scholarly journals Analytical sensitivity of seven SARS-CoV-2 antigen-detecting rapid tests for Omicron variant

2021 ◽  
Author(s):  
Meriem Bekliz ◽  
Kenneth Adea ◽  
Catia Alvarez ◽  
Manel Essaidi-Laziosi ◽  
Camille Escadafal ◽  
...  
Keyword(s):  
Diagnostic Performance ◽  
Published Data ◽  
Lower Sensitivity ◽  
Analytical Sensitivity ◽  
Sensitivity Testing ◽  
Clinical Sensitivity ◽  
Clinical Evaluations ◽  
Rapid Tests ◽  
Alpha Beta ◽  
Potential Impact

The emergence of novel SARS-CoV-2 variants of concern (VOCs) requires investigation of a potential impact on diagnostic performance, especially on Antigen-detecting rapid antigenic tests (Ag-RDT). Although anecdotal reports have been circulating that Omicron is in principle detected by several Ag-RDTs, no published data are a yet available for the newly emerged Omicron variant. Here, we have performed an analytical sensitivity testing with cultured virus in seven Ag-RDTs for their sensitivity to Omicron compared to data earlier obtained on VOCs Alpha, Beta Gamma and Delta and a pre-VOC isolate of SARS-CoV-2. Overall, we have found a tendency towards lower sensitivity for Omicron compared to pre-VOC SARS-CoV-2 and the other VOCs across tests. Importantly, while analytical testing with cultured virus may be a proxy for clinical sensitivity, is not a replacement for clinical evaluations which are urgently needed for Ag-RDT performance in Omicron-infected individuals.

scholarly journals Analytical performance of eleven SARS-CoV-2 antigen-detecting rapid tests for Delta variant

2021 ◽  
Author(s):  
Meriem Bekliz ◽  
Kenneth Adea ◽  
Manel Essaidi-Laziosi ◽  
Camille Escadafal ◽  
Jilian Sacks ◽  
...  
Keyword(s):  
Diagnostic Tests ◽  
Diagnostic Performance ◽  
Rapid Diagnostic Tests ◽  
Analytical Performance ◽  
Rapid Tests ◽  
Alpha Beta ◽  
Few Data

Global concerns arose as the emerged and rapidly spreading SARS-CoV-2 Delta variant. To date, few data on routine diagnostic performance for Delta are available. Here, we investigate the analytical performance of eleven commercially available antigen-detecting rapid diagnostic tests (Ag-RDTs) for Delta VOC in comparison with current and earlier VOCs (Alpha, Beta and Gamma) and early pandemic variant using cultured SARS-CoV-2. Comparable sensitivity was observed for Delta for the majority of Ag-RDTs.

Neuroblastoma—When are Urinary Catecholamines and Their Metabolites ‘Normal’?

1988 ◽  
Vol 25 (6) ◽  
pp. 620-626 ◽  
Author(s):  
D J Worthington ◽  
E M Hammond ◽  
B B Eldeeb ◽  
A Green ◽  
G M Addison ◽  
...  
Keyword(s):  
Urinary Excretion ◽  
The Other ◽  
Published Data ◽  
Single Test ◽  
Creatinine Concentration ◽  
Urinary Catecholamines ◽  
Clinical Sensitivity ◽  
Reference Limit ◽  
Upper Reference Limit ◽  
The Individual

The overproduction of catecholamines and their metabolites is a well recognised feature of neuroblastoma. Published data are scarce for their urinary excretion in children with neuroblastoma and in ill children in whom this diagnosis may be considered. We have determined a graphical upper reference limit for total catecholamines, total metadrenalines and HMMA in urine, expressed as a ratio to the creatinine concentration, for a group of 174 children with neuroblastoma and 704 hospitalised children with other disorders. This graph has been determined by examining the overlap region between the results for the two groups of children and avoids the irregularities caused by statistical outliers. The sensitivity and specificity of the individual tests indicate that total catecholamines is marginally the best single test to perform when trying to diagnose neuroblastoma, with the best clinical sensitivity being achieved by examining both total catecholamines and HMMA. Only two of the 174 children with neuroblastoma would not have been detected using these two tests. Total metadrenalines did not appear to add any further information and could be dropped from the repertoire in favour of the other two measurements.

scholarly journals The Potential Impact of Up-Front Drug Sensitivity Testing on India’s Epidemic of Multi-Drug Resistant Tuberculosis

PLoS ONE ◽  
2015 ◽  
Vol 10 (7) ◽  
pp. e0131438 ◽  
Author(s):  
Kuldeep Singh Sachdeva ◽  
Neeraj Raizada ◽  
Radhey Shyam Gupta ◽  
Sreenivas Achuthan Nair ◽  
Claudia Denkinger ◽  
...  
Keyword(s):  
Drug Sensitivity ◽  
Drug Resistant ◽  
Sensitivity Testing ◽  
Drug Resistant Tuberculosis ◽  
Drug Sensitivity Testing ◽  
Resistant Tuberculosis ◽  
Multi Drug Resistant Tuberculosis ◽  
Potential Impact

A prospective nationwide observational study of agreement of antigen tests on oral pharyngeal swabs or less invasive testing with RT-qPCR, for detecting SARS-CoV-2 in adults: Protocol description (Preprint)

2021 ◽  
Author(s):  
Uffe Vest Schneider ◽  
Jenny Dahl Knudsen ◽  
Anders Koch ◽  
Nikolai Søren Kirkby ◽  
Jan Gorm Lisby
Keyword(s):  
Confidence Intervals ◽  
Predictive Value ◽  
Large Scale ◽  
Reference Method ◽  
Lateral Flow ◽  
Clinical Samples ◽  
Sampling Location ◽  
Analytical Sensitivity ◽  
Clinical Sensitivity ◽  
Antigen Tests

BACKGROUND The SARS-CoV-2 pandemic has resulted in an unprecedented level of world-wide testing for epidemiologic and diagnostic purposes, and due to the extreme need for tests, the gold standard reverse transcription polymerase chain reaction (RT-qPCR) testing capacity has been unable to meet the overall global testing demand. Consequently, although current literature has shown the sensitivity of rapid antigen tests (RATs) to be inferior to RT-qPCR, RATs have been implemented on a large scale without solid data on performance. OBJECTIVE This study will compare analytical and clinical sensitivities and specificities of 50 lateral flow or laboratory based RATs and three Strand Invasion Based Amplification (SIBA)-rt-PCR tests from 30 manufacturers to RT-qPCR on samples obtained from the deep oropharynx. In addition, the study will compare sensitivities and specificities of the included RATs as well as RT-qPCR on clinical samples obtained from the deep oropharynx, anterior nasal cavity, saliva, deep nasopharynx and expired air to RT-qPCR from deep oropharyngeal samples. METHODS In the prospective part of the study, 200 individuals found SARS-CoV-2 positive and 200 individuals found SARS-CoV-2 negative by routine RT-qPCR testing will be re-tested with each RAT applying RT-qPCR as the reference method. In the retrospective part of the study, 304 deep oropharyngeal cavity swabs divided into four groups based on RT-qPCR Cq levels will be tested by each RAT. RESULTS The results will be reported in several manuscripts with different aims. The first manuscript will report retrospective (analytical sensitivity, overall and stratified into different Cq range groups) and prospective (clinical sensitivity) data for RATs with RT-qPCR results as the reference method. The second manuscript will report results for RAT based on anatomical sampling location. The third manuscript will compare different anatomical sampling locations by RT-qPCR testing. The fourth manuscript will focus on RATs that rely on central laboratory testing. Test from four different manufactures will be compared for analytical performance data on retrospective deep oropharyngeal swab samples. The fifth manuscript will report the results of four RATs applied both as professional use and as self-test. The last manuscript will report the results from two breath tests participating in the study. Comparison of sensitivity and specificity between RATs will be done using McNemar for paired samples and chi-squared test for unpaired samples. Comparison of PPV and NPV between RATs will be done by bootstrap test. 95 % confidence intervals for sensitivity, specificity, positive predictive value and negative predictive value are calculated as bootstrap confidence intervals CONCLUSIONS The study will compare the sensitivities of a large number of RATs for SARS-CoV-2 compared to RT-qPCR and will address whether lateral flow based RATs test differ significantly from laboratory based RATS. The anatomical test location for both RAT and RT-qPCR will be compared. CLINICALTRIAL ClinicalTrials.gov NCT04913116

How much do periventricular lesions assist in distinguishing migraine with aura from CIS?

Neurology ◽  
2019 ◽  
Vol 92 (15) ◽  
pp. e1739-e1744 ◽  
Author(s):  
Caterina Lapucci ◽  
Laura Saitta ◽  
Giulia Bommarito ◽  
Maria Pia Sormani ◽  
Matteo Pardini ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Migraine With Aura ◽  
Diagnostic Performance ◽  
White Matter Hyperintensities ◽  
Clinically Isolated Syndrome ◽  
Lower Sensitivity ◽  
Resonance Imaging ◽  
Future Studies ◽  
Periventricular Lesions

ObjectiveTo evaluate in clinically isolated syndrome (CIS) and migraine with aura (MA) how the number of periventricular lesions (PVLs) detected at MRI influences diagnostic performance when the Magnetic Resonance Imaging in Multiple Sclerosis (MAGNIMS) or the 2017 revised criteria are applied.MethodsIn this retrospective study, white matter hyperintensities (WMH) of 84 patients with MA and 79 patients with CIS were assessed using manual segmentation technique. Lesion probability maps (LPMs) and voxel-wise analysis of lesion distribution by diagnosis were obtained. Furthermore, we performed a logistic regression analysis based on lesion locations and volumes.ResultsCompared to patients with MA, patients with CIS showed a significant overall higher T2 WMH mean number and volume (17.9 ± 16.9 vs 6.2 ± 11.9 and 3.1 ± 4.2 vs 0.3 ± 0.6 mL; p < 0.0001) and a significantly higher T2 WMH mean number in infratentorial, periventricular, and juxtacortical areas (p < 0.0001). LPMs identified the periventricular regions as the sites with the highest probability of detecting T2 WMH in patients with CIS. Voxel-wise analysis of lesion distribution by diagnosis revealed a statistically significant association exclusively between the diagnosis of CIS and the PVLs. MAGNIMS criteria demonstrated the highest specificity in differentiating patients with CIS from patients with MA (100% vs 87%) against a predictable lower sensitivity (63% vs 72%).ConclusionsPVLs play a key role in the differential diagnosis between MA and CIS, particularly when there are more than 3. Future studies on multiple sclerosis criteria might reconsider the 3 PVLs to minimize the risk of misdiagnosis.Classification of evidenceThis study provides Class IV evidence that the presence at least 3 PVLs increases the specificity in distinguishing MA from CIS.

scholarly journals FET PET Radiomics for Differentiating Pseudoprogression from Early Tumor Progression in Glioma Patients Post-Chemoradiation

Cancers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3835
Author(s):  
Philipp Lohmann ◽  
Mai A. Elahmadawy ◽  
Robin Gutsche ◽  
Jan-Michael Werner ◽  
Elena K. Bauer ◽  
...  
Keyword(s):  
Tumor Progression ◽  
Negative Predictive Value ◽  
Predictive Value ◽  
Diagnostic Performance ◽  
Data Augmentation ◽  
Response Assessment ◽  
Lower Sensitivity ◽  
Fet Pet ◽  
Early Tumor ◽  
Dynamic Fet Pet

Currently, a reliable diagnostic test for differentiating pseudoprogression from early tumor progression is lacking. We explored the potential of O-(2-[18F]fluoroethyl)-L-tyrosine (FET) positron emission tomography (PET) radiomics for this clinically important task. Thirty-four patients (isocitrate dehydrogenase (IDH)-wildtype glioblastoma, 94%) with progressive magnetic resonance imaging (MRI) changes according to the Response Assessment in Neuro-Oncology (RANO) criteria within the first 12 weeks after completing temozolomide chemoradiation underwent a dynamic FET PET scan. Static and dynamic FET PET parameters were calculated. For radiomics analysis, the number of datasets was increased to 102 using data augmentation. After randomly assigning patients to a training and test dataset, 944 features were calculated on unfiltered and filtered images. The number of features for model generation was limited to four to avoid data overfitting. Eighteen patients were diagnosed with early tumor progression, and 16 patients had pseudoprogression. The FET PET radiomics model correctly diagnosed pseudoprogression in all test cohort patients (sensitivity, 100%; negative predictive value, 100%). In contrast, the diagnostic performance of the best FET PET parameter (TBRmax) was lower (sensitivity, 81%; negative predictive value, 80%). The results suggest that FET PET radiomics helps diagnose patients with pseudoprogression with a high diagnostic performance. Given the clinical significance, further studies are warranted.

The role of precision in determining the performance of a thyrotropin assay in diagnosing hyperthyroidism.

1988 ◽  
Vol 34 (7) ◽  
pp. 1464-1467 ◽  
Author(s):  
T J Wilke ◽  
D J Utley
Keyword(s):  
Lower Limit ◽  
Diagnostic Performance ◽  
Reference Interval ◽  
Major Determinant ◽  
Analytical Sensitivity ◽  
Diagnostic Efficiency ◽  
Immunometric Assay ◽  
Coefficients Of Variations ◽  
The Relationship

Abstract We examined the relationship between analytical sensitivity, precision at the lower limit of the reference interval, and diagnostic performance in hyperthyroidism for one radioimmunoassay and five immunometric assay kits for thyrotropin. The analytical sensitivity of these kits extended from 0.05 to 1.56 milli-int. units/L. Diagnostic efficiencies of the immunometric assays, in discriminating between euthyroidism and hyperthyroidism, ranged between 93% and 98%. There was a highly significant correlation (r = 0.99, P less than 0.001) between analytical sensitivity and diagnostic efficiency. The between-assay coefficients of variations, at the lower limit of the reference interval, ranged from 26% to 87%. There was no correlation (r = 0.36) between precision, at this concentration, and diagnostic efficiency. We conclude that analytical sensitivity and not precision is the major determinant in controlling the diagnostic performance of a thyrotropin assay in hyperthyroidism.

scholarly journals Taller-Than-Wide Shape: A New Definition Improves the Specificity of TIRADS Systems

2019 ◽  
Vol 9 (2) ◽  
pp. 85-91 ◽  
Author(s):  
Giorgio Grani ◽  
Livia Lamartina ◽  
Valeria Ramundo ◽  
Rosa Falcone ◽  
Cristiano Lomonaco ◽  
...  
Keyword(s):  
Risk Stratification ◽  
Diagnostic Performance ◽  
Thyroid Nodules ◽  
Negative Impact ◽  
Lower Sensitivity ◽  
Intraobserver Variability ◽  
Transverse Diameter ◽  
American Thyroid Association ◽  
Alternative Definition ◽  
The Impact

Introduction: A taller-than-wide (TTW) shape is a suspicious feature of thyroid nodules commonly defined as an anteroposterior/transverse diameter (AP/T) ratio >1. An intraobserver variability of up to 18% in AP diameter evaluations has been described, which may lead to overreporting of this feature. To potentially improve the reliability of the TTW definition, we propose an arbitrary ratio of ≥1.2. Objective: The aim of this study was to estimate the impact of this definition on diagnostic performance. Methods: We prospectively analyzed 553 thyroid nodules referred for cytology evaluation at an academic center. Before fine-needle aspiration, two examiners jointly defined all sonographic features considered in risk stratification systems developed by the American Thyroid Association (ATA), the American Association of Clinical Endocrinologists (AACE), the American College of Radiology (ACR TIRADS), the European Thyroid Association (EU-TIRADS), and the Korean Society of Thyroid Radiology (K-TIRADS). TTW was defined according to the current definition (AP/T diameter ratio >1) and an arbitrary alternative definition (AP/T ratio >1.2). Results: The alternative definition classified fewer nodules as TTW (28, 5.1% vs. 94, 17%). The current and proposed definitions have a sensitivity of 26.2 and 11.9% (p = 0.03) and a specificity of 83.8 and 95.5% (p < 0.001). Thus, as a single feature, the arbitrary definition has a lower sensitivity and a higher specificity. When applied to sonographic risk stratification systems, however, the proposed definition would increase the number of avoided biopsies (up to 58.2% for ACR TIRADS) and the specificity of all systems, without negative impact on sensitivity or diagnostic odds ratio. Conclusions: Re-defining TTW nodules as those with an AP/T ratio ≥1.2 improves this marker’s specificity for malignancy. Using this definition in risk stratification systems will increase their specificity, reducing the number of suggested biopsies without significantly diminishing their overall diagnostic performance.

scholarly journals The epidemiology of mumps in the UK: a preliminary study of virus transmission, herd immunity and the potential impact of immunization

1987 ◽  
Vol 99 (1) ◽  
pp. 65-84 ◽  
Author(s):  
R. M. Anderson ◽  
J. A. Crombie ◽  
B. T. Grenfell
Keyword(s):  
Herd Immunity ◽  
Virus Transmission ◽  
Epidemiological Data ◽  
Mumps Virus ◽  
Mass Vaccination ◽  
Vaccine Uptake ◽  
Published Data ◽  
Epidemic Period ◽  
Potential Impact ◽  
Mumps Infection

SUMMARYMathematical models and statistical analyses of epidemiological data are employed to assess the potential impact of mass vaccination on the incidences of cases of mumps infection and cases of mumps related complications. The analyses reveal that in the United Kingdom the average age at infection with the mumps virus is currently between 6–7 years and that the inter-epidemic period of the infection is approximately 3 years. The critical level of vaccine uptake to eliminate mumps virus transmission is predicted to be approximately 85% of each cohort of boys and girls by the age of 2 years. Analyses of published data show that the risk of complication arising from mumps infection is markedly age- and sex-related. Model predictions suggest that the incidence of orchitis will be increased, over the level pertaining prior to mass vaccination, by levels of vaccine uptake (by 2 years of age) that are less than 70% of each yearly cohort of boys and girls. Moderate (over 00%) to high (75%) levels of vaccine uptake, however, are predicted to reduce the overall incidence of cases of mumps related complications (especially those with CNS involvement).

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