The Shift to Over-the-Counter Diagnostic Testing After RADx: Clinical, Regulatory, and Societal Implications.

COVID-19 Preoperative Assessment and Testing: From Surge to Recovery.

Evaluating tests for diagnosing COVID-19 in the absence of a reliable reference standard: pitfalls and potential solutions

To predict COVID-19 disease severity within 10 days, distinguishing cases that will progress to moderate or severe versus mild, patient urinary L-type fatty acid-binding protein (L-FABP) was assayed within 4 days of receiving a diagnosis. The study also examined whether L-FABP point of care (POC) test is helpful in risk screening. Symptomatic subjects who tested positive for SARS-CoV-2 and were hospitalized were prospectively enrolled at the National Center for Global Health and Medicine (NCGM), Yamanashi Prefectural Central Hospital (YPCH), and Sinai Hospital in Maryland. The outcome of each case was evaluated 7 days after admission and the diagnostic performance of L-FABP was assessed. Subjects were treated for COVID-19 at public healthcare centers in Japan from January 31, 2020, to January 31, 2021, to NCGM, YPCH, and at Sinai Hospital in Baltimore, MD, during the same period. The primary outcome was to determine whether urinary L-FABP within 48 hours of admission can predict the patient's severity of COVID-19 1 week later. We obtained demographic data, information on clinical symptoms, radiographic images, and laboratory data. Diagnostic performance was assessed using receiver operating characteristic analysis. Of the 224 participants in the study, 173 initially had a mild form of COVID-19. The area under the curve (AUC) for a severe outcome was 93.5%. L-FABP POC risk prediction of a severe outcome had an AUC of 88.9%. Urinary L-FABP can predict patient risk of COVID-19 illness severity. L-FABP POC is implementable for patient management. (ClinicalTrials.gov number, NCT04681040).

This study aims to apply machine learning models to identify new biomarkers associated with the early diagnosis and prognosis of SARS-CoV-2 infection.Plasma and serum samples from COVID-19 patients (mild, moderate, and severe), patients with other pneumonia (but with negative COVID-19 RT-PCR), and healthy volunteers (control) from hospitals in four different countries (China, Spain, France, and Italy) were analyzed by GC-MS, LC-MS, and NMR. Machine learning models (PCA and PLS-DA) were developed to predict the diagnosis and prognosis of COVID-19 and identify biomarkers associated with these outcomes.A total of 1410 patient samples were analyzed. The PLS-DA model presented a diagnostic and prognostic accuracy of around 95% of all analyzed data. A total of 23 biomarkers (e.g., spermidine, taurine, L-aspartic, L-glutamic, L-phenylalanine and xanthine, ornithine, and ribothimidine) have been identified as being associated with the diagnosis and prognosis of COVID-19. Additionally, we also identified for the first time five new biomarkers (N-Acetyl-4-O-acetylneuraminic acid, N-Acetyl-L-Alanine, N-Acetyltriptophan, palmitoylcarnitine, and glycerol 1-myristate) that are also associated with the severity and diagnosis of COVID-19. These five new biomarkers were elevated in severe COVID-19 patients compared to patients with mild disease or healthy volunteers.The PLS-DA model was able to predict the diagnosis and prognosis of COVID-19 around 95%. Additionally, our investigation pinpointed five novel potential biomarkers linked to the diagnosis and prognosis of COVID-19: N-Acetyl-4-O-acetylneuraminic acid, N-Acetyl-L-Alanine, N-Acetyltriptophan, palmitoylcarnitine, and glycerol 1-myristate. These biomarkers exhibited heightened levels in severe COVID-19 patients compared to those with mild COVID-19 or healthy volunteers.

Screening for colorectal cancer: confuting the refuters

The authors assess the costs associated with treatment of dyspepsia with histamine2 antagonists versus without availability of over-the-counter (OTC). A cost analysis was performed using a decision-analysis model. Patients with an initial episode of dyspepsia were studied. The model includes costs associated with consumption of OTC and prescription (Rx) medications for dyspepsia, physician visits and associated diagnostic testing, time spent for physician visits and diagnostic tests, and hospitalization costs. The model is sensitive to the relative cost of histamine2 antagonists when purchased Rx or OTC, as well as to the efficacy of these drugs in relieving dyspeptic symptoms. For patients with nonulcer dyspepsia (the largest group of likely consumers), the model demonstrates a cost savings if the OTC cost of the medication is slightly less than one third the Rx cost. Costs are similar whether or not histamine2 antagonists are available OTC. If the symptom relief efficacies of histamine2 antagonists are equivalent whether purchased by prescription only or OTC, then the health-care expenditures for a typical patient with dyspepsia are $204 for OTC availability and $203 for Rx-only use. Viewing costs from the perspective of a managed-care organization, expenditures for an episode of dyspepsia are $149 regardless of whether or not histamine2 antagonists are available OTC. Restricting the analysis to patients with underlying nonulcer dyspepsia yields similar results. Variation of numerous assumptions and probabilities other than histamine antagonist cost and efficacy, including costs associated with physician visits and diagnostic tests, and the likelihood of seeking medical care, do not substantially affect the results of the model. Health-care costs associated with initial treatment of dyspepsia are similar regardless of the availability of histamine2 antagonists OTC. This is due largely to the similar efficacy of these drugs compared with antacids and the predicted increase in diagnostic testing that may result if a patient visits a physician after failure to achieve symptom relief with OTC use of histamine2 antagonists.

DIAGNOSTIC TESTING FOR COVID-19 infections is one of the linchpins of the global effort to combat the deadly pandemic. But the strategy normally used for that has a few downsides. For one, the nasopharyngeal swabbing required demands the services of a health care worker, who is then put at risk of contracting the disease. Also, the sample-taking procedure, which involves sticking a very long flexible swab through a nostril and into the nasopharynx at the back of the nose and throat, is so unpleasant that some people resist being tested. And because the samples must normally be sent to a distant lab for processing, it often takes hours to days for results to become available. (1) What the world desperately needs is a way to diagnose infections with the virus more quickly and easily. Breakthroughs here would allow for truly widespread testing and the identification of people with asymptomatic infections, who often inadvertently spread the disease. (2) Researchers across the world have been racing to develop better COVID-19 tests, and biochemists and molecular biologists have made significant progress in just a handful of months. But engineers, too, have been working on technologies that might provide what everyone so dearly wants: inexpensive tests that don't require swabbing and that can be rapidly performed by anyone, anywhere - if not for this pandemic, then perhaps in time for the next one.

The current COVID-19 pandemic presents a serious public health crisis, and a better understanding of the scope and spread of the virus would be aided by more widespread testing. Nucleic-acid-based tests currently offer the most sensitive and early detection of COVID-19. However, the “gold standard” test pioneered by the U.S. Centers for Disease Control and Prevention takes several hours to complete and requires extensive human labor, materials such as RNA extraction kits that could become in short supply, and relatively scarce qPCR machines. It is clear that a huge effort needs to be made to scale up current COVID-19 testing by orders of magnitude. There is thus a pressing need to evaluate alternative protocols, reagents, and approaches to allow nucleic-acid testing to continue in the face of these potential shortages. There has been a tremendous explosion in the number of papers written within the first weeks of the pandemic evaluating potential advances, comparable reagents, and alternatives to the “gold-standard” CDC RT-PCR test. Here we present a collection of these recent advances in COVID-19 nucleic acid testing, including both peer-reviewed and preprint articles. Due to the rapid developments during this crisis, we have included as many publications as possible, but many of the cited sources have not yet been peer-reviewed, so we urge researchers to further validate results in their own laboratories. We hope that this review can urgently consolidate and disseminate information to aid researchers in designing and implementing optimized COVID-19 testing protocols to increase the availability, accuracy, and speed of widespread COVID-19 testing.

Objective In view of the difficulty of the shortage of new coronavirus nucleal acid test in the early COVID-19 outbreak, to explore the application value of chest CT in screening COVID-19 patients. Methods Retrospective analysis was performed on the data of patients with fever who received chest CT and new coronavirus nucleal acid test during January 25, 2020 to February 2, 2020 in Zhongnan Hospital of Wuhan University. A total of 587 patients were enrolled, including 290 males and 297 females, aged from 11.0 to 96.0 (51.3±17.1) years old. Take the nucleic acid test results as the gold standard, the sensitivity, specificity and rate of missed diagnosis of CT screening COVID-19 were calculated. Results Among the 587 patients, there were 433 positive cases (73.8%, 433/587) and 154 negative cases (26.2%, 154/587) of novel coronavirus nucleic acid test. Using CT screening, 494 cases (84.2%, 494/587) were positive and 93 cases (15.8%, 93/587) were negative. The sensitivity of CT screening COVID-19 was 97.7% (423/433), specificity was 53.9% (83/154) and rate of missed diagnosis was 2.3% (10/433). Conclusions In the early COVID-19 outbreak, CT screening has the advantages of high sensitivity and low rate of missed diagnosis of COVID-19, which can compensate for the shortage of new coronavirus nucleal acid test and can be used as the basis for rapid screening for early prevention and control of COVID-19 outbreak. Key words: COVID-19; Tomography, X-ray computed; Diagnostic test; Sensitivity

BackgroundThe management of the COVID-19 pandemic is hampered by the long delays associated with laboratory PCR testing. In hospitals this leads to poor patient flow and nosocomial transmission and so rapid, accurate diagnostic tests are urgently required. The aim of this study was to evaluate the clinical impact and real-world diagnostic accuracy of molecular point-of-care testing (mPOCT) for COVID-19 in hospital.MethodsWe performed a prospective, interventional, non-randomised, controlled study of mPOCT for COVID-19 in adults presenting to hospital with suspected COVID-19. Patients were tested using the QIAstat-Dx SARS-CoV-2 at the point-of-care with results delivered to clinical and infection control teams. Control patients were tested using the PHE Rdrp reference assay. The Primary outcome measure was time to result and secondary outcome measures included infection control outcomes and measures of diagnostic accuracy.ResultsBetween 20th March and 29th April 2020 500 patients were tested by POCT and 555 controls, who were tested with laboratory PCR, were identified. Overall 33% were positive for SARS-CoV-2. Median time to results with POCT was 1.7 (1.6 to 1.9) hours versus 21.3 (16.0 to 27.9) hours in the control group (difference of 19.6 hours, 95%CI 19.0 to 20.3; p< 0.0001). Median time to arrival in definitive clinical area (COVID-19 positive or negative ward) was 8.0 (6.0 to 15.0) hours in the POCT group versus 28.8 (23.5 to 38.9) hours in the control group, p< 0.0001. Median time to enrolment into other COVID-19 clinical trials was 1.5 (1 to 3) days in the POCT versus 3.0 (2 to 5) days in the control group, p< 0.0001. Sensitivity of the POCT was 99.4% and specificity was 98.3%. The sensitivity of the laboratory PHE reference RdRp assay was 87.2% and specificity was 98.9%.ConclusionmPOCT was associated with a large reduction in time to results and improvements in infection control measures and patient flow, compared with laboratory PCR. In addition, patients were recruited onto other clinical trials more rapidly with POCT. The QIAstat-Dx SARS-CoV-2 panel had high diagnostic accuracy for the detection of COVID-19 compared to laboratory PCR. Resources should be urgently made available to support the widespread implementation of mPOCT in hospitals, in preparation for the second wave.DisclosuresTristan William. Clark, BM MRCP DTM&H MD, BioFire Diagnostics (Other Financial or Material Support, Equiptment and consumables for the purposes of research)BioMerieux (Other Financial or Material Support, Equipment and consumables for the purposes of research)Qiagen (Other Financial or Material Support, Discounted Equipment and consumables for the purposes of research)

Severe acute respiratory syndrome coronavirus 2 screening to augment dental office and patient safety

Clinical microbiology laboratories in low-resource settings, it is not only about equipment and reagents, but also good governance for sustainability

Health literacy characteristics of over-the-counter rapid antigen COVID-19 test materials

Recent advances in nanomaterials based biosensors for point of care (PoC) diagnosis of Covid-19 – A minireview

O SARS-CoV-2 é um novo vírus de origem desconhecida que surgiu na China em dezembro de 2019. A realização do diagnóstico é complexa e envolve a necessidade de compreensão quanto aos tipos de testes e suas peculiaridades. Há dois testes diagnósticos disponíveis no momento: o molecular e o imunológico (também chamado sorológico). Cada um possui as suas características específicas. Diante desse contexto, o presente trabalho teve como objetivo descrever os aspectos gerais das técnicas empregadas no diagnóstico da COVID-19. Trata-se de um estudo de revisão bibliográfica de cunho descritivo e com abordagem quantitativa nas bases de dados do Scielo, Lilacs, Google Acadêmico e através do Portal de Pesquisa da Biblioteca Virtual em Saúde (BVS). A sensibilidade dos testes para detecção de anticorpos por diferentes técnicas variou entre 81,5% e 88,6%, e a especificidade variou entre 90,6% e 100%. Estudos avaliando a sensibilidade do RT-PCR em relação a critérios diagnósticos identificaram sensibilidade de 44,2% para amostras coletadas por swab de orofaringe e 76,9% quando a amostra utilizada foi o escarro. A avaliação da acurácia diagnóstica de testes de amplificação de partículas virais aplicados na modalidade point-of-care evidenciou sensibilidade de 90% e especificidade de 100%, em relação ao RT-PCR. Os testes sorológicos, parecem apresentar boa sensibilidade e especificidade, quando aplicados em fase mais tardia da infecção. Em fases precoces da infecção, apresentam alta taxa de resultados falsos negativos. Entretanto, até à presente data é indicado a realização do teste de RT-PCR para o diagnóstico definitivo da COVID-19.