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1.
PLoS One ; 16(2): e0246302, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33591986

RESUMO

BACKGROUND: Two automatable in-house protocols for high-troughput RNA extraction from nasopharyngeal swabs for SARS-CoV-2 detection have been evaluated. METHODS: One hundred forty one SARS-CoV-2 positive samples were collected during a period of 10-days. In-house protocols were based on extraction with magnetic beads and designed to be used with either the Opentrons OT-2 (OT-2in-house) liquid handling robot or the MagMAXTM Express-96 system (MMin-house). Both protocols were tested in parallel with a commercial kit that uses the MagMAXTM system (MMkit). Nucleic acid extraction efficiencies were calculated from a SARS-CoV-2 DNA positive control. RESULTS: No significant differences were found between both in-house protocols and the commercial kit in their performance to detect positive samples. The MMkit was the most efficient although the MMin-house presented, in average, lower Cts than the other two. In-house protocols allowed to save between 350€ and 400€ for every 96 extracted samples compared to the commercial kit. CONCLUSION: The protocols described harness the use of easily available reagents and an open-source liquid handling system and are suitable for SARS-CoV-2 detection in high throughput facilities.


Assuntos
Automação Laboratorial/métodos , RNA Viral/normas , Automação Laboratorial/economia , Automação Laboratorial/normas , /normas , Custos e Análise de Custo , Humanos , RNA Viral/química , RNA Viral/genética , Kit de Reagentes para Diagnóstico/economia , Kit de Reagentes para Diagnóstico/normas , Sensibilidade e Especificidade
2.
Clin Lab ; 67(2)2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33616332

RESUMO

BACKGROUND AND METHODS: 2019 Corona Virus Disease (COVID-19) caused by SARS-CoV-2 is still pandemic now. RT-qPCR detection was the most common method for the diagnosis of SARS-CoV-2 infection, facilitated by amounts of nucleic acid testing kits. However, the accuracy of nucleic acid detection is affected by various factors such as specimen collection, specimen preparation, reagents deficiency, and personnel quality. RESULTS: In this study, we found that unmatched virus preservation solution will inhibit N gene and OFR-1ab gene (two independent genes of SARS-CoV-2) amplification in one-step detection reagent. CONCLUSIONS: Despite just being a particular phenomenon we found in our work to fight 2019-nCoV, we concluded that unmatched virus preservation solution may have an inhibitory effect on SARS-CoV-2 nucleic acid detection which may lead to incorrect clinical diagnosis.


Assuntos
/métodos , Genes Virais/efeitos dos fármacos , Soluções para Preservação de Órgãos/farmacologia , Manejo de Espécimes , /diagnóstico , Erros de Diagnóstico/prevenção & controle , Humanos , Kit de Reagentes para Diagnóstico/normas , /isolamento & purificação , Manejo de Espécimes/efeitos adversos , Manejo de Espécimes/métodos
3.
Bioanalysis ; 13(1): 13-28, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33319585

RESUMO

Aim: Coronavirus disease 2019 antibody testing often relies on venous blood collection, which is labor-intensive, inconvenient and expensive compared with finger-stick capillary dried blood spot (DBS) collection. The purpose of our work was to determine if two commercially available anti-severe acute respiratory syndrome coronavirus 2 enzyme-linked immunosorbent assays for IgG antibodies against spike S1 subunit and nucleocapsid proteins could be validated for use with DBS. Materials & methods: Kit supplied reagents were used to extract DBS, and in-house DBS calibrators were included on every run. Results: Positive/negative concordance between DBS and serum was 100/99.3% for the spike S1 subunit assay and 100/98% for the nucleocapsid assay. Conclusion: Validation of the DBS Coronavirus disease 2019 IgG antibody assays demonstrated that serum and DBS can produce equivalent results with minimal kit modifications.


Assuntos
/normas , Teste em Amostras de Sangue Seco/normas , Ensaio de Imunoadsorção Enzimática/normas , /imunologia , Anticorpos Antivirais/química , Antígenos Virais/sangue , Antígenos Virais/imunologia , /imunologia , /sangue , Feminino , Humanos , Imunoglobulina G/química , Masculino , Pessoa de Meia-Idade , Fosfoproteínas/sangue , Fosfoproteínas/imunologia , Kit de Reagentes para Diagnóstico/normas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus/sangue , Glicoproteína da Espícula de Coronavírus/imunologia
4.
J Clin Virol ; 134: 104712, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33338894

RESUMO

BACKGROUND: Currently, there are two rapid antigen detection (RAD) kits from the WHO Emergency Use List for detecting SARS-CoV-2. OBJECTIVE: The Panbio COVID-19 Ag Rapid Test Device was selected to evaluate the performance for detecting SARS-CoV-2. STUDY DESIGN: Analytical sensitivity for the detection of SARS-CoV-2 virus was determined by limit of detection (LOD) using RT-PCR as a reference method. Clinical sensitivity was evaluated by using respiratory specimens collected from confirmed COVID-19 patients. RESULTS: The LOD results showed that the RAD kit was 100 fold less sensitive than RT-PCR. Clinical sensitivity of the RAD kit was 68.6 % for detecting specimens from COVID-19 patients. CONCLUSIONS: The RAD kit evaluated in the present study shared similar performance with another kit from the WHO Emergency Use List, the Standard Q COVID-19 Ag. Understanding the clinical characteristics of RAD kits can guide us to decide different testing strategies in different settings.


Assuntos
Antígenos Virais/análise , Kit de Reagentes para Diagnóstico/normas , /imunologia , /patologia , /métodos , Reações Cruzadas , Hong Kong , Humanos , Limite de Detecção , Nasofaringe/virologia , Faringe/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Organização Mundial da Saúde
5.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(6): 537-540, 2020 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-33314864

RESUMO

From the perspective of technical review, this paper made statistics on the supplement contents of in vitro diagnostic reagent (kit) for clinical chemistry registered in Zhejiang province in the past five years, summarized and analyzed the common problems, and put forward corresponding suggestions based on the common problems encountered in the public welfare training of registered specialists in Zhejiang province. The aim is to provide technical reference for registrars to prepare registration documents reasonably and efficiently and for review staffs to strengthen their points of focus.


Assuntos
Química Clínica/normas , Kit de Reagentes para Diagnóstico/normas , China , Indicadores e Reagentes
6.
Ann Biol Clin (Paris) ; 78(6): 655-664, 2020 Dec 01.
Artigo em Francês | MEDLINE | ID: mdl-33361016

RESUMO

The lack of quality control for patient point-of-care (POC) INR devices is an issue that has led the French health authorities to make recommendations: a laboratory INR (lab INR) has to be performed at the same time as the POC INR every 6 months. However, the differences observed between the two INRs, POC and lab INRs, are not necessarily due to a failure of the POC INR device. We present here a review of the different causes of discrepancies between INR results, which are the basis of the proposals of the Groupe français d'études sur l'hémostase et la thrombose (GFHT) on the management of lab and POC INR discrepancies. Pre-analytical conditions may account for discrepancies (sampling, transport and storage conditions), as well as analytical factors (mainly the nature of the thromboplastin used) and the clinical context (inflammatory or autoimmune diseases, polycythaemia...). The interpretation of INR discrepancies is not always easy and these proposals aim at standardizing the procedure to be followed in order to make the most appropriate decision for the patient.


Assuntos
Técnicas de Laboratório Clínico/normas , Coeficiente Internacional Normatizado/métodos , Coeficiente Internacional Normatizado/normas , Kit de Reagentes para Diagnóstico/normas , 4-Hidroxicumarinas/uso terapêutico , Anticoagulantes/uso terapêutico , França , Humanos , Indenos/uso terapêutico , Laboratórios/normas , Ensaio de Proficiência Laboratorial/métodos , Ensaio de Proficiência Laboratorial/normas , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sociedades Científicas/normas , Trombose/sangue , Trombose/tratamento farmacológico , Vitamina K/antagonistas & inibidores , Vitamina K/uso terapêutico
7.
Int J Mol Sci ; 21(24)2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33321992

RESUMO

There is a lack of reliable biomarkers for disorders of the central nervous system (CNS), and diagnostics still heavily rely on symptoms that are both subjective and difficult to quantify. The cerebrospinal fluid (CSF) is a promising source of biomarkers due to its close connection to the CNS. Extracellular vesicles are actively secreted by cells, and proteomic analysis of CSF extracellular vesicles (EVs) and their molecular composition likely reflects changes in the CNS to a higher extent compared with total CSF, especially in the case of neuroinflammation, which could increase blood-brain barrier permeability and cause an influx of plasma proteins into the CSF. We used proximity extension assay for proteomic analysis due to its high sensitivity. We believe that this methodology could be useful for de novo biomarker discovery for several CNS diseases. We compared four commercially available kits for EV isolation: MagCapture and ExoIntact (based on magnetic beads), EVSecond L70 (size-exclusion chromatography), and exoEasy (membrane affinity). The isolated EVs were characterized by nanoparticle tracking analysis, ELISA (CD63, CD81 and albumin), and proximity extension assay (PEA) using two different panels, each consisting of 92 markers. The exoEasy samples did not pass the built-in quality controls and were excluded from downstream analysis. The number of detectable proteins in the ExoIntact samples was considerably higher (~150% for the cardiovascular III panel and ~320% for the cell regulation panel) compared with other groups. ExoIntact also showed the highest intersample correlation with an average Pearson's correlation coefficient of 0.991 compared with 0.985 and 0.927 for MagCapture and EVSecond, respectively. The median coefficient of variation was 5%, 8%, and 22% for ExoIntact, MagCapture, and EVSecond, respectively. Comparing total CSF and ExoIntact samples revealed 70 differentially expressed proteins in the cardiovascular III panel and 17 in the cell regulation panel. To our knowledge, this is the first time that CSF EVs were analyzed by PEA. In conclusion, analysis of CSF EVs by PEA is feasible, and different isolation kits give distinct results, with ExoIntact showing the highest number of identified proteins with the lowest variability.


Assuntos
Doenças do Sistema Nervoso Central/líquido cefalorraquidiano , Proteínas do Líquido Cefalorraquidiano/análise , Fracionamento Químico/métodos , Vesículas Extracelulares/metabolismo , Proteômica/métodos , Kit de Reagentes para Diagnóstico/normas , Biomarcadores/líquido cefalorraquidiano , Vesículas Extracelulares/química , Humanos
8.
Viruses ; 13(1)2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33374843

RESUMO

Measuring antibodies to evaluate dogs' immunity against canine parvovirus (CPV) is useful to avoid unnecessary re-vaccinations. The study aimed to evaluate the quality and practicability of four point-of-care (POC) tests for detection of anti-CPV antibodies. The sera of 198 client-owned and 43 specific pathogen-free (SPF) dogs were included; virus neutralization was the reference method. Specificity, sensitivity, positive and negative predictive value (PPV and NPV), and overall accuracy (OA) were calculated. Specificity was considered to be the most important indicator for POC test performance. Differences between specificity and sensitivity of POC tests in the sera of all dogs were determined by McNemar, agreement by Cohen's kappa. Prevalence of anti-CPV antibodies in all dogs was 80% (192/241); in the subgroup of client-owned dogs, it was 97% (192/198); and in the subgroup of SPF dogs, it was 0% (0/43). FASTest® and CanTiCheck® were easiest to perform. Specificity was highest in the CanTiCheck® (overall dogs, 98%; client-owned dogs, 83%; SPF dogs, 100%) and the TiterCHEK® (overall dogs, 96%; client-owned dogs, 67%; SPF dogs, 100%); no significant differences in specificity were observed between the ImmunoComb®, the TiterCHEK®, and the CanTiCheck®. Sensitivity was highest in the FASTest® (overall dogs, 95%; client-owned dogs, 95%) and the CanTiCheck® (overall dogs, 80%; client-owned dogs, 80%); sensitivity of the FASTest® was significantly higher compared to the one of the other three tests (McNemars p-value in each comparison: <0.001). CanTiCheck® would be the POC test of choice when considering specificity and practicability. However, differences in the number of false positive results between CanTiCheck®, TiterCHEK®, and ImmunoComb® were minimal.


Assuntos
Anticorpos Antivirais/imunologia , Doenças do Cão/diagnóstico , Doenças do Cão/imunologia , Infecções por Parvoviridae/veterinária , Parvovirus Canino/imunologia , Testes Imediatos , Kit de Reagentes para Diagnóstico , Animais , Anticorpos Antivirais/sangue , Vírus da Cinomose Canina/imunologia , Doenças do Cão/epidemiologia , Cães , Kit de Reagentes para Diagnóstico/normas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Testes Sorológicos/métodos , Testes Sorológicos/normas
9.
BMJ ; 371: m4262, 2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33177070

RESUMO

OBJECTIVE: To assess the accuracy of the AbC-19 Rapid Test lateral flow immunoassay for the detection of previous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. DESIGN: Test accuracy study. SETTING: Laboratory based evaluation. PARTICIPANTS: 2847 key workers (healthcare staff, fire and rescue officers, and police officers) in England in June 2020 (268 with a previous polymerase chain reaction (PCR) positive result (median 63 days previously), 2579 with unknown previous infection status); and 1995 pre-pandemic blood donors. MAIN OUTCOME MEASURES: AbC-19 sensitivity and specificity, estimated using known negative (pre-pandemic) and known positive (PCR confirmed) samples as reference standards and secondly using the Roche Elecsys anti-nucleoprotein assay, a highly sensitive laboratory immunoassay, as a reference standard in samples from key workers. RESULTS: Test result bands were often weak, with positive/negative discordance by three trained laboratory staff for 3.9% of devices. Using consensus readings, for known positive and negative samples sensitivity was 92.5% (95% confidence interval 88.8% to 95.1%) and specificity was 97.9% (97.2% to 98.4%). Using an immunoassay reference standard, sensitivity was 94.2% (90.7% to 96.5%) among PCR confirmed cases but 84.7% (80.6% to 88.1%) among other people with antibodies. This is consistent with AbC-19 being more sensitive when antibody concentrations are higher, as people with PCR confirmation tended to have more severe disease whereas only 62% (218/354) of seropositive participants had had symptoms. If 1 million key workers were tested with AbC-19 and 10% had actually been previously infected, 84 700 true positive and 18 900 false positive results would be projected. The probability that a positive result was correct would be 81.7% (76.8% to 85.8%). CONCLUSIONS: AbC-19 sensitivity was lower among unselected populations than among PCR confirmed cases of SARS-CoV-2, highlighting the scope for overestimation of assay performance in studies involving only PCR confirmed cases, owing to "spectrum bias." Assuming that 10% of the tested population have had SARS-CoV-2 infection, around one in five key workers testing positive with AbC-19 would be false positives. STUDY REGISTRATION: ISRCTN 56609224.


Assuntos
Técnicas de Laboratório Clínico/normas , Infecções por Coronavirus/diagnóstico , Imunoensaio/normas , Pneumonia Viral/diagnóstico , Betacoronavirus , Feminino , Bombeiros , Pessoal de Saúde , Humanos , Masculino , Pandemias , Polícia , Valor Preditivo dos Testes , Kit de Reagentes para Diagnóstico/normas , Sensibilidade e Especificidade , Reino Unido
10.
PLoS Biol ; 18(10): e3000896, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33006983

RESUMO

The ongoing COVID-19 pandemic has created an unprecedented need for rapid diagnostic testing. The World Health Organization (WHO) recommends a standard assay that includes an RNA extraction step from a nasopharyngeal (NP) swab followed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) to detect the purified SARS-CoV-2 RNA. The current global shortage of RNA extraction kits has caused a severe bottleneck to COVID-19 testing. The goal of this study was to determine whether SARS-CoV-2 RNA could be detected from NP samples via a direct RT-qPCR assay that omits the RNA extraction step altogether. The direct RT-qPCR approach correctly identified 92% of a reference set of blinded NP samples (n = 155) demonstrated to be positive for SARS-CoV-2 RNA by traditional clinical diagnostic RT-qPCR that included an RNA extraction. Importantly, the direct method had sufficient sensitivity to reliably detect those patients with viral loads that correlate with the presence of infectious virus. Thus, this strategy has the potential to ease supply choke points to substantially expand COVID-19 testing and screening capacity and should be applicable throughout the world.


Assuntos
Betacoronavirus/genética , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , RNA Viral/genética , Kit de Reagentes para Diagnóstico/normas , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Betacoronavirus/patogenicidade , Técnicas de Laboratório Clínico/normas , Infecções por Coronavirus/virologia , Primers do DNA/normas , Humanos , Nasofaringe/virologia , Pandemias , Pneumonia Viral/virologia , Sensibilidade e Especificidade , Estados Unidos , Carga Viral
11.
PLoS Biol ; 18(10): e3000867, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33027248

RESUMO

The current quantitative reverse transcription PCR (RT-qPCR) assay recommended for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing in the United States requires analysis of 3 genomic targets per sample: 2 viral and 1 host. To simplify testing and reduce the volume of required reagents, we devised a multiplex RT-qPCR assay to detect SARS-CoV-2 in a single reaction. We used existing N1, N2, and RP primer and probe sets by the Centers for Disease Control and Prevention, but substituted fluorophores to allow multiplexing of the assay. The cycle threshold (Ct) values of our multiplex RT-qPCR were comparable to those obtained by the single assay adapted for research purposes. Low copy numbers (≥500 copies/reaction) of SARS-CoV-2 RNA were consistently detected by the multiplex RT-qPCR. Our novel multiplex RT-qPCR improves upon current single diagnostics by saving reagents, costs, time, and labor.


Assuntos
Betacoronavirus/genética , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Reação em Cadeia da Polimerase Multiplex/normas , Pneumonia Viral/diagnóstico , RNA Viral/genética , Kit de Reagentes para Diagnóstico/normas , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Betacoronavirus/patogenicidade , Estudos de Casos e Controles , Técnicas de Laboratório Clínico/normas , Infecções por Coronavirus/virologia , Primers do DNA/normas , Células HEK293 , Humanos , Limite de Detecção , Nasofaringe/virologia , Pandemias , Pneumonia Viral/virologia , Estados Unidos
12.
Biomed Eng Online ; 19(1): 75, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33008462

RESUMO

BACKGROUND: The world is facing an unprecedented outbreak affecting all aspects of human lives which is caused by the COVID-19 pandemic. Due to the virus novelty, healthcare systems are challenged by a high rate of patients and the shortage of medical products. To address an increased need for essential medical products, national authorities, worldwide, made various legislative concessions. This has led to essential medical products being produced by automotive, textile and other companies from various industries and approved under the emergency use authorizations or legal concessions of national regulatory bodies. This paper presents a narrative commentary of the available documentation on emergency use authorizations and legal concessions for medical products during COVID-19 pandemic. METHODOLOGY: The basis for narrative commentary includes scientific articles published in Web of Science, Scopus, PubMed and Embase databases, official publications of international organizations: Food and Drug Agency (FDA), World Health Organisation (WHO), World Bank and United Nations (UN), and national regulatory agency reports in native languages (English, German, Bosnian, and Croatian) published from November 1, 2019 to May 1, 2020. This paper focuses on three types of essential medical products: mechanical ventilators, personal protective equipment (PPE) and diagnostic tests. Evidence-informed commentary of available data and potential identified risks of emergency use authorizations and legal concessions is presented. DISCUSSION: It is recognized that now more than ever, raising global awareness and knowledge about the importance of respecting the essential requirements is needed to guarantee the appropriate quality, performance and safety of medical products, especially during outbreak situation, such as the COVID-19 pandemic. Emergency use authorizations for production, import and approval of medical products should be strictly specified and clearly targeted from case to case and should not be general or universal for all medical products, because all of them are associated with different risk level. CONCLUSION: Presented considerations and experiences should be taken as a guide for all possible future outbreak situations to prevent improvised reactions of national regulatory bodies.


Assuntos
Betacoronavirus , Comércio/legislação & jurisprudência , Infecções por Coronavirus , Licenciamento/legislação & jurisprudência , Indústria Manufatureira/legislação & jurisprudência , Pandemias , Equipamento de Proteção Individual/provisão & distribução , Pneumonia Viral , Kit de Reagentes para Diagnóstico/provisão & distribução , Ventiladores Mecânicos/provisão & distribução , Técnicas de Laboratório Clínico/normas , Infecções por Coronavirus/diagnóstico , Falha de Equipamento , União Europeia , Saúde Global , Humanos , Equipamento de Proteção Individual/normas , Kit de Reagentes para Diagnóstico/normas , Medição de Risco , Estados Unidos , United States Food and Drug Administration , Ventiladores Mecânicos/normas
14.
PLoS One ; 15(10): e0240779, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33057446

RESUMO

The practicability of a prototype capillary whole-blood IgG-IgM COVID-19 self-test (Exacto® COVID-19 self-test, Biosynex Swiss SA, Freiburg, Switzerland) as a serological screening tool for SARS-CoV-2 infection adapted to the general public was evaluated in a cross-sectional, general adult population study performed between April and May 2020 in Strasbourg, France, consisting of face-to-face, paper-based, semi-structured, and self-administrated questionnaires. Practicability was defined as the correct use of the self-test and the correct interpretation of the result. The correct use of self-test was conditioned by the presence of the control band after 15-min of migration. The correct interpretation of the tests was defined by the percent agreement between the tests results read and interpret by the participants compared to the expected results coded by the numbers and verified by trained observers. A total of 167 participants (52.7% female; median age, 35.8 years; 82% with post-graduate level) were enrolled, including 83 and 84 for usability and test results interpretation substudies, respectively. All participants (100%; 95% CI: 95.6-100) correctly used the self-test. However, 12 (14.5%; 95% CI: 8.5-23.6) asked for verbal help. The percent agreement between the tests results read and interpret by the participants compared to the expected results was 98.5% (95% CI: 96.5-99.4). However, misinterpretation occurred in only 2.3% of positive and 1.2% of invalid test results. Finally, all (100%) participants found that performing the COVID-19 self-test was easy; and 98.8% found the interpretation of the self-test results easy. Taken together, these pilot observations demonstrated for the first-time, high practicability and satisfaction of COVID-19 self-testing for serological IgG and IgM immune status, indicating its potential for use by the general public to complete the arsenal of available SARS-CoV-2 serological assays in the urgent context of the COVID-19 epidemic.


Assuntos
Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Kit de Reagentes para Diagnóstico/normas , Adulto , Técnicas de Laboratório Clínico/normas , Infecções por Coronavirus/sangue , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Programas de Rastreamento/métodos , Programas de Rastreamento/normas , Pandemias , Pneumonia Viral/sangue , Testes Imediatos , Autoadministração , Sensibilidade e Especificidade
16.
J Virol Methods ; 285: 113970, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32920028

RESUMO

The global COVID-19 pandemic has led to the rapid development of tests for detection of SARS-CoV-2. Studies are required to assess the relative performance of different assays. Here, we compared the performance of two commercial assays, the cobas® SARS-CoV-2 (Roche Diagnostics) and Xpert® Xpress SARS-CoV-2 (Cepheid®) tests, and a laboratory developed RT-PCR test adapted for use on the Hologic® Panther Fusion® (Hologic®) instrument as well as Bio-Rad and QIAGEN real-time PCR detection systems. Performance characteristics for each test were determined by testing clinical specimens and reference material. All assays detect the pan-Sarbecovirus E (envelope structural protein) gene plus a SARS-CoV-2-specific target. The limit of detection for the E gene target varied from ∼2 copies/reaction to >30 copies/reaction. Due to assay-specific differences in sample processing and nucleic acid extraction, the overall analytical sensitivity ranged from 24 copies/mL specimen to 574 copies/mL specimen. Despite these differences, there was 100 % agreement between the commercial and laboratory developed tests. No false-negative or false-positive SARS-CoV-2 results were observed and there was no cross-reactivity with common respiratory viruses, including endemic coronaviruses.


Assuntos
Betacoronavirus , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Técnicas de Diagnóstico Molecular , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia , Kit de Reagentes para Diagnóstico , Betacoronavirus/genética , Betacoronavirus/imunologia , Técnicas de Laboratório Clínico/métodos , Técnicas de Laboratório Clínico/normas , Humanos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/normas , Pandemias , Kit de Reagentes para Diagnóstico/normas , Sensibilidade e Especificidade
17.
Eur J Clin Microbiol Infect Dis ; 39(12): 2289-2297, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32808111

RESUMO

Lateral flow immunoassays (LFIA) for rapid detection of specific antibodies (IgM and IgG) against SARS-CoV-2 in different human specimens have been developed in response to the pandemic. The aim of this study is to evaluate three immunocromathographic assays (Sienna®, Wondfo® and Prometheus®) for detection of antibodies against SARS-CoV-2 in serum samples, considering RT-qPCR as a reference. A total of 145 serum samples from 145 patients with clinical suspicion of COVID-19 were collected: all of the samples were tested with Sienna®, 117 with Wondfo® and 89 with Prometheus®. The overall results of sensitivity, specificity, positive predictive value and negative predictive value obtained were as follows: 64.4%, 75%, 85.5% and 47.8% with Sienna®; 45.2%, 81.8%, 80.5% and 47.4% with Wondfo® and 75.5%, 12.5%, 51.4% and 29.4% with Prometheus®. The accuracy of the test for Sienna®, Wondfo® and Prometheus® was 67.6%, 59% and 47.2%, with a prevalence of COVID-19 of 69.7%, 62.4% and 55.1% respectively. Sensitivity of the three tests (Sienna®, Wondfo® and Prometheus® respectively) along the three different stages was 36.6%, 18.8% and 68.6% in the early stage (first week); 81.3%, 74.1% and 90.9% in the intermediate stage (second week) and 100%, 83.3% and 100% in the late stage (third week). The results demonstrate that even though Prometheus® presented a high sensitivity, the specificity was notably lower than the other two tests. Sienna® showed the greatest contrast between sensitivity and specificity, achieving the best accuracy, followed by Wondfo®. The sensitivity of the three ICT assays was higher in late stages of the disease.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Cromatografia de Afinidade/métodos , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Pandemias , Pneumonia Viral/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus/patogenicidade , Estudos de Casos e Controles , Infecções por Coronavirus/sangue , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Reações Falso-Positivas , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/sangue , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Kit de Reagentes para Diagnóstico/normas , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Espanha/epidemiologia
18.
J Clin Virol ; 130: 104569, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32769023

RESUMO

BACKGROUND: The emergence of the global SARS-CoV-2 pandemic required the rapid and large-scale deployment of PCR and serological tests in different formats. OBJECTIVES: Real-life evaluation of these tests is needed. Using 168 samples from patients hospitalized for COVID-19, non-hospitalized patients but infected with SARS-CoV-2, patients participating in screening campaigns, and samples from patients with a history of other seasonal coronavirus infections, we evaluated the clinical performance of 5 serological assays widely used worldwide (WANTAI®, BIORAD®, EUROIMMUN®, ABBOTT® and LIAISON®). RESULTS: For hospitalized patients, all these assays showed a sensitivity of 100 % from day 9 after the symptoms onset. On the other hand, sensitivity was much lower for patients who did not require hospitalization for COVID-19 confirmed by PCR (from 91.6 % for WANTAI® to 69 % for LIAISON®). These differences do not seem to be due to the antigens chosen by the manufacturers but more to the test formats (IgG detection versus total antibodies). In addition, more than 50 days after a positive PCR for CoV-2-SARS the proportion of positive patients seem to decrease. We did not observe any significant cross-reactions for these techniques with the four other seasonal coronaviruses. CONCLUSION: In conclusion, the evaluation and knowledge of the serological tests used is important and should require an optimized strategy adaptation of the analysis laboratories to best meet patient's expectations in the face of this health crisis.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Testes Sorológicos/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus , Técnicas de Laboratório Clínico , Infecções por Coronavirus/imunologia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/imunologia , Kit de Reagentes para Diagnóstico/normas , Sensibilidade e Especificidade , Adulto Jovem
19.
J Clin Microbiol ; 58(11)2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-32843531

RESUMO

Frequent, low-cost, universal testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with quarantine of those with a positive result has been suggested as a strategy to address the coronavirus disease 2019 (COVID-19) pandemic in the United States. Specifically, home or community use of tests that use paper strip detection devices, which may have reduced sensitivity for SARS-CoV-2, has been advocated. There are several potential challenges or problems with this strategy, including the limited availability of such tests, consequences of incorrect test results, difficulties with adherence to testing, and the questionable accuracy of such tests for detection of infectious people. Because of these, we think it is premature to strongly advocate for such a testing strategy, as the adverse consequences may outweigh any benefits. High-quality outcome data demonstrating the efficacy of this testing strategy are needed before widespread implementation.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Técnicas de Laboratório Clínico , Infecções por Coronavirus/prevenção & controle , Humanos , Programas de Rastreamento , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Kit de Reagentes para Diagnóstico/normas , Kit de Reagentes para Diagnóstico/provisão & distribução , Sensibilidade e Especificidade , Estados Unidos/epidemiologia
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