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1.
J Extra Corpor Technol ; 53(1): 57-61, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33814607

RESUMEN

Heparin anticoagulation monitoring by point-of-care activated clotting time (ACT) is essential for cardiopulmonary bypass (CPB) initiation, maintenance, and anticoagulant reversal. Concerns exist regarding the comparability of kaolin activated ACT devices. The current study, therefore, evaluated the agreement of ACT assays using parallel measurements performed on two commonly used devices. Measurements were conducted in a split-sample fashion on both the ACT Plus (Medtronic, Minneapolis, MN) and i-STAT (Abbott Point of Care, Princeton, NJ) analyzers. Blood samples from 100 adult patients undergoing elective cardiac surgery with CPB were assayed at specified time points: before heparinization, following systemic heparinization, after CPB initiation, every 30 minutes during CPB, and following protamine administration. A cutoff value of 400 seconds (s) was used as part of the local protocol. Measurements were compared using t tests or Wilcoxon signed-rank tests, linear regression, and Bland-Altman analyses. Parallel ACT measurements demonstrated a good linear correlation (r = .831, p < .001). The overall median difference between both measurements was significantly different from zero, amounting to 87 (14-189) (p < .001), with limits of agreement of -124 and 333s. The i-STAT-derived ACT values were systematically lower than the ACT Plus values, which was more pronounced during CPB. Fourteen patients received additional heparin during CPB at a median ACT Plus value of 414s, with a concomitant median i-STAT value of 316s. Assuming 308s as the theoretical i-STAT cutoff value based on the linear regression equation and an ACT Plus threshold of 400s, 29 patients would have received additional heparin. Based on these results, kaolin point-of-care ACT devices cannot be used interchangeably. Device-specific predefined target values are warranted to avert heparin overdosing during CPB.


Asunto(s)
Caolín , Sistemas de Atención de Punto , Adulto , Anticoagulantes , Pruebas de Coagulación Sanguínea , Puente Cardiopulmonar , Heparina , Humanos , Tiempo de Coagulación de la Sangre Total
2.
PLoS One ; 16(3): e0248729, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33725025

RESUMEN

BACKGROUND: As COVID-19 vaccines become available, screening individuals for prior COVID-19 infection and vaccine response in point-of-care (POC) settings has renewed interest. We prospectively screened at-risk individuals for SARS-CoV-2 spike and nucleocapsid protein antibodies in a POC setting to determine if it was a feasible method to identify antibody from prior infection. METHODS: Three EUA-approved lateral flow antibody assays were performed on POC finger-stick blood and compared with serum and a CLIA nucleocapsid antibody immunoassay. Variables including antibody class, time since PCR, and the assay antigen used were evaluated. RESULTS: 512 subjects enrolled, of which 104 had a COVID-19 history and positive PCR. Only three PCR-positive subjects required hospitalization, with one requiring mechanical ventilation. The POC results correlated well with the immunoassay (93-97% sensitivity) and using serum did not improve the sensitivity or specificity. CONCLUSIONS: Finger-stick, POC COVID-19 antibody testing was highly effective in identifying antibody resulting from prior infections in mildly symptomatic subjects. Using high-complexity serum immunoassays did not improve the screening outcome. Almost all individuals with COVID-19 infection produced detectable antibodies to the virus. POC antibody testing is useful as a screen for prior COVID-19 infection, and should be useful in assessing vaccine response.


Asunto(s)
/diagnóstico , Sistemas de Atención de Punto , Adulto , Anciano , Anticuerpos Antivirales/sangre , Femenino , Humanos , Inmunoensayo , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Masculino , Persona de Mediana Edad , Nucleocápside/inmunología , Juego de Reactivos para Diagnóstico , /aislamiento & purificación , Sensibilidad y Especificidad , Adulto Joven
4.
Anal Chem ; 93(9): 4154-4159, 2021 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-33645217

RESUMEN

Chip-scale SARS-CoV-2 testing was demonstrated using silicon nitride (Si3N4) nanoslot fluidic waveguides to detect a tagged oligonucleotide with a coronavirus DNA sequence. The slot waveguides were fabricated using complementary metal-oxide-semiconductor (CMOS) fabrication processes, including multiscale lithography and selective reactive ion etching (RIE), forming femtoliter fluidic channels. Finite difference method (FDM) simulation was used to calculate the optical field distribution of the waveguide mode when the waveguide sensor was excited by transverse electric (TE) and transverse magnetic (TM) polarized light. For the TE polarization, a strong optical field was created in the slot region and its field intensity was 14× stronger than the evanescent sensing field from the TM polarization. The nanoscale confinement of the optical sensing field significantly enhanced the light-analyte interaction and improved the optical sensitivity. The sensitivity enhancement was experimentally demonstrated by measuring the polarization-dependent fluorescence emission from the tagged oligonucleotide. The photonic chips consisting of femtoliter Si3N4 waveguides provide a low-cost and high throughput platform for real-time virus identification, which is critical for point-of-care (PoC) diagnostic applications.


Asunto(s)
/métodos , /virología , ADN Viral/análisis , Nanopartículas/química , /aislamiento & purificación , Compuestos de Silicona/química , Humanos , Óptica y Fotónica , Sistemas de Atención de Punto , Refractometría , Semiconductores , Sensibilidad y Especificidad
5.
Arthroscopy ; 37(3): 901-902, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33673970

RESUMEN

Adult stem cells have been isolated in bone marrow and adipose tissue. These mesenchymal stromal cells (MSCs) have the ability to differentiate into osteogenic, chondrogenic, and adipogenic cell lines. The study by Branch et al. has identified MSCs in the synovial fluid of the knee in patients after anterior cruciate ligament injury and in patients with osteoarthritis of the knee. When mixing synovial fluid with whole blood and using a commercially available platelet-rich plasma-processing system, the total number of MSCs doubled in both groups when compared with the cell count in synovial fluid only. However, it is not clear whether the MSCs in the processed synovium-whole blood mix include synovial MSCs versus MSCs from only the blood. In addition, cell counts were substantially lower when compared with the typical concentrations of MSCs in bone marrow aspirate. The clinical application is yet to be defined.


Asunto(s)
Plasma Rico en Plaquetas , Líquido Sinovial , Tejido Adiposo , Adulto , Médula Ósea , Células de la Médula Ósea , Huesos , Diferenciación Celular , Condrogénesis , Humanos , Articulación de la Rodilla , Sistemas de Atención de Punto , Membrana Sinovial
6.
BMJ Case Rep ; 14(3)2021 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-33727298

RESUMEN

A 64-year-old man was intubated and ventilated for COVID-19-associated acute respiratory distress syndrome. He had a background history of chronic obstructive pulmonary disease and ischaemic heart disease. His oxygen saturations dropped rapidly to 80% on day 9 of ICU admission. Chest auscultation revealed absent breath sounds over the left upper chest which raised suspicions for pneumothorax, of which a small stable left apical pneumothorax was documented on a recent CT scan of the thorax. Point-of-care ultrasonography was performed prior to attempting chest drain insertion which demonstrated sliding pleura on the left side (GE Healthcare model: Vscan Extend-display: 5 inches, 720×1280 pixels resolution, sector probe-broad bandwidth: 1.7-3.8 MHz, 24 cm penetration and linear probe-broad bandwidth: 3.3-8 MHz, 8 cm penetration). A portable chest X-ray was obtained which demonstrated left upper lobe collapse secondary to mucus plugging. The mucus plug was successfully suctioned from the patient's airway using bedside bronchoscopy subsequently improving the patient's oxygen saturation. A follow-up chest X-ray and CT scan of the thorax demonstrated interval resolution of the left upper lobe collapse. While expansion of his existing pneumothorax was first on the list of differential diagnoses, the use of ultrasonography early in the patient's assessment ensured it was ruled out prior to attempting chest drain insertion, thus prompting the acquisition of the chest X-ray which subsequently demonstrated the left upper lobe collapse as the correct diagnosis.


Asunto(s)
/complicaciones , Cuidados Críticos/métodos , Sistemas de Atención de Punto , /etiología , Ultrasonografía/métodos , /sangre , Diagnóstico Diferencial , Humanos , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Oxígeno/sangre , /sangre
7.
Indian J Ophthalmol ; 69(4): 964-970, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33727467

RESUMEN

Purpose: The aim of this study was to report the use and the impact of a point-of-care rapid antigen test (PoC-RAT) at a tertiary eye care facility in facilitating commencement of elective surgeries, contact tracing of exposed health care professionals (HCPs) and ancillary hospital staff, and implementation of back-to-work (BTW) policy for them. Methods: Retrospective analysis of subjects undergoing PoC-RAT for COVID-19 infection at a tertiary level dedicated eye care facility. Decision making with regard to commencement of elective surgeries post COVID-19 related discontinuation of services, contact tracing of HCPs and ancillary hospital staff exposed to known COVID-19 cases and implementation of back-to-work policy for all staff based upon the results of PoC-RAT were studied. Results: A total of 311 subjects (224 patients and 87 hospital staff) were tested. Overall positivity rate was around 7%. Asymptomatic patients who were screened preoperatively had a lower positivity rate at around 3% compared to the staff (who were either known contacts or were symptomatic) at around 17%. Contact tracing found three-quarters of the staff at low risk and only one quarter at medium or high risk. Among patients, 97% of those followed up for at least 2 weeks after the test remained healthy. For staff, this was around 65%. Conclusion: Based on our preliminary results, we suggest that PoC-RAT may be considered routinely for indication-based preoperative screening of asymptomatic patients, and for on-campus screening, contact tracing and implementation of BTW policies for HCPs and ancillary hospital staff at a tertiary level eye care facility.


Asunto(s)
Antígenos Virales/inmunología , /diagnóstico , Trazado de Contacto , Procedimientos Quirúrgicos Electivos , Reinserción al Trabajo , /inmunología , Adulto , Toma de Decisiones , Femenino , Política de Salud , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Sistemas de Atención de Punto , Cuidados Preoperatorios , Estudios Retrospectivos , Centros de Atención Terciaria
8.
BMC Med Educ ; 21(1): 175, 2021 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-33743680

RESUMEN

BACKGROUND: Point-of-care ultrasound is becoming a ubiquitous diagnostic tool, and there has been increasing interest to teach novice practitioners. One of the challenges is the scarcity of qualified instructors, and with COVID-19, another challenge is the difficulty with social distancing between learners and educators. The purpose of our study was to determine if ultrasound-naïve operators can learn ultrasound techniques and develop the psychomotor skills to acquire ultrasound images after reviewing SonoSim® online modules. METHODS: This was a prospective study evaluating first-year medical students. Medical students were asked to complete four SonoSim® online modules (aorta/IVC, cardiac, renal, and superficial). They were subsequently asked to perform ultrasound examinations on standardized patients utilizing the learned techniques/skills in the online modules. Emergency Ultrasound-trained physicians evaluated medical students' sonographic skills in image acquisition quality, image acquisition difficulty, and overall performance. Data are presented as means and percentages with standard deviation. All P values are based on 2-tailed tests of significance. RESULTS: Total of 44 medical students participated in the study. All (100%) students completed the hands-on skills evaluation with a median score of 83.7% (IQR 76.7-88.4%). Thirty-three medical students completed all the online modules and quizzes with median score of 87.5% (IQR 83.8-91.3%). There was a positive association between module quiz performance and the hands-on skills performance (R-squared = 0.45; p < 0.001). There was no statistically significant association between module performance and hands-on performance for any of the four categories individually. In all four categories, the evaluators' observation of the medical students' difficulty obtaining views correlated with hands-on performance scores. CONCLUSIONS: Our study findings suggest that ultrasound-naïve medical students can develop basic hands-on skills in image acquisition after reviewing online modules.


Asunto(s)
Competencia Clínica , Educación a Distancia/métodos , Educación de Pregrado en Medicina/métodos , Sistemas de Atención de Punto , Ultrasonografía , /epidemiología , Femenino , Humanos , Masculino , Estudios Prospectivos
9.
Cochrane Database Syst Rev ; 3: CD013705, 2021 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-33760236

RESUMEN

BACKGROUND: Accurate rapid diagnostic tests for SARS-CoV-2 infection could contribute to clinical and public health strategies to manage the COVID-19 pandemic. Point-of-care antigen and molecular tests to detect current infection could increase access to testing and early confirmation of cases, and expediate clinical and public health management decisions that may reduce transmission. OBJECTIVES: To assess the diagnostic accuracy of point-of-care antigen and molecular-based tests for diagnosis of SARS-CoV-2 infection. We consider accuracy separately in symptomatic and asymptomatic population groups. SEARCH METHODS: Electronic searches of the Cochrane COVID-19 Study Register and the COVID-19 Living Evidence Database from the University of Bern (which includes daily updates from PubMed and Embase and preprints from medRxiv and bioRxiv) were undertaken on 30 Sept 2020. We checked repositories of COVID-19 publications and included independent evaluations from national reference laboratories, the Foundation for Innovative New Diagnostics and the Diagnostics Global Health website to 16 Nov 2020. We did not apply language restrictions. SELECTION CRITERIA: We included studies of people with either suspected SARS-CoV-2 infection, known SARS-CoV-2 infection or known absence of infection, or those who were being screened for infection. We included test accuracy studies of any design that evaluated commercially produced, rapid antigen or molecular tests suitable for a point-of-care setting (minimal equipment, sample preparation, and biosafety requirements, with results within two hours of sample collection). We included all reference standards that define the presence or absence of SARS-CoV-2 (including reverse transcription polymerase chain reaction (RT-PCR) tests and established diagnostic criteria). DATA COLLECTION AND ANALYSIS: Studies were screened independently in duplicate with disagreements resolved by discussion with a third author. Study characteristics were extracted by one author and checked by a second; extraction of study results and assessments of risk of bias and applicability (made using the QUADAS-2 tool) were undertaken independently in duplicate. We present sensitivity and specificity with 95% confidence intervals (CIs) for each test and pooled data using the bivariate model separately for antigen and molecular-based tests. We tabulated results by test manufacturer and compliance with manufacturer instructions for use and according to symptom status. MAIN RESULTS: Seventy-eight study cohorts were included (described in 64 study reports, including 20 pre-prints), reporting results for 24,087 samples (7,415 with confirmed SARS-CoV-2). Studies were mainly from Europe (n = 39) or North America (n = 20), and evaluated 16 antigen and five molecular assays. We considered risk of bias to be high in 29 (50%) studies because of participant selection; in 66 (85%) because of weaknesses in the reference standard for absence of infection; and in 29 (45%) for participant flow and timing. Studies of antigen tests were of a higher methodological quality compared to studies of molecular tests, particularly regarding the risk of bias for participant selection and the index test. Characteristics of participants in 35 (45%) studies differed from those in whom the test was intended to be used and the delivery of the index test in 39 (50%) studies differed from the way in which the test was intended to be used. Nearly all studies (97%) defined the presence or absence of SARS-CoV-2 based on a single RT-PCR result, and none included participants meeting case definitions for probable COVID-19. Antigen tests Forty-eight studies reported 58 evaluations of antigen tests. Estimates of sensitivity varied considerably between studies. There were differences between symptomatic (72.0%, 95% CI 63.7% to 79.0%; 37 evaluations; 15530 samples, 4410 cases) and asymptomatic participants (58.1%, 95% CI 40.2% to 74.1%; 12 evaluations; 1581 samples, 295 cases). Average sensitivity was higher in the first week after symptom onset (78.3%, 95% CI 71.1% to 84.1%; 26 evaluations; 5769 samples, 2320 cases) than in the second week of symptoms (51.0%, 95% CI 40.8% to 61.0%; 22 evaluations; 935 samples, 692 cases). Sensitivity was high in those with cycle threshold (Ct) values on PCR ≤25 (94.5%, 95% CI 91.0% to 96.7%; 36 evaluations; 2613 cases) compared to those with Ct values >25 (40.7%, 95% CI 31.8% to 50.3%; 36 evaluations; 2632 cases). Sensitivity varied between brands. Using data from instructions for use (IFU) compliant evaluations in symptomatic participants, summary sensitivities ranged from 34.1% (95% CI 29.7% to 38.8%; Coris Bioconcept) to 88.1% (95% CI 84.2% to 91.1%; SD Biosensor STANDARD Q). Average specificities were high in symptomatic and asymptomatic participants, and for most brands (overall summary specificity 99.6%, 95% CI 99.0% to 99.8%). At 5% prevalence using data for the most sensitive assays in symptomatic people (SD Biosensor STANDARD Q and Abbott Panbio), positive predictive values (PPVs) of 84% to 90% mean that between 1 in 10 and 1 in 6 positive results will be a false positive, and between 1 in 4 and 1 in 8 cases will be missed. At 0.5% prevalence applying the same tests in asymptomatic people would result in PPVs of 11% to 28% meaning that between 7 in 10 and 9 in 10 positive results will be false positives, and between 1 in 2 and 1 in 3 cases will be missed. No studies assessed the accuracy of repeated lateral flow testing or self-testing. Rapid molecular assays Thirty studies reported 33 evaluations of five different rapid molecular tests. Sensitivities varied according to test brand. Most of the data relate to the ID NOW and Xpert Xpress assays. Using data from evaluations following the manufacturer's instructions for use, the average sensitivity of ID NOW was 73.0% (95% CI 66.8% to 78.4%) and average specificity 99.7% (95% CI 98.7% to 99.9%; 4 evaluations; 812 samples, 222 cases). For Xpert Xpress, the average sensitivity was 100% (95% CI 88.1% to 100%) and average specificity 97.2% (95% CI 89.4% to 99.3%; 2 evaluations; 100 samples, 29 cases). Insufficient data were available to investigate the effect of symptom status or time after symptom onset. AUTHORS' CONCLUSIONS: Antigen tests vary in sensitivity. In people with signs and symptoms of COVID-19, sensitivities are highest in the first week of illness when viral loads are higher. The assays shown to meet appropriate criteria, such as WHO's priority target product profiles for COVID-19 diagnostics ('acceptable' sensitivity ≥ 80% and specificity ≥ 97%), can be considered as a replacement for laboratory-based RT-PCR when immediate decisions about patient care must be made, or where RT-PCR cannot be delivered in a timely manner. Positive predictive values suggest that confirmatory testing of those with positive results may be considered in low prevalence settings. Due to the variable sensitivity of antigen tests, people who test negative may still be infected. Evidence for testing in asymptomatic cohorts was limited. Test accuracy studies cannot adequately assess the ability of antigen tests to differentiate those who are infectious and require isolation from those who pose no risk, as there is no reference standard for infectiousness. A small number of molecular tests showed high accuracy and may be suitable alternatives to RT-PCR. However, further evaluations of the tests in settings as they are intended to be used are required to fully establish performance in practice. Several important studies in asymptomatic individuals have been reported since the close of our search and will be incorporated at the next update of this review. Comparative studies of antigen tests in their intended use settings and according to test operator (including self-testing) are required.


Asunto(s)
Antígenos Virales/análisis , /diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Sistemas de Atención de Punto , /inmunología , Adulto , Infecciones Asintomáticas , Sesgo , Niño , Estudios de Cohortes , Reacciones Falso Negativas , Reacciones Falso Positivas , Humanos , Técnicas de Diagnóstico Molecular/normas , Valor Predictivo de las Pruebas , Estándares de Referencia , Sensibilidad y Especificidad
10.
J Infect Dev Ctries ; 15(2): 237-241, 2021 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-33690206

RESUMEN

INTRODUCTION: We aim to describe the performance of combined IgM and IgG point-of-care antibody test (POC-Ab) (Wondfo®) compared to real-time reverse transcriptase (rRT-PCR) (Allplex™ 2019-nCoV Assay) in detecting coronavirus disease 2019 (COVID-19). METHODOLOGY: We compared POC-Ab with rRT-PCR results among patients in a tertiary hospital from January to March 2020 in Bandung, Indonesia. We selected presumptive COVID-19 patients with positive rRT-PCR consecutively and 20 patients with negative rRT-PCR results were selected randomly from the same group of patients as controls. We described the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) with corresponding 95% confidence interval using serum and capillary blood samples. We also tested POC-Ab using non-COVID-19 (confirmed dengue and typhoid) patients' sera. RESULTS: Twenty-seven patients with positive rRT-PCR result and 20 negative controls were included (68.1% males, mean age 46 (SD: 15.4)). Using the serum, the sensitivity of the POC-Ab was 63.0% (42.4-80.6), specificity was 95.0% (75.1-99.9), PPV was 94.4% (72.7-99.8), NPV was 65.5% (45.7-82.1). A subset of 20 patients was tested using a capillary blood sample. The accuracy of the capillary blood sample is lower compared to serum (50.0% vs. 78.7%). None of the non-COVID-19 sera tested were reactive. CONCLUSIONS: POC-Ab for COVID-19 has a high specificity with no false-positive result in non-COVID-19 sera. Therefore, it can be used to guide diagnostic among symptomatic patients in resource limited settings. Given its low sensitivity, patients with high suspicion of COVID-19 but non-reactive result should be prioritized for rRT-PCR testing.


Asunto(s)
/métodos , Adulto , Anciano , /etiología , Reacciones Falso Positivas , Femenino , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Indonesia , Masculino , Persona de Mediana Edad , Nasofaringe/virología , Sistemas de Atención de Punto , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Sensibilidad y Especificidad , Centros de Atención Terciaria
11.
Arch Pathol Lab Med ; 145(3): 308-319, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33635952

RESUMEN

CONTEXT.­: Point-of-care test (POCT) instruments produce lab results with rapid turnaround times. Based on that fact, emergency department (ED) POCT requests are predicated on the belief that rapid test turnaround times lead to improved care, typically a decreased ED length of stay (LOS). OBJECTIVE.­: To compile the available peer-reviewed data regarding use of POCT in the ED with an emphasis on ED-LOS. DATA SOURCES.­: An English-language PubMed search using the following free text terms: ("EMERGENCY" AND "POINT OF CARE") NOT ULTRASOUND as well as "RAPID INFECTIOUS DISEASE TESTING." In addition, the PubMed "similar articles" functionality was used to identify related articles that were not identified on the initial search. CONCLUSIONS.­: Seventy-four references were identified that studied POCT ED use to determine if they resulted in significant changes in ED processes, especially ED-LOS. They were divided into 3 groups: viral-influenza (n = 24), viral-respiratory not otherwise specified (n = 8), and nonviral (n = 42). The nonviral group was further divided into the following groups: chemistry, cardiac, bacterial/strep, C-reactive protein, D-dimer, drugs of abuse, lactate, and pregnancy. Across all groups there was a trend toward a significantly decreased ED-LOS; however, a number of studies showed no change, and a third group was not assessed for ED-LOS. For POCT to improve ED-LOS it has to be integrated into existing ED processes such that a rapid test result will allow the patient to have a shorter LOS, whether it is to discharge or admission.


Asunto(s)
Servicio de Urgencia en Hospital/normas , Pruebas en el Punto de Atención/normas , Humanos , Tiempo de Internación , Sistemas de Atención de Punto , Factores de Tiempo
12.
Biosens Bioelectron ; 178: 113049, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33540323

RESUMEN

Prompt diagnosis, patient isolation, and contact tracing are key measures to contain the coronavirus disease 2019 (COVID-19). Molecular tests are the current gold standard for COVID-19 detection, but are carried out at central laboratories, delaying treatment and control decisions. Here we describe a portable assay system for rapid, onsite COVID-19 diagnosis. Termed CODA (CRISPR Optical Detection of Anisotropy), the method combined isothermal nucleic acid amplification, activation of CRISPR/Cas12a, and signal generation in a single assay, eliminating extra manual steps. Importantly, signal detection was based on the ratiometric measurement of fluorescent anisotropy, which allowed CODA to achieve a high signal-to-noise ratio. For point-of-care operation, we built a compact, standalone CODA device integrating optoelectronics, an embedded heater, and a microcontroller for data processing. The developed system completed SARS-CoV-2 RNA detection within 20 min of sample loading; the limit of detection reached 3 copy/µL. When applied to clinical samples (10 confirmed COVID-19 patients; 10 controls), the rapid CODA test accurately classified COVID-19 status, in concordance with gold-standard clinical diagnostics.


Asunto(s)
Técnicas Biosensibles/métodos , /diagnóstico , Polarización de Fluorescencia/métodos , /aislamiento & purificación , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/estadística & datos numéricos , /instrumentación , Sistemas CRISPR-Cas , Diseño de Equipo , Polarización de Fluorescencia/instrumentación , Polarización de Fluorescencia/estadística & datos numéricos , Humanos , Técnicas de Diagnóstico Molecular/instrumentación , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/estadística & datos numéricos , Técnicas de Amplificación de Ácido Nucleico/instrumentación , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas de Amplificación de Ácido Nucleico/estadística & datos numéricos , Pandemias , Sistemas de Atención de Punto/estadística & datos numéricos , Procesamiento de Señales Asistido por Computador , Relación Señal-Ruido
13.
Biosens Bioelectron ; 178: 113041, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33545551

RESUMEN

The outbreak of COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been challenging human health worldwide. Loop-mediated isothermal amplification (LAMP) has been promptly applied to the detection of SARS-CoV-2 owing to its high amplification efficacy and less requirement of the thermal cycler. However, the vast majority of these LAMP-based assays depend on the non-specific detection of LAMP products, which can not discern the undesirable amplificons, likely to yield unreliable results. Herein, a sequence-specific LAMP assay was reported to detect SARS-CoV-2 using proofreading enzyme-mediated probe cleavage (named Proofman), which could realize real-time and visual detection without uncapping. This assay, introducing a proofreading enzyme and the fluorogenic probe to reverse-transcription LAMP (RT-Proofman-LAMP), can specifically detect the SARS-CoV-2 RNA with a detection limit of 100 copies. In addition to the real-time analysis, the assay is capable of endpoint visualization under a transilluminator within 50 min, providing a convenient reporting manner under the setting of point-of-care testing (POCT). In combination with different fluorophores, the one-pot multiplex assay was successfully achieved to detect multiple targets of SARS-CoV-2 and inner control simultaneously. In summary, the development of RT-Proofman-LAMP offers a versatile and highly-specific method for fast field screening and laboratory testing of SARS-CoV-2, making it a promising platform in COVID-19 diagnosis.


Asunto(s)
/métodos , /virología , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , /aislamiento & purificación , Técnicas Biosensibles/métodos , Técnicas Biosensibles/estadística & datos numéricos , Humanos , Límite de Detección , Técnicas de Diagnóstico Molecular/estadística & datos numéricos , Reacción en Cadena de la Polimerasa Multiplex/métodos , Reacción en Cadena de la Polimerasa Multiplex/estadística & datos numéricos , Técnicas de Amplificación de Ácido Nucleico/estadística & datos numéricos , Pandemias , Sistemas de Atención de Punto/estadística & datos numéricos , ARN Viral/análisis , ARN Viral/genética , Sensibilidad y Especificidad
14.
ASAIO J ; 67(3): 254-262, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33627598

RESUMEN

Viscoelastic coagulation monitor (VCM) is a portable device developed to evaluate the viscoelastic properties of whole blood activated by contact with glass. In this study, VCM was employed to analyze the viscoelastic profiles of 36 COVID-19 intensive care patients. Full anticoagulant dose heparin (unfractionated [UFH]; low molecular weight [LMWH]) was administrated to all patients. The association between VCM and laboratory parameters was retrospectively analyzed. The administration of UFH-influenced VCM parameters prolonging clotting time (CT) and clot formation time (CFT) and reducing angle (alpha) and amplitudes of the VCM tracings (A10, A20, and maximum clot firmness [MCF]) compared with LMWH therapy. A tendency toward hypercoagulation was observed by short CT and CFT in patients receiving LMWH. Clotting time was correlated with UFH dose (Spearman's rho = 0.48, p ≤ 0.001), and no correlation was found between CT and LMWH. All VCM tracings failed to show lysis at 30 and 45 minutes, indicating the absence of fibrinolysis. A10, A20, and MCF exhibited very-good to good diagnostic accuracy for detecting platelet count and fibrinogen above the upper reference limit of the laboratory. In conclusion, VCM provided reliable results in COVID-19 patients and was easy to perform with minimal training at the bedside.


Asunto(s)
/sangre , Monitoreo Fisiológico/instrumentación , Sistemas de Atención de Punto , Tromboelastografía/instrumentación , Adulto , Coagulación Sanguínea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico/métodos , Estudios Retrospectivos , Tromboelastografía/métodos , Trombosis/diagnóstico , Trombosis/virología
15.
PLoS One ; 16(2): e0245914, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33596236

RESUMEN

In the emergency of the SARS-CoV-2 pandemic, great efforts were made to quickly provide serology testing to the medical community however, these methods have been introduced into clinical practice without the complete validation usually required by the regulatory organizations. SARS-CoV-2 patient samples (n = 43) were analyzed alongside pre-pandemic control specimen (n = 50), confirmed respiratory infections (n = 50), inflammatory polyarthritis (n = 22) and positive for thyroid stimulating immunoglobulin (n = 30). Imprecision, diagnostic sensitivity and specificity and concordance were evaluated on IgG serologic assays from EuroImmun, Epitope Diagnostics (EDI), Abbott Diagnostics and DiaSorin and a rapid IgG/IgM test from Healgen. EDI and EuroImmun imprecision was 0.02-14.0% CV. Abbott and DiaSorin imprecision (CV) ranged from 5.2%-8.1% and 8.2%-9.6% respectively. Diagnostic sensitivity of the assays was 100% (CI: 80-100%) for Abbott, EDI and EuroImmun and 95% (CI: 73-100%) for DiaSorin at ≥14 days post PCR. Only the Abbott assay had a diagnostic specificity of 100% (CI: 91-100%). EuroImmun cross-reacted in 3 non-SARS-CoV-2 respiratory infections and 2 controls. The DiaSorin displayed more false negative results and cross-reacted in six cases across all conditions tested. EDI had one cross-reactive sample. The Healgen rapid test showed excellent sensitivity and specificity. Overall, concordance of the assays ranged from 76.1% to 97.9%. Serological tests for SARS-CoV-2 showed good analytical performance. The head-to-head analysis of samples revealed differences in results that may be linked to the use of nucleocapsid or spike proteins. The point of care device tested demonstrated adequate performance for antibody detection.


Asunto(s)
/métodos , /inmunología , Anticuerpos Antivirales/sangre , Brasil/epidemiología , /inmunología , /tendencias , Técnicas de Laboratorio Clínico/métodos , Reacciones Cruzadas , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Pandemias , Sistemas de Atención de Punto , Sensibilidad y Especificidad
16.
ACS Appl Mater Interfaces ; 13(7): 8042-8048, 2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33576594

RESUMEN

Biomarkers based on DNA methylation have attracted wide attention in biomedical research due to their potential clinical value. Therefore, a sensitive and accurate method for DNA methylation detection is highly desirable for the discovery and diagnostics of human diseases, especially cancers. Here, an integrated, low-cost, and portable point-of-care (POC) device is presented to analyze DNA methylation, which integrates the process of pyrosequencing in a digital microfluidic chip. Without additional equipment and complicated operation, droplets are manipulated by patterned electrodes with individually programmed control. The system exhibited an excellent sensitivity with a limit of detection (LOD) of 10 pg and a comparable checkout down to 5% methylation level within 30 min, which offered a potential substitute for the detection of DNA methylation. With the advantages of portability, ease of use, high accuracy, and low cost, the POC platform shows great potential for the analysis of tumor-specific circulating DNA.


Asunto(s)
Automatización , ADN/análisis , Dispositivos Laboratorio en un Chip , Técnicas Analíticas Microfluídicas , Sistemas de Atención de Punto , Biomarcadores/análisis , ADN/genética , Metilación de ADN , Humanos , Técnicas Analíticas Microfluídicas/instrumentación
17.
Clin Lab ; 67(2)2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33616334

RESUMEN

BACKGROUND: COVID-19 has recently been declared an epidemic by the WHO, and there is an urgent need for affected countries and laboratories to assess and treat people at risk of COVID-19. A heat procedure has been suggested for specimen inactivation. This study was designed to evaluate the effect of serum heating on biochemical indexes, and providing a basis for accurate detection results of the COVID-19 patients. METHODS: We collected 29 normal cases of two tubes of 5 mL whole blood. One tube was analyzed directly, and the other was analyzed after heating at 56°C 30 minutes. RESULTS: A total of 34 serum biochemical index quantitative results were obtained, 28/34 indexes were not significantly affected by the heat inactivation and remained clinically interpretable. As the thermal inactivation for these indexes showed good correlation, ALB (p = 0.04, Pearson R = 0.91, 2.6% mean increase), CysC (p = 0.03, Pearson R = 0.98, 9.9% mean increase), CO2CP (p < 0.001, Pearson R = 0.96, 13% mean decrease), they were still inter-pretable. Four biochemical indexes ALP, CK, CK-MB, and insulin were inactivated and showed significant statistical differences (p < 0.001). CONCLUSIONS: Our study showed CK, CK-MB, ALP, and insulin were sensitive to heat and will be inhibited or degrade after heating, indicating that the rapid decrease of this indexes in the COVID-19 patients may be caused by sample heat inactivation. For safety and diagnostic accuracy, we recommend the use of a point-of-care device for blood gases, electrolytes, troponin, and liver and renal function tests within a ISL 2 or above biosafety cabinet with level 3 or above biosafety laboratory practice.


Asunto(s)
Análisis Químico de la Sangre , Errores Diagnósticos/prevención & control , Calor/efectos adversos , Inactivación de Virus , Fosfatasa Alcalina/sangre , Análisis Químico de la Sangre/métodos , Análisis Químico de la Sangre/normas , /diagnóstico , Creatina Quinasa/sangre , Femenino , Humanos , Insulina/sangre , Masculino , Persona de Mediana Edad , Sistemas de Atención de Punto , /fisiología , Sensibilidad y Especificidad
18.
BMJ Open ; 11(2): e041118, 2021 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-33568367

RESUMEN

INTRODUCTION: In the context of the COVID-19 pandemic, early identification of patients who are likely to get worse is a major concern. Severity mainly depends on the development of acute respiratory distress syndrome (ARDS) with a predominance of subpleural lesions. Lung point-of-care ultrasonography (L-POCUS) is highly effective in detecting pulmonary peripheral patterns and may be appropriate for examining patients with COVID-19. We suggest that L-POCUS performed during the initial examination may identify patients with COVID-19 who are at a high risk of complicated treatment or unfavourable evolution. METHODS AND ANALYSIS: Point-of-care ultrasonography for risk stratification of non-critical COVID-19 patients on admission is a prospective, multicentre study. Adult patients visiting the emergency department (ED) of participating centres for suspected or confirmed COVID-19 are assessed for inclusion. Included patients have L-POCUS performed within 48 hours following ED admission. The severity of lung damage is assessed using the L-POCUS score based on 36 points for ARDS. Apart from the L-POCUS score assessment, patients are treated as recommended by the WHO. For hospitalised patients, a second L-POCUS is performed at day 5±3. A follow-up is carried out on day 14, and the patient's status according to the Ordinal Scale for Clinical Improvement for COVID-19 from the WHO is recorded.The primary outcome is the rate of patients requiring intubation or who are dead from any cause during the 14 days following inclusion. We will determine the area under the ROC curve of L-POCUS. ETHICS AND DISSEMINATION: The protocol has been approved by the French and Belgian Ethics Committees and is carried out in accordance with the Declaration of Helsinki and Good Clinical Practice guidelines. The study is funding by a grant from the French Health Ministry, and its findings will be disseminated in peer-reviewed journals and at scientific conferences. TRIAL REGISTRATION NUMBER: NCT04338100.


Asunto(s)
/diagnóstico , Sistemas de Atención de Punto , Medición de Riesgo , Ultrasonografía , Adolescente , Servicio de Urgencia en Hospital , Humanos , Estudios Multicéntricos como Asunto , Pandemias , Admisión del Paciente , Estudios Prospectivos
19.
Medicine (Baltimore) ; 100(5): e24644, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33592916

RESUMEN

ABSTRACT: Point-of-care ultrasonography (POCUS) is a prompt and simple tool for the urgent diagnosis and treatment of patients in the emergency department (ED). We developed a comprehensive residency-based POCUS training program for ED residents and determined its effect on ultrasound utilization in the ED.We conducted a retrospective cohort study in the ED of a university-affiliated medical center, to evaluate a centralized residency-based POCUS training course for ED residents, which included 12 core ultrasound applications, from July 2017 to June 2018. Each application comprised a combined lecture and hands-on practice session that lasted for 2 hours. Pre-tests and post-tests, including still image and video interpretation, were performed. The use of POCUS (number of ultrasound studies performed divided by the number of patients each resident saw in 1 year) among ED residents, before and after the POCUS training course (July 2016-June 2017 and July 2018-June 2019), was calculated and analyzed using the Wilcoxon signed-rank test.Sixteen residents participated and completed the entire training course. The post-test score was significantly better than the pre-test score, by a median of 12 points (P = .04). Utilization of POCUS among the ED residents increased significantly, from 0.15 ultrasound studies per patient per year to 0.41 ultrasound studies per patient per year (P < .01), after completion of the entire training course. Increased POCUS scanning percentages over the cardiac tissue, soft tissue, abdominal region, vascular system, procedural guidance, and ocular regions were also noted after providing the curriculum.Conducting a comprehensive POCUS education program may enhance POCUS utilization among residents in the ED.


Asunto(s)
Medicina de Emergencia/educación , Servicio de Urgencia en Hospital/estadística & datos numéricos , Internado y Residencia/organización & administración , Sistemas de Atención de Punto , Ultrasonografía , Competencia Clínica , Hospitales Universitarios , Humanos , Estudios Retrospectivos , Taiwán
20.
J Intensive Care Med ; 36(3): 334-342, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33535883

RESUMEN

BACKGROUND: The prognostic value of point-of-care lung ultrasound has not been evaluated in a large cohort of patients with COVID-19 admitted to general medicine ward in the United States. The aim of this study was to describe lung ultrasound findings and their prognostic value in patients with COVID-19 admitted to internal medicine ward. METHOD: This prospective observational study consecutively enrolled 105 hospitalized participants with COVID-19 at 2 tertiary care centers. Ultrasound was performed in 12 lung zones within 24 hours of admission. Findings were assessed relative to 4 outcomes: intensive care unit (ICU) need, need for intensive respiratory support, length of stay, and death. RESULTS: We detected abnormalities in 92% (97/105) of participants. The common findings were confluent B-lines (92%), non-homogenous pleural lines (78%), and consolidations (54%). Large confluent B-lines, consolidations, bilateral involvement, and any abnormality in ≥ 6 areas were associated with a longer hospitalization and need for intensive respiratory support. Large confluent B-lines and bilateral involvement were also associated with ICU stay. A total lung ultrasound score <5 had a negative predictive value of 100% for the need of intensive respiratory support. A higher total lung ultrasound score was associated with ICU need (median total 18 in the ICU group vs. 11 non-ICU, p = 0.004), a hospitalization ≥ 9d (15 vs 10, p = 0.016) and need for intensive respiratory support (18 vs. 8.5, P < 0.001). CONCLUSIONS: Most patients hospitalized with COVID-19 had lung ultrasound abnormalities on admission and a higher lung ultrasound score was associated with worse clinical outcomes except death. A low total lung ultrasound score (<5) had a negative predictive value of 100% for the need of intensive respiratory support. Point-of-care ultrasound can aid in the risk stratification for patients with COVID-19 admitted to general wards.


Asunto(s)
/diagnóstico por imagen , Mortalidad Hospitalaria , Unidades de Cuidados Intensivos/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Pulmón/diagnóstico por imagen , Respiración Artificial/estadística & datos numéricos , Anciano , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Ventilación no Invasiva/estadística & datos numéricos , Sistemas de Atención de Punto , Pronóstico , Estudios Prospectivos , Ultrasonografía
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