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1.
PLoS One ; 15(9): e0237694, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32941461

RESUMO

BACKGROUND: The SARS-CoV-2 (Severe Acute Respiratory Syndrome CoronaVirus 2) is responsible for the infectious respiratory disease called COVID-19 (COronaVIrus Disease 2019). In response to the growing COVID-19 pandemic, point-of-care (POC) tests have been developed to detect specific antibodies, IgG and IgM, to SARS-CoV-2 virus in human whole blood. We conducted a prospective observational study to evaluate the performance of two POC tests, COVID-PRESTO® and COVID-DUO®, compared to the gold standard, RT-PCR (real-time reverse transcriptase polymerase chain reaction). METHODS: RT-PCR testing of SARS-Cov-2 was performed from nasopharyngeal swab specimens collected in adult patients visiting the infectious disease department at the hospital (Orléans, France). Capillary whole blood (CWB) samples from the fingertip taken at different time points after onset of the disease were tested with POC tests. The specificity and sensitivity of the rapid test kits compared to test of reference (RT-PCR) were calculated. RESULTS: Among 381 patients with symptoms of COVID-19 who went to the hospital for a diagnostic, 143 patients were RT-PCR negative. Results of test with POC tests were all negative for these patients, indicating a specificity of 100% for both POC tests. In the RT-PCR positive subgroup (n = 238), 133 patients were tested with COVID-PRESTO® and 129 patients were tested with COVID-DUO® (24 patients tested with both). The further the onset of symptoms was from the date of collection, the greater the sensitivity. The sensitivity of COVID-PRESTO® test ranged from 10.00% for patients having experienced their 1st symptoms from 0 to 5 days ago to 100% in patients where symptoms had occurred more than 15 days before the date of tests. For COVID-DUO® test, the sensitivity ranged from 35.71% [0-5 days] to 100% (> 15 days). CONCLUSION: COVID-PRESTO® and DUO® POC tests turned out to be very specific (none false positive) and to be sensitive enough after 15 days from onset of symptom. These easy to use IgG/IgM combined test kits are the first ones allowing a screening with CWB sample, by typing from a finger prick. These rapid tests are particularly interesting for screening in low resource settings.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Imunoensaio/métodos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Pneumonia Viral/diagnóstico , Kit de Reagentes para Diagnóstico , Adulto , Idoso , Especificidade de Anticorpos , Betacoronavirus/genética , Betacoronavirus/isolamento & purificação , Capilares , Infecções por Coronavirus/sangue , Dedos/irrigação sanguínea , Humanos , Pessoa de Meia-Idade , Nasofaringe/virologia , Pandemias , Pneumonia Viral/sangue , Testes Imediatos , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Adulto Jovem
2.
J Nanobiotechnology ; 18(1): 130, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32912236

RESUMO

Fast point-of-care (POC) diagnostics represent an unmet medical need and include applications such as lateral flow assays (LFAs) for the diagnosis of sepsis and consequences of cytokine storms and for the treatment of COVID-19 and other systemic, inflammatory events not caused by infection. Because of the complex pathophysiology of sepsis, multiple biomarkers must be analyzed to compensate for the low sensitivity and specificity of single biomarker targets. Conventional LFAs, such as gold nanoparticle dyed assays, are limited to approximately five targets-the maximum number of test lines on an assay. To increase the information obtainable from each test line, we combined green and red emitting quantum dots (QDs) as labels for C-reactive protein (CRP) and interleukin-6 (IL-6) antibodies in an optical duplex immunoassay. CdSe-QDs with sharp and tunable emission bands were used to simultaneously quantify CRP and IL-6 in a single test line, by using a single UV-light source and two suitable emission filters for readout through a widely available BioImager device. For image and data processing, a customized software tool, the MultiFlow-Shiny app was used to accelerate and simplify the readout process. The app software provides advanced tools for image processing, including assisted extraction of line intensities, advanced background correction and an easy workflow for creation and handling of experimental data in quantitative LFAs. The results generated with our MultiFlow-Shiny app were superior to those generated with the popular software ImageJ and resulted in lower detection limits. Our assay is applicable for detecting clinically relevant ranges of both target proteins and therefore may serve as a powerful tool for POC diagnosis of inflammation and infectious events.


Assuntos
Biomarcadores/análise , Proteína C-Reativa/análise , Imunoensaio/métodos , Interleucina-6/análise , Pontos Quânticos/química , Sepse/diagnóstico , Anticorpos/imunologia , Betacoronavirus/isolamento & purificação , Proteína C-Reativa/imunologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Humanos , Interleucina-6/imunologia , Limite de Detecção , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia , Sistemas Automatizados de Assistência Junto ao Leito , Sepse/metabolismo , Software , Raios Ultravioleta
3.
J Clin Virol ; 131: 104609, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32866811

RESUMO

INTRODUCTION: IgG immunoassays have been developed and used widely for clinical samples and serosurveys for SARS-CoV2, with most detecting antibodies against the spike/receptor-binding-domain or nucleocapsid. Limited information is available on comparative evaluation of IgG immunoassays against a clinical reference standard, i.e., RT-PCR positivity with >20 days of illness. This study addresses the need for comparing clinical performance of IgG immunoassays with respect to this alternate reference standard. METHODS: We compared the performance of three immunoassays, an in-house RBD assay, and two commercial assays, the Diasorin LIAISON SARS-CoV-2 S1/S1 IgG CLIA which detects antibodies against S1/S2 domains of the Spike protein and the Zydus Kavach assay based on inactivated virus using a well-characterized panel of sera. 379 sera and plasma samples from RTPCR positive individuals >20 days of illness in symptomatic or RT-PCR positivity in asymptomatic individuals and 184 samples collected prior to 2019 were used for assay evaluation. RESULTS: The sensitivity of the assays were 84.7 (95 %CI 80.6-88.1), 82.6 (95 %CI 78.3-86.2) and 75.7 (95 %CI 71.0-79.9) respectively for RBD, LIAISON and Kavach. Kavach and the in-house RBD ELISA showed a specificity of 99.5 % and 100 %, respectively. The RBD and LIAISON (S1/S2) assays showed high agreement (94.7 %; 95 %CI: 92.0, 96.6) and were able to correctly identify more positive sera/plasma than Kavach. CONCLUSION: Independent comparisons support the evaluation of performance characteristics of immunoassays. All three assays are suitable for serosurveillance studies, but in low prevalence sites, estimation of exposure may require adjustment based on our findings.


Assuntos
Anticorpos Antivirais/sangue , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/imunologia , Imunoensaio/métodos , Imunoglobulina G/sangue , Pneumonia Viral/imunologia , Automação Laboratorial , Betacoronavirus , Infecções por Coronavirus/diagnóstico , Humanos , Índia , Estudos Longitudinais , Medições Luminescentes , Pandemias , Estudos Prospectivos , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade
4.
BMC Infect Dis ; 20(1): 650, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887568

RESUMO

BACKGROUND: Cryptococcus is a conditional pathogenic fungus causing cryptococcosis, which is one of the most serious fungal diseases faced by humans. Lateral flow immunochromatographic assay (LFA) is successfully applied to the rapid detection of cryptococcal antigens. METHODS: Studies were retrieved systematically from the Embase, PubMed, Web of Science, and Cochrane Library before July 2019. The quality of the studies was assessed by Review Manager 5.0 based on the Quality Assessment of Diagnostic Accuracy Study guidelines. The extracted data from the included studies were analyzed by Meta-DiSc 1.4. Stata 12.0 software was used to detect the publication bias. RESULTS: A total of 15 articles with 31 fourfold tables were adopted by inclusion and exclusion criteria. The merged sensitivity and specificity in serum were 0.98 and 0.98, respectively, and those in the cerebrospinal fluid were 0.99 and 0.99, respectively. CONCLUSIONS: Compared to the urine and other samples, LFA in serum and cerebrospinal fluid is favorable evidence for the diagnosis of cryptococcosis with high specificity and sensitivity.


Assuntos
Criptococose/diagnóstico , Imunoensaio/métodos , Antígenos de Fungos/sangue , Antígenos de Fungos/líquido cefalorraquidiano , Antígenos de Fungos/urina , Líquido Cefalorraquidiano/microbiologia , Testes Diagnósticos de Rotina/métodos , Humanos , Sensibilidade e Especificidade
5.
Diagn Microbiol Infect Dis ; 98(3): 115161, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947206

RESUMO

In a Clinical Laboratory Improvement Amendments laboratory setting, we evaluated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG detection with 4 lateral flow immunoassays [LFIAs; 2 iterations from BTNX Inc. (n = 457) and 1 each from ACON Laboratories (n = 200) and SD BIOSENSOR (n = 155)]. In a cohort of primarily hospitalized, reverse-transcription polymerase chain reaction-confirmed coronavirus disease 2019 cases, sensitivity at ≥14 days from symptom onset was: BTNX kit 1, 95%; BTNX kit 2, 91%; ACON, 95%; and SD, 92%. All assays showed good concordance with the Abbott SARS-CoV-2 IgG assay at ≥14 days from symptom onset: BTNX kit 1, 99%; BTNX kit 2, 94%; ACON, 99%; and SD, 100%. Specificity, measured using specimens collected prior to SARS-CoV-2 circulation in the United States and "cross-reactivity challenge" specimens, was 98% for BTNX kit 1 and ACON and 100% for BTNX kit 2 and SD. These results suggest that LFIAs may provide adequate results for rapid detection of SARS-CoV-2.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Infecções por Coronavirus/diagnóstico , Imunoensaio/métodos , Imunoglobulina G/sangue , Pneumonia Viral/diagnóstico , Humanos , Pandemias , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e Especificidade
6.
Emerg Microbes Infect ; 9(1): 2200-2211, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32962560

RESUMO

Serology detection is recognized for its sensitivity in convalescent patients with COVID-19, in comparison with nucleic acid amplification tests (NAATs). This article aimed to evaluate the diagnostic accuracy of serologic methods for COVID-19 based on assay design and post-symptom-onset intervals. Two authors independently searched PubMed, Cochrane library, Ovid, EBSCO for case-control, longitudinal and cohort studies that determined the diagnostic accuracy of serology tests in comparison with NAATs in COVID-19 cases and used QUADAS-2 for quality assessment. Pooled accuracy was analysed using INLA method. A total of 27 studies were included in this meta-analysis, with 4 cohort, 16 case-control and 7 longitudinal studies and 4565 participants. Serology tests had the lowest sensitivity at 0-7 days after symptom onset and the highest at >14 days. TAB had a better sensitivity than IgG or IgM only. Using combined nucleocapsid (N) and spike(S) protein had a better sensitivity compared to N or S protein only. Lateral flow immunoassay (LFIA) had a lower sensitivity than enzyme-linked immunoassay (ELISA) and chemiluminescent immunoassay (CLIA). Serology tests will play an important role in the clinical diagnosis for later stage COVID-19 patients. ELISA tests, detecting TAB or targeting combined N and S proteins had a higher diagnostic sensitivity compared to other methods.


Assuntos
Betacoronavirus , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia , Testes Sorológicos/métodos , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Betacoronavirus/imunologia , Técnicas de Laboratório Clínico/normas , Infecções por Coronavirus/imunologia , Humanos , Imunoensaio/métodos , Imunoensaio/normas , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Pandemias , Pneumonia Viral/imunologia , Viés de Publicação , Sensibilidade e Especificidade , Testes Sorológicos/normas , Avaliação de Sintomas
7.
Biosens Bioelectron ; 169: 112604, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32980805

RESUMO

Virus severely endangers human life and health, and the detection of viruses is essential for the prevention and treatment of associated diseases. Metal-organic framework (MOF), a novel hybrid porous material which is bridged by the metal clusters and organic linkers, has become a promising biosensor platform for virus detection due to its outstanding properties including high surface area, adjustable pore size, easy modification, etc. However, the MOF-based sensing platforms for virus detection are rarely summarized. This review systematically divided the detection platforms into nucleic acid and immunological (antigen and antibody) detection, and the underlying sensing mechanisms were interpreted. The nucleic acid sensing was discussed based on the properties of MOF (such as metal ion, functional group, geometry structure, size, porosity, stability, etc.), revealing the relationship between the sensing performance and properties of MOF. Moreover, antibodies sensing based on the fluorescence detection and antigens sensing based on molecular imprinting or electrochemical immunoassay were highlighted. Furthermore, the remaining challenges and future development of MOF for virus detection were further discussed and proposed. This review will provide valuable references for the construction of sophisticated sensing platform for the detection of viruses, especially the 2019 coronavirus.


Assuntos
Técnicas Biossensoriais/métodos , Estruturas Metalorgânicas/química , Viroses/virologia , Vírus/isolamento & purificação , Animais , Anticorpos Antivirais/análise , Antígenos Virais/análise , Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Humanos , Imunoensaio/instrumentação , Imunoensaio/métodos , Modelos Moleculares , Impressão Molecular/instrumentação , Impressão Molecular/métodos , Ácidos Nucleicos/análise , Espectrometria de Fluorescência/instrumentação , Espectrometria de Fluorescência/métodos , Viroses/diagnóstico
8.
Emerg Microbes Infect ; 9(1): 2157-2168, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32940547

RESUMO

This multicenter, retrospective study included 346 serum samples from 74 patients with coronavirus disease 2019 (COVID-19) and 194 serum samples from non-COVID-19 patients to evaluate the performance of five anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody tests, i.e. two chemiluminescence immunoassays (CLIAs): Roche Elecsys® Anti-SARS-CoV-2 Test (Roche Test) and Abbott SARS-CoV-2 IgG (Abbott Test), and three lateral flow immunoassays (LFIAs): Wondfo SARS-CoV-2 Antibody Test (Wondfo Test), ASK COVID-19 IgG/IgM Rapid Test (ASK Test), and Dynamiker 2019-nCoV IgG/IgM Rapid Test (Dynamiker Test). We found high diagnostic sensitivities (%, 95% confidence interval [CI]) for the Roche Test (97.4%, 93.4-99.0%), Abbott Test (94.0%, 89.1-96.8%), Wondfo Test (91.4%, 85.8-94.9%), ASK Test (97.4%, 93.4-99.0%), and Dynamiker Test (90.1%, 84.3-94.0%) after >21 days of symptom onset. Meanwhile, the diagnostic specificity was 99.0% (95% CI, 96.3-99.7%) for the Roche Test, 97.9% (95% CI, 94.8-99.2%) for the Abbott Test, and 100.0% (95% CI, 98.1-100.0%) for the three LFIAs. Cross-reactivity was observed in sera containing anti-cytomegalovirus (CMV) IgG/IgM antibodies and autoantibodies. No difference was observed in the time to seroconversion detection of the five serological tests. Specimens from patients with COVID-19 pneumonia demonstrated a shorter seroconversion time and higher chemiluminescent signal than those without pneumonia. Our data suggested that understanding the dynamic antibody response after COVID-19 infection and performance characteristics of different serological test are crucial for the appropriate interpretation of serological test result for the diagnosis and risk assessment of patient with COVID-19 infection.


Assuntos
Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/imunologia , Imunoensaio/métodos , Medições Luminescentes/métodos , Pneumonia Viral/diagnóstico , Pneumonia Viral/imunologia , Adulto , Idoso , Anticorpos Antivirais/sangue , Betacoronavirus/genética , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Reações Cruzadas/imunologia , Feminino , Humanos , Imunoensaio/normas , Medições Luminescentes/normas , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Reprodutibilidade dos Testes , Soroconversão , Testes Sorológicos , Índice de Gravidade de Doença , Taiwan/epidemiologia
10.
ACS Sens ; 5(9): 2663-2678, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32786383

RESUMO

The global sanitary crisis caused by the emergence of the respiratory virus SARS-CoV-2 and the COVID-19 outbreak has revealed the urgent need for rapid, accurate, and affordable diagnostic tests to broadly and massively monitor the population in order to properly manage and control the spread of the pandemic. Current diagnostic techniques essentially rely on polymerase chain reaction (PCR) tests, which provide the required sensitivity and specificity. However, its relatively long time-to-result, including sample transport to a specialized laboratory, delays massive detection. Rapid lateral flow tests (both antigen and serological tests) are a remarkable alternative for rapid point-of-care diagnostics, but they exhibit critical limitations as they do not always achieve the required sensitivity for reliable diagnostics and surveillance. Next-generation diagnostic tools capable of overcoming all the above limitations are in demand, and optical biosensors are an excellent option to surpass such critical issues. Label-free nanophotonic biosensors offer high sensitivity and operational robustness with an enormous potential for integration in compact autonomous devices to be delivered out-of-the-lab at the point-of-care (POC). Taking the current COVID-19 pandemic as a critical case scenario, we provide an overview of the diagnostic techniques for respiratory viruses and analyze how nanophotonic biosensors can contribute to improving such diagnostics. We review the ongoing published work using this biosensor technology for intact virus detection, nucleic acid detection or serological tests, and the key factors for bringing nanophotonic POC biosensors to accurate and effective COVID-19 diagnosis on the short term.


Assuntos
Betacoronavirus , Infecções por Coronavirus/diagnóstico , Nanoestruturas/química , Pneumonia Viral/diagnóstico , Ressonância de Plasmônio de Superfície/métodos , Antígenos Virais/análise , Betacoronavirus/química , Betacoronavirus/isolamento & purificação , Técnicas de Laboratório Clínico , Genoma Viral , Humanos , Imunoensaio/métodos , Nanoestruturas/efeitos da radiação , Pandemias , Testes Sorológicos/métodos
11.
Int J Nanomedicine ; 15: 4933-4941, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764926

RESUMO

Purpose: The aim of this study was to develop an avidin-modified macromolecular lipid magnetic sphere and its application in differential diagnosis of liver disease and liver cancer. Materials and Methods: Lectin-modified macromolecular lipid magnetic spheres were prepared by thin-film hydration method using lentil lectin derivatives (LCA-HQ) and cholesterol as raw materials. Alpha-fetoprotein variants (AFP-L3) in serum from healthy people, liver disease and liver cancer patients were isolated using the prepared lectin-modified macromolecular lipid magnetic spheres, and alpha-fetoprotein (AFP) and AFP-L3 were detected by fully automatic time-resolved fluorescence immunoassay. Results: The lectin polymer lipid magnetic sphere prepared in this study was superparamagnetic and encapsulated by a lectin derivative. There was no significant difference in the recovery rate of AFP-L3 between avidin magnetic ball-automatic time-resolved fluorescence immunoassay and manual micro-affinity column method (p>0.05). We found that AFP-L3 can be used as a differential indicator between liver cancer and liver disease. The positive rate of AFP and AFP-L3 in liver cancer patients was higher than that in healthy people and liver disease patients (p<0.001). The AUC (95% CI) of AFP and AFP-L3 were 0.743 ± 0.031 and 0.850 ± 0.024, respectively. AFP-L3 AUC value is greater than AFP; therefore, AFP-L3 distinguishes liver cancer more accurately, and the difference is statistically different, p<0.05. Conclusion: We proposed a novel method for integration of the lectin polymer lipid magnetic spheres and time-resolved fluorescence immunoassay that enables simple, accurate and rapid determination of AFP-L3 in clinical samples. To be noted, fully automatic time-resolved fluorescence immunoassay compared with the commonly used techniques in clinical practice, the measurement procedure is simple and is expected to be used for the detection and accurate diagnosis of liver cancer.


Assuntos
Fluorescência , Lipossomos/química , Neoplasias Hepáticas/diagnóstico , Mutação , Polímeros/química , alfa-Fetoproteínas/genética , alfa-Fetoproteínas/metabolismo , Adulto , Área Sob a Curva , Automação , Biomarcadores Tumorais/sangue , Feminino , Humanos , Imunoensaio/métodos , Neoplasias Hepáticas/sangue , Imãs/química , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
12.
Sensors (Basel) ; 20(15)2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32752043

RESUMO

Coronaviruses have received global concern since 2003, when an outbreak caused by SARS-CoV emerged in China. Later on, in 2012, the Middle-East respiratory syndrome spread in Saudi Arabia, caused by MERS-CoV. Currently, the global crisis is caused by the pandemic SARS-CoV-2, which belongs to the same lineage of SARS-CoV. In response to the urgent need of diagnostic tools, several lab-based and biosensing techniques have been proposed so far. Five main areas have been individuated and discussed in terms of their strengths and weaknesses. The cell-culture detection and the microneutralization tests are still considered highly reliable methods. The genetic screening, featuring the well-established Real-time polymerase chain reaction (RT-PCR), represents the gold standard for virus detection in nasopharyngeal swabs. On the other side, immunoassays were developed, either by screening/antigen recognition of IgM/IgG or by detecting the whole virus, in blood and sera. Next, proteomic mass-spectrometry (MS)-based methodologies have also been proposed for the analysis of swab samples. Finally, virus-biosensing devices were efficiently designed. Both electrochemical immunosensors and eye-based technologies have been described, showing detection times lower than 10 min after swab introduction. Alternative to swab-based techniques, lateral flow point-of-care immunoassays are already commercially available for the analysis of blood samples. Such biosensing devices hold the advantage of being portable for on-site testing in hospitals, airports, and hotspots, virtually without any sample treatment or complicated lab precautions.


Assuntos
Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Sistemas Automatizados de Assistência Junto ao Leito , Anticorpos Antivirais/sangue , Betacoronavirus/genética , Betacoronavirus/isolamento & purificação , Betacoronavirus/metabolismo , Técnicas Biossensoriais/métodos , Infecções por Coronavirus/virologia , Humanos , Imunoensaio/métodos , Pandemias , Pneumonia Viral/virologia , Proteômica/métodos , RNA Viral/análise , RNA Viral/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/métodos
13.
Hell J Nucl Med ; 23 Suppl: 8-14, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32860390

RESUMO

On December 2019, a new coronavirus disease (COVID-19) emerged in China and spread worldwide, causing acute severe respiratory syndrome. Due to the increased transmission rate of the virus, it became of great importance the early diagnosis of the disease. The coronavirus pandemic led to the development of numerous tests in order to mass screening population for active viral load and for the identification of antibodies for epidemiological purposes. This review summarizes the different diagnostic tests available to the clinicians for the diagnosis and follow up of the SARS COV-2 infections.


Assuntos
Infecções por Coronavirus/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Pneumonia Viral/diagnóstico , Radiografia Torácica/métodos , Técnicas de Cultura de Células/métodos , Infecções por Coronavirus/sangue , Infecções por Coronavirus/diagnóstico por imagem , Humanos , Imunoensaio/métodos , Imunoensaio/normas , Técnicas de Diagnóstico Molecular/normas , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/diagnóstico por imagem , Radiografia Torácica/normas , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Sensibilidade e Especificidade , Testes Sorológicos/métodos , Testes Sorológicos/normas
14.
BMC Res Notes ; 13(1): 372, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32762746

RESUMO

OBJECTIVE: COVID19 has caused a global and ongoing pandemic. The need for population seroconversion data is apparent to monitor and respond to the pandemic. Using a lateral flow assay (LFA) testing platform, the seropositivity in 63 New York Blood Center (NYBC) Convelescent Plasma (CP) donor samples were evaluated for the presence of COVID19 specific IgG and IgM. RESULTS: CP donors showed diverse antibody result. Convalescent donor plasma contains SARS-CoV-2 specific antibodies. Weak antibody bands may identify low titer CP donors. LFA tests can identify antibody positive individuals that have recovered from COVID19. Confirming suspected cases using antibody detection could help inform the patient and the community as to the relative risk to future exposure and a better understanding of disease exposure.


Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Betacoronavirus/imunologia , Doadores de Sangue , Técnicas de Laboratório Clínico/métodos , Convalescença , Infecções por Coronavirus/diagnóstico , Imunoensaio/métodos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Proteínas do Nucleocapsídeo/imunologia , Pandemias , Pneumonia Viral/diagnóstico , Testes Imediatos , Glicoproteína da Espícula de Coronavírus/imunologia , Especificidade de Anticorpos , Infecções por Coronavirus/terapia , Coloide de Ouro , Humanos , Imunização Passiva , Plasma , Domínios Proteicos , Proteínas Recombinantes/imunologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Soroconversão
15.
J Clin Virol ; 130: 104576, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32763810

RESUMO

BACKGROUND: The unsatisfactory accuracy and capacity of real time RT-PCR depends on several unavoidable reasons, which cannot meet the demands for COVID-19 diagnosis. METHODS: 206 serum samples were collected from patients who were treated in the General Hospital of the Central Theater Command of the PLA between January 18 and April 4, 2020. 270 serum samples from healthy blood donors were used as control. IgM and total antibodies (Ab) against SARS-CoV-2 were detected by Chemiluminescence Microparticle Immunoassay (CMIA). RESULTS: Among the 206 patients, the positive rate of IgM and Ab were 149/206 (72.3 %) and 187/206 (90.8 %), respectively. And the specificity of IgM and Ab detection were 99.3 % and 98.9 %, respectively. The sensitivity of CMIA for Ab detection was significantly higher than that of IgM. An increase of the positive rate and S/CO value for detecting IgM and Ab accompanied with the increasing of days post-disease onset (d.p.o.) were observed. The positive rate of Ab detected by CMIA increased rapidly after 7 d.p.o., while that of IgM was obviously increased after 14 d.p.o.. In addition, the age and gender of these patients did not affect the seroconversion and titer of antibodies during the whole course. The disease-severity of patients had no effect on the seroconversion of antibodies. However, the critical patients possessed a much higher antibody titers than the no-critical cases after 14 d.p.o.. CONCLUSIONS: The CMIA can provide important complementation to nucleic acid assay and help to enhance the accuracy and capacity of diagnosis of SARS-CoV-2 infection.


Assuntos
Anticorpos Antivirais/sangue , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Imunoensaio/métodos , Pneumonia Viral/diagnóstico , Adulto , Idoso , Betacoronavirus , Infecções por Coronavirus/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/imunologia , Sensibilidade e Especificidade , Soroconversão
16.
J Clin Virol ; 130: 104572, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32769024

RESUMO

BACKGROUND: The emergence of SARS-CoV-2 has led to the development of serological assays that could aid in an understanding of the burden of COVID-19 disease. Many available tests lack rigorous evaluation and therefore results may be misleading. OBJECTIVES: The aim of this study was to assess the performance of a novel multiplexed immunoassay for the simultaneous detection of antibodies against SARS-CoV-2 trimeric spike (S), spike receptor binding domain (RBD), spike N terminal domain and nucleocapsid antigen and a novel pseudo-neutralisation assay. METHODS: A multiplexed solid-phase chemiluminescence assay (Meso Scale Discovery) was evaluated for the simultaneous detection of IgG binding to four SARS-CoV-2 antigens and the quantification of antibody-induced ACE-2 binding inhibition (pseudo-neutralisation assay). Sensitivity was evaluated with a total of 196 COVID-19 serum samples (169 confirmed PCR positive and 27 anti-nucleocapsid IgG positive) from individuals with mild symptomatic or asymptomatic disease. Specificity was evaluated with 194 control serum samples collected from adults prior to December 2019. RESULTS: The specificity and sensitivity of the binding IgG assay was highest for S protein with a specificity of 97.4 % and sensitivity of 96.2 % for samples taken 14 days and 97.9 % for samples taken 21 days following the onset of symptoms. IgG concentration to S and RBD correlated strongly with percentage inhibition measured by the pseudo-neutralisation assay. CONCLUSION: Excellent sensitivity for IgG detection was obtained over 14 days since onset of symptoms for three SARS-CoV-2 antigens (S, RBD and N) in this multiplexed assay which can also measure antibody functionality.


Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Infecções por Coronavirus/diagnóstico , Imunoensaio/métodos , Imunoglobulina G/sangue , Pneumonia Viral/diagnóstico , Adulto , Betacoronavirus , Técnicas de Laboratório Clínico , Infecções por Coronavirus/imunologia , Feminino , Humanos , Medições Luminescentes/métodos , Masculino , Pessoa de Meia-Idade , Proteínas do Nucleocapsídeo/imunologia , Pandemias , Pneumonia Viral/imunologia , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus/imunologia
18.
PLoS One ; 15(8): e0237438, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790799

RESUMO

Rapid tests (RTs), also known as point-of-care tests, usually release results within 30 minutes with no need for a qualified staff, equipment, or laboratory structure. The Brazilian Ministry of Health published a resolution in 2013, recommending the use of RTs for the diagnosis of HIV infection, where one positive RT must be followed by another different RT. This was meant to increase the chance of proper diagnosis in specific settings and special populations. However, data comparing and validating the different HIV RTs available in Brazil are scarce. Therefore, the present study seeks to evaluate eight anti-HIV RTs available in the Brazilian market regarding their analytical performance: sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios, and accuracy. We also evaluated the agreement between kits (Kappa index) and the quality of the reading pattern of the tests. This was an observational, analytical, and concordance study, in which previously defined positive and negative samples, based on their serological pattern for anti-HIV antibodies (chemiluminescent immunoassay-ECLIA-used as screening and Western Blot used as the confirmatory test) were tested. Analytical performance and Kappa index were calculated, considering a 95% CI and p<0.05. This study identified differences in the performances of the eight tested kits. Six out of eight RTs showed good performance and can be used in the routine laboratory and health care units as screening tests. Regarding the quality of the RT band reading pattern, two brands had several samples showing quite faint bands, thus compromising its use in clinical and laboratory settings.


Assuntos
Infecções por HIV/diagnóstico , Imunoensaio/métodos , Anticorpos Anti-HIV/sangue , Humanos , Medições Luminescentes , Sistemas Automatizados de Assistência Junto ao Leito , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade
19.
Diagn Microbiol Infect Dis ; 98(3): 115141, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32795776

RESUMO

BACKGROUND: Kawasaki disease (KD) is an acute febrile and eruptive disease with systemic vasculitis predominantly affecting young East Asian children. Recent reports showed that children with KD-like disease from KD low prevalence regions had positive SARS-CoV-2 serology despite a negative SARS-CoV-2 polymerase chain reaction (PCR) in respiratory samples. OBJECTIVES: To describe 3 pediatric Kawasaki Disease patients with false positive SARS-CoV-2 serology. STUDY DESIGN: We retrospectively recruited children with KD diagnosed during the COVID-19 outbreak in Hong Kong. Clinical characteristics and laboratory test results including SARS-CoV-2 PCR results were retrieved. We performed a microparticle-based immunoassay for the detection of IgG against nucleoprotein (NP) and spike protein receptor binding domain (RBD), and a microneutralization assay for the detection of neutralizing antibodies. RESULTS: Three Chinese children with typical KD were identified. They had no epidemiological links with COVID-19 patients and tested negative for SARS-CoV-2 NPA PCR. They were treated with IVIG and aspirin, and were discharged without complications. Subsequently 2 of them were tested positive against anti-RBD and anti-NP antibodies and 1 was tested positive against anti- RBD antibodies. However, microneutralization assay showed that neutralizing antibodies were absent, suggesting a false-positive IgG result. CONCLUSION: Detection of neutralizing antibodies is recommended to confirm previous SARS-CoV-2 infection in IgG-positive but PCR-negative patients.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Infecções por Coronavirus/diagnóstico , Imunoensaio/métodos , Síndrome de Linfonodos Mucocutâneos/patologia , Pneumonia Viral/diagnóstico , Testes Sorológicos/métodos , Betacoronavirus/imunologia , Criança , Reações Falso-Positivas , Hong Kong , Humanos , Técnicas de Diagnóstico Molecular/métodos , Proteínas do Nucleocapsídeo/imunologia , Pandemias , Reação em Cadeia da Polimerase/métodos , Estudos Retrospectivos , Glicoproteína da Espícula de Coronavírus/imunologia
20.
Diagn Microbiol Infect Dis ; 98(3): 115140, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32829098

RESUMO

INTRODUCTION: SARS-CoV-2 seroconversion is important for epidemiological studies as well as contact tracing. MATERIAL AND METHODS: The antibody response against SARS-CoV-2 was examined in 111 patients with a positive qRT-PCR. Seroconversion was assessed using the Elecsys from Roche, the Liaison S1/S2 IgG from Diasorin, the IgG and IgA from Euroimmun, as well as the VIDAS IgG and IgM. Specificity was estimated based on the measurement of SARS-CoV-2 antibodies in 96 residual samples collected during a non-pandemic period. RESULTS: The highest overall sensitivity for detecting seroconversion was obtained using the Elecsys (81.1%), the Euroimmun with a combined detection of IgG/IgA (86.5%), and the VIDAS with a simultaneous measurement of IgG/IgM (78.4%).The Elecsys and the VIDAS IgG/IgM demonstrated a specificity as well as a positive predictive value of 100%. CONCLUSIONS: The Elecsys and the VIDAS methods with a combination of IgG/IgM measurement demonstrated a high sensitivity with no false positive results.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Feminino , Humanos , Imunoensaio/métodos , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Masculino , Pessoa de Meia-Idade , Pandemias , Reação em Cadeia da Polimerase , Soroconversão , Testes Sorológicos/métodos , Adulto Jovem
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