated these results in two external cohorts with 319 patients. Gene panel sequencing was carried out in 88 samples (“NGS cohort”) to identify other possible FGFR3 alterations. Molecular modeling was performed on newly detected mutations. Results In the “RT-PCR cohort,” we identified FGFR3-TACC3 fusions in 2/101 glioblastomas. Positive IHC staining was observed in 73/1024 tumor samples of which 10 were strongly positive. In the “NGS cohort,” we identified FGFR3 fusions in 9/88 cases, FGFR3 amplification in 2/88 cases, and FGFR3 gene mutations in 7/88 cases in targeted sequencing. All FGFR3 fusions and amplifications and a novel FGFR3 K649R missense mutation were associated with FGFR3 overexpression (sensitivity and specificity of 93% and 95%, respectively, at cutoff IHC score > 7). Modeling of these data indicated that Tyr647, a residue phosphorylated as a part of FGFR3 activation, is affected by the K649R mutation. Conclusions FGFR3 IHC is a useful screening tool for the detection of FGFR3 alterations and could be included in the workflow for isocitrate dehydrogenase (IDH) wild-type glioma diagnostics. Samples with positive FGFR3 staining could then be selected for NGS-based diagnostic tools.

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Superiority of MALDI-TOF Mass Spectrometry over Real-Time PCR for SARS-CoV-2 RNA Detection

Viruses ◽

10.3390/v13050730 ◽

2021 ◽

Vol 13 (5) ◽

pp. 730

Author(s):

Magda Rybicka ◽

Ewa Miłosz ◽

Krzysztof Piotr Bielawski

Keyword(s):

Mass Spectrometry ◽

Gold Standard ◽

Viral Genome ◽

False Negative ◽

Rt Pcr ◽

Rna Detection ◽

Maldi Tof ◽

Negative Results ◽

False Negative Results ◽

Pcr Test

At present, the RT-PCR test remains the gold standard for early diagnosis of SARS-CoV-2. Nevertheless, there is growing evidence demonstrating that this technique may generate false-negative results. Here, we aimed to compare the new mass spectrometry-based assay MassARRAY® SARS-CoV-2 Panel with the RT-PCR diagnostic test approved for clinical use. The study group consisted of 168 suspected patients with symptoms of a respiratory infection. After simultaneous analysis by RT-PCR and mass spectrometry methods, we obtained discordant results for 17 samples (10.12%). Within fifteen samples officially reported as presumptive positive, 13 were positive according to the MS-based assay. Moreover, four samples reported by the officially approved RT-PCR as negative were positive in at least one MS assay. We have successfully demonstrated superior sensitivity of the MS-based assay in SARS-CoV-2 detection, showing that MALDI-TOF MS seems to be ideal for the detection as well as discrimination of mutations within the viral genome.

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