High Clinical Performance Research Articles

A-021 Evaluation of a Novel N Terminal Pro B Type Natriuretic Peptide Assay as an aid in the Diagnosis of Acute Heart Failure in the Emergency Department

Abstract Background The signs and symptoms of acute heart failure (AHF) may overlap with other conditions and lead to diagnostic difficulty in the undifferentiated patient with dyspnea. The particularly high negative predictive value (NPV) of natriuretic peptides (NPs) in excluding AHF have rendered these assays especially useful in evaluating dyspnea in acute care setting. This study was conducted to assess the diagnostic performance of a novel N-terminal pro-B type natriuretic peptide (NT-proBNP) assay in the intended use patient population in the emergency department (ED). Methods A multicenter study was conducted in the U.S. on individuals presenting to the ED with dyspnea and a suspicion of AHF. Blood specimens were collected and tested using the Beckman Coulter Access NT-proBNP assay on the DxI 9000 Immunoassay Analyzer. Test results were compared to an adjudicated diagnosis clinical endpoint performed by an independent Clinical Events Committee blinded to the Access NT-proBNP result. Performance included NPV and sensitivity of an age-independent cut point of <300 ng/L to exclude AHF, and the positive predictive value (PPV) of the age-dependent cut points of >450, >900, and >1800 ng/L for ages <50 years, 50-75 years, and >75 years, respectively, for the diagnosis of AHF. The sample size required to achieve a 95% two tailed confidence interval (CI) was 150 subjects per age group to provide clinical performance at 90% (±10%) sensitivity. Sample size was based upon CLSI EP24-A2, Assessment of the Diagnostic Accuracy of Laboratory Tests Using Receiver Operating Characteristic Curves. Sensitivity and specificity were calculated at a series of cutoff points and plotted in separate receiver operation curves (ROC) for an overall age-independent rule-out analysis and for individual age-dependent groups separately. Area under the receiver operator characteristic curve (AUROC) was reported with 95% 2-sided CI. NPV and PPV with respective 95% 2-sided score CI was computed for the overall age-independent cut point and for each age group cohort. Results Of 490 enrolled patients, 41% were adjudicated with AHF with a median (Q1, Q3) age of 60 (47-76) years, and distributions of 46.1% female, 60.8% White and 38.2% Black. The assay had an AUROC for AHF of 0.88 (P<0.001), comparable to other commercially available NT-proBNP assays. The rule-out cut point of <300 ng/L had 96% sensitivity and NPV of 95%. Age-dependent cut points had sensitivity of 84%, 90%, and 87%, specificity of 81%, 70% and 61%, and PPV of 72%, 62%, and 74%, respectively. Conclusions The Access NT-proBNP assay demonstrated high clinical performance in the diagnosis and exclusion of acute HF in the undifferentiated dyspneic patient population and performed similarly well to validated assays used in current clinical practice. Given the continued increase in importance and reach of natriuretic peptide testing, these results are useful to extend availability of this assay to a larger audience.

High failure rate but promising clinical performance after implantation of a flexible medial meniscus prosthesis at 1-year follow-up.

After unsatisfactory results in a first-in-human clinical investigation with an anatomically shaped medial meniscus prosthesis, the prosthesis and its fixation technique were altered. This interim analysis of a prospective single-arm clinical investigation aims to evaluate safety and clinical performance in a first-in-human study with the redesigned meniscus prosthesis system. Ten patients suffering from medial postmeniscectomy pain syndrome were treated with the meniscus prosthesis. Patient-reported outcome measures were obtained at baseline and at 6-week, 3-, 6-, and 12-month follow-up. Radiographs and magnetic resonance imaging scans were obtained to evaluate joint degeneration and prosthesis location. The device alterations resolved the issues occurring with the previous design, but four prostheses were explanted after fixation failure or subluxation of the prosthesis. Five out of six patients who reached 1-year follow-up reported a clinically significant improvement of the knee injury and osteoarthritis outcome score pain subscale. Imaging revealed no adverse effects on joint degeneration. The failure mechanisms that occurred with the previous design have been resolved, but the new fixation technique introduced new safety issues. Improvement of positioning and fixation techniques are considered essential future adaptations to reduce the risk of failure. The good clinical outcomes reported by the patients reaching 1-year follow-up indicate that the medial meniscus prosthesis is a potential solution for patients suffering from postmeniscectomy pain syndrome. Level II.

Interlaboratory Harmonization Study and Prospective Evaluation of the PURE–Trypanosoma cruzi–Loop-Mediated Isothermal Amplification Assay for Detecting Parasite DNA in Newborn's Dried Blood Spots

Timely diagnosis of vertical Trypanosoma cruzi infections involves microscopy-based detection of circulating parasites from peripheral blood, which lacks sensitivity and is operator dependent. Consequently, most children born to T. cruzi-infected mothers are required to undergo serological testing after nine months, which risks loss to follow-up. Alternatively, the Loop-mediated isothermal amplification (LAMP) test for T. cruzi DNA offers high analytical and clinical performance and easy to use in low-complexity laboratories. Recently, we optimized this technique using an ultra-rapid DNA extraction method combined with the LAMP in dried blood spots (DBS) on FTA cards. The procedure has been implemented in ten public maternities across Paraguay, Bolivia, and Argentina, involving the training of 14 technicians. Operators' performance was evaluated using a standardized DBS testing panel for harmonization, including negative controls and DBS samples artificially contaminated with T. cruzi at 50 and 20 cells/mL. There was strong agreement (ĸ = 0.924) for controls and 50 cells/mL samples, and good agreement (ĸ = 0.718) across all testing panels, even at the detection limit of the test. A prospective study collected 306 DBS from 222 newborns at birth and/or two months, detecting T. cruzi microscopically in four cases. LAMP identified eight positive cases and perfectly aligned with Real Time PCR (ĸ = 1), demonstrating higher sensitivity than microscopic observation for early detection of infection in infants.

Machine learning model for non-alcoholic steatohepatitis diagnosis based on ultrasound radiomics

BackgroundNon-Alcoholic Steatohepatitis (NASH) is a crucial stage in the progression of Non-Alcoholic Fatty Liver Disease(NAFLD). The purpose of this study is to explore the clinical value of ultrasound features and radiological analysis in predicting the diagnosis of Non-Alcoholic Steatohepatitis.MethodAn SD rat model of hepatic steatosis was established through a high-fat diet and subcutaneous injection of CCl4. Liver ultrasound images and elastography were acquired, along with serum data and histopathological results of rat livers.The Pyradiomics software was used to extract radiomic features from 2D ultrasound images of rat livers. The rats were then randomly divided into a training set and a validation set, and feature selection was performed through dimensionality reduction. Various machine learning (ML) algorithms were employed to build clinical diagnostic models, radiomic models, and combined diagnostic models. The efficiency of each diagnostic model for diagnosing NASH was evaluated using Receiver Operating Characteristic (ROC) curves, Clinical Decision Curve Analysis (DCA), and calibration curves.ResultsIn the machine learning radiomic model for predicting the diagnosis of NASH, the Area Under the Curve (AUC) of ROC curve for the clinical radiomic model in the training set and validation set were 0.989 and 0.885, respectively. The Decision Curve Analysis revealed that the clinical radiomic model had the highest net benefit within the probability threshold range of > 65%. The calibration curve in the validation set demonstrated that the clinical combined radiomic model is the optimal method for diagnosing Non-Alcoholic Steatohepatitis.ConclusionThe combined diagnostic model constructed using machine learning algorithms based on ultrasound image radiomics has a high clinical predictive performance in diagnosing Non-Alcoholic Steatohepatitis.

Evaluating Retention of Onlay Versus Complete Coverage Using E.Max-Restoration

This study compared the retention of different types of indirect restorations (only or full coverage) utilized on endodontically treated molars. Fourteen patients requiring restoration of endodontically treated molars were randomly allocated into two groups (n = 7) according to the type of restoration used. lithium disilicate ceramic crowns were given to the control group. While lithium disilicate ceramic onlays were given to the intervention group. The heat pressing technique was used for the fabrication of both restorations. Following the final cementation with adhesive resin cement, the restoration was assessed at three, six, twelve, and twenty-four months using the modified USPHS criteria. Statistical analysis was performed using the chi-square test. Results: At all intervals, there was no statistically significant difference in retention (P > 0.05) between the two tested groups. Both groups showed comparable results, with full coverage showing somewhat higher retention after 2 years. Regardless of the type of restoration, the emax-press produced high clinical performance in terms of retention. Compared to full coverage, onlay has proven to be a trustworthy substitute.

Reliability, clinical performance and trending ability of a pulse oximeter and pulse co-oximeter, in monitoring blood oxygenation, at two measurement sites, in immobilised white rhinoceros (Ceratotherium simum)

BackgroundMonitoring blood oxygenation is essential in immobilised rhinoceros, which are susceptible to opioid-induced hypoxaemia. This study assessed the reliability, clinical performance and trending ability of the Nonin PalmSAT 2500 A pulse oximeter’s and the Masimo Radical-7 pulse co-oximeter’s dual-wavelength technology, with their probes placed at two measurement sites, the inner surface of the third-eyelid and the scarified ear pinna of immobilised white rhinoceroses. Eight white rhinoceros were immobilised with etorphine-based drug combinations and given butorphanol after 12 min, and oxygen after 40 min, of recumbency. The Nonin and Masimo devices, with dual-wavelength probes attached to the third-eyelid and ear recorded arterial peripheral oxygen-haemoglobin saturation (SpO2) at pre-determined time points, concurrently with measurements of arterial oxygen-haemoglobin saturation (SaO2), from drawn blood samples, by a benchtop AVOXimeter 4000 co-oximeter (reference method). Reliability of the Nonin and Masimo devices was evaluated using the Bland-Altman and the area root mean squares (ARMS) methods. Clinical performance of the devices was evaluated for their ability to accurately detect clinical hypoxemia using receiver operating characteristic (ROC) curves and measures of sensitivity, specificity, and positive and negative predictive values. Trending ability of the devices was assessed by calculating concordance rates from four-quadrant plots.ResultsOnly the Nonin device with transflectance probe attached to the third-eyelid provided reliable SpO2 measurements across the 70 to 100% saturation range (bias − 1%, precision 4%, ARMS 4%). Nonin and Masimo devices with transflectance probes attached to the third-eyelid both had high clinical performance at detecting clinical hypoxaemia [area under the ROC curves (AUC): 0.93 and 0.90, respectively]. However, the Nonin and Masimo devices with transmission probes attached to the ear were unreliable and provided only moderate clinical performance. Both Nonin and Masimo devices, at both measurement sites, had concordance rates lower than the recommended threshold of ≥ 90%, indicating poor trending ability.ConclusionsThe overall assessment of reliability, clinical performance and trending ability indicate that the Nonin device with transflectance probe attached to the third-eyelid is best suited for monitoring of blood oxygenation in immobilised rhinoceros. The immobilisation procedure may have affected cardiovascular function to an extent that it limited the devices’ performance.

Two-year clinical and radiographic evaluation of ACTIVA BioACTIVE versus Compomer (Dyract® eXtra) in the restoration of class-2 cavities of primary molars: a non-inferior split-mouth randomised clinical trial

ObjectivesThe trial aimed to compare the clinical performance and radiographic success of ACTIVA BioACTIVE versus Compomer in restoring class-II cavities of primary molars.Materials and methodsA non-inferior split-mouth design was considered. A pre-calculated sample size of 96 molars (48 per group) with class-2 cavities of twenty-one children whose ages ranged from 5 to 10 years were randomly included in the trial. Pre-operative Plaque Index (PI), DMFT/dmft scores and the time required to fill the cavity were recorded. Over 24 months, the teeth were clinically evaluated every six months and radiographically every 12 months by two calibrated and blinded evaluators using the United States public health service (USPHS)-Ryge criteria. The two-sided 95% confidence interval (CI) for the difference in success rate was considered to assess non-inferiority, and the margin was set at -18%. The linear mixed model and Firth’s logistic regression model were used for data analysis (P < 0.05).ResultsAfter 24 months, 86 teeth (43 per group) were evaluated. The mean PI score was 1.1(± 0.9), while DMFT/dmft was 0.35 (± 0.74) and 6.55 (± 2.25) respectively. The clinical and radiographic success rate of Dyract vs. ACTIVA was 95.3% and 88.3% vs. 93% and 86%, respectively. The two-sided 95% CI for the difference in success rate (-2.3%) was − 3.2 to 1.3% and didn’t reach the predetermined margin of -18% which had been anticipated as the non-inferiority margin. Clinically, ACTIVA had a significantly better colour match (P = 0.002) but worse marginal discolouration (P = 0.0143). There were no significant differences regarding other clinical or radiographic criteria (P > 0.05). ACTIVA took significantly less placement time than Dyract, with a mean difference of 2.37 (± 0.63) minutes (P < 0.001).ConclusionThe performance of ACTIVA was not inferior to Dyract and both materials had a comparable high clinical and radiographic performance in children with high-caries experience. ACTIVA had a significantly better colour match but more marginal discolouration. It took significantly less time to be placed in the oral cavity.Trial registrationThe study was registered at ClinicalTrials.gov on 4 May 2018 (#NCT03516838).

Team performance during vacuum-assisted vaginal delivery: video review of obstetric multidisciplinary teams.

Vacuum extraction is generally considered an operator-dependent task, with most attention directed toward the obstetrician's technical abilities (1-3). Little is known about the effect of the team and non-technical skills on clinical outcomes in vacuum-assisted delivery. This study aimed to investigate whether the non-technical skills of obstetricians were correlated with their level of clinical performance via the analysis of video recordings of teams conducting actual vacuum extractions. We installed between two or three video cameras in each delivery room at Aarhus University Hospital and Horsens Regional Hospital and obtained 60 videos of teams managing vacuum extraction. Appropriate consent was obtained. Two raters carefully reviewed the videos and assessed the teams' non-technical skills using the Assessment of Obstetric Team Performance (AOTP) checklist, rating all items on a Likert scale score from 1 to 5 (1 = poor; 3 = average; and 5 = excellent). This resulted in a total score ranging from 18 to 90. Two different raters independently assessed the teams' clinical performance (adherence to clinical guidelines) using the TeamOBS-Vacuum-Assisted Delivery (VAD) checklist, rating each item (0 = not done, 1 = done incorrectly; and 2 = done correctly). This resulted in a total score with the following ranges (low clinical performance: 0-59; average: 60-84; and high: 85-100). Interrater agreement was analyzed using intraclass correlation (ICC), and the risk of high or low clinical performance was analyzed on a logit scale to meet the assumption of normality. Teams that received excellent non-technical scores had an 81% probability of achieving high clinical performance, whereas this probability was only 12% among teams with average non-technical scores (p < 0.001). Teams with a high clinical performance often had excellent behavior in the non-technical items of "team interaction," "anticipation," "avoidance fixation," and "focused communication." Teams with a low or average clinical performance often neglected to consider analgesia, had delayed abandonment of the attempted vaginal delivery and insufficient use of appropriate fetal monitoring. Interrater reliability was high for both rater-teams, with an ICC for the non-technical skills of 0.83 (95% confidence interval [CI]: 0.71-0.88) and 0.84 for the clinical performance (95% CI: 0.74-0.90). Although assisted vaginal delivery by vacuum extraction is generally considered to be an operator-dependent task, our findings suggest that teamwork and effective team interaction play crucial roles in achieving high clinical performance. Teamwork helped the consultant anticipate the next step, avoid fixation, ensure adequate analgesia, and maintain thorough fetal monitoring during delivery.

Tuning the Chemical and Electrochemical Properties of Paper-Based Carbon Electrodes by Pyrolysis of Polydopamine.

Electrochemical paper-based analytical devices represent an important platform for portable, low-cost, affordable, and decentralized diagnostics. For this kind of application, chemical functionalization plays a pivotal role to ensure high clinical performance by tuning surface properties and the area of electrodes. However, controlling different surface properties of electrodes by using a single functionalization route is still challenging. In this work, we attempted to tune the wettability, chemical composition, and electroactive area of carbon-paper-based devices by thermally treating polydopamine (PDA) at different temperatures. PDA films were deposited onto pyrolyzed paper (PP) electrodes and thermally treated in the range of 300-1000 °C. After deposition of PDA, the surface is rich in nitrogen and oxygen, it is superhydrophilic, and it has a high electroactive area. As the temperature increases, the surface becomes hydrophobic, and the electroactive area decreases. The surface modifications were followed by Raman, X-ray photoelectron microscopy (XPS), laser scanning confocal microscopy (LSCM), contact angle, scanning electron microscopy (SEM-EDS), electrical measurements, transmission electron microscopy (TEM), and electrochemical experiments. In addition, the chemical composition of nitrogen species can be tuned on the surface. As a proof of concept, we employed PDA-treated surfaces to anchor [AuCl4]- ions. After electrochemical reduction, we observed that it is possible to control the size of the nanoparticles on the surface. Our route opens a new avenue to add versatility to electrochemical interfaces in the field of paper-based electrochemical biosensors.

Development of a robust TaqMan probe-based one-step multiplex RT-qPCR for simultaneous detection of SARS-CoV-2 and Influenza A/B viruses

BackgroundDuring the coronavirus disease 2019 (COVID-19) pandemic, the simultaneous detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Influenza A, and Influenza B viruses is essential for rapid differential diagnosis in patients with similar symptoms, especially during “flu season” in the post-pandemic era. So far, several multiplex methods have been approved for the simultaneous detection of SARS-CoV-2, Influenza A, and Influenza B. However, due to the rapid mutation rate of the SARS-CoV-2 genome and the emergence of new variants, existing methods must be improved and updated.MethodsTo identify a highly conserved region in the SARS-CoV-2 N-gene, a genomic survey was performed to increase the sensitivity and specificity of primer and probe sets targeting the SARS-CoV-2 genome. The 95% LLOD (95% lower limits of detection) were calculated by probit analysis. A total of 70 predetermined clinical samples using singleplex RT-qPCR assays, were included. The clinical performance of the multiplex RT-qPCR assay was determined and compared with a commercial multiplex kit. The Cohen’s kappa coefficient, P-value (McNemar’s test), Passing-Bablok regression, and Bland Altman agreement analysis were determined to monitor the agreement of the assays.ResultsThe novel SARS-CoV-2 primer and probe set designed in this assay was able to detect all variants of concern (VOCs) and variants of interest (VOIs) with high analytical and clinical performance. The 95% LLOD for the multiplex RT-qPCR was 20 copies per reaction for the N gene of SARS-CoV-2, 2 copies per reaction for M1 gene of Influenza A and NS1 gene of Influenza B. The diagnostic sensitivity of the multiplex RT-qPCR was 94.4%, 93.7%, and 100% for the detection of SARS-CoV-2, Influenza A, and Influenza B genomes, respectively. Moreover, the specificity was identical (100%) in both assays. According to the agreement analysis results, there was no statistical difference between our multiplex assay and the commercial kit.ConclusionsIn this study, we developed a novel in-house made multiplex RT-qPCR assay, with high sensitivity, specificity, and reliability for the diagnosis of SARS-CoV-2 infection in clinical samples. This is valuable during Influenza seasons when influenza co-circulates with SARS-CoV-2, as it saves costs, time, and thus specific and timely treatment of patients.

Development and evaluation of the automated multipurpose molecular testing system PCRpack for high-throughput SARS-CoV-2 testing

ABSTRACT Increasing the reliable testing capacity for SARS-CoV-2 is important for the diagnosis and control of COVID-19. We developed an automated, customizable, easy-to-implement molecular testing system, named PCRpack, for the high-throughput testing of SARS-CoV-2. PCRpack includes a liquid handling instrument enclosed in a negative-pressure clean booth (Biomek i5), a laboratory information management system (SimpPCR), other equipment, and documents that are needed for testing operation. An in vitro diagnostic assay was employed to detect SARS-CoV-2. System performance was evaluated based on liquid handling accuracy and precision, analytical sensitivity, clinical diagnostic performance, and testing capacity per day. Clinical diagnostic performance was determined against the reference extraction-based reverse transcription-PCR assay using 3,965 upper respiratory samples. Analytical sensitivity analysis showed a lower limit of detection of 1,000 genome copies/mL of sample. The accuracy and precision of sample or reagent dispensing in PCRpack ranged from −2.24% to 0.73% and 0.83% to 4.52%, respectively. In the evaluation of clinical samples, PCRpack showed a positive percent agreement of 96.6% and a negative percent agreement of 100% compared with the reference assay. The average turnaround times per 94 samples and the maximum numbers of tests within an 8-hour shift of one operator were 2 hours and 28 minutes vs 2 hours and 1 minute and 564 vs 376 samples for PCRpack and the manual method, respectively. The developed PCRpack system shows high liquid handling and clinical diagnostic performance and is a promising testing system for increasing the SARS-CoV-2 testing capacity and testing future emerging pathogens. IMPORTANCE Accurate and fast molecular testing is important for the diagnosis and control of COVID-19. During patient surges in the COVID-19 pandemic, laboratories were challenged by a higher demand for molecular testing under skilled staff shortages. We developed an automated multipurpose molecular testing system, named PCRpack, for the rapid, high-throughput testing of infectious pathogens, including SARS-CoV-2. The system is provided in an all-in-one package, including a liquid handling instrument, a laboratory information management system, and other materials needed for testing operation; is highly customizable; and is easily implemented. PCRpack showed robust liquid handling performance, high clinical diagnostic performance, a shorter turn-around time with minimal hands-on time, and a high testing capacity. These features contribute to the rapid implementation of the high-performance and high-throughput molecular testing environment at any phase of the pandemic caused by SARS-CoV-2 or future emerging pathogens.

MEDIATING ROLE OF EMOTIONAL INTELLIGENCE BETWEEN THE RELATIONSHIP OF OCCUPATIONAL STRESS AND CLINICAL PERFORMANCE AMONG NURSES

Nurses are going through the extensive physical and emotional burden, directing them to occupational stress. The shortfall of nurses is alarming after the pandemic of COVID -19. This study aimed to explore the ways to reduce occupational stress among nurses. It will help to alleviate their clinical performance. Frame-work of emotional intelligence is used as a mediating variable between occupational stress and clinical performance among nurses. This cross-sectional study was carried out in Multan, Pakistan in 2022. The population was nurses (currently employed) from four main hospitals (C.M.H, Nishter, Children Complex, and Cardiology Center). The sample size was 251 respondents and the survey method was used to gain data. Data were analyzed through SPSS. The results indicate that occupational stress is negatively correlated with emotional intelligence and clinical performance among nurses. Emotional intelligence is positively correlated with clinical performance. The significant impact of occupational stress on clinical performance is significant. Emotional intelligence had a fully mediating role between occupational stress and clinical performance among nurses. Married nurses reported to have higher occupational stress and lower emotional intelligence and clinical performance while nurses below 30 years reported high emotional intelligence and clinical performance but low occupational stress. Developing emotional intelligence and providing support and opportunities are crucial strategies to reduce occupational stress among nurses.

A-250 Rapid molecular Identification of Herpes Simplex, Varicella-zoster, and Enteroviruses from Cerebrospinal Fluid

Abstract Background Accurate and efficient molecular testing of viral meningitis/encephalitis is crucial for proper patient care. Here we describe the clinical evaluation of the GenomEra® HSV-1/2, VZV + EV Assay Kit (Uniogen, Finland) allowing simultaneous detection of four key viruses responsible for causing meningitis/encephalitis, namely HSV-1 and HSV-2, VZV, and enteroviruses. Methods The study was carried out at three European institutions in 2022, with a total of 193 frozen, anonymized leftover cerebrospinal fluid (CSF) specimens analyzed retrospectively. For the GenomEra HSV-1/2, VZV + EV Assay Kit, 50 µL of CSF was mixed with lysis buffer in a 1:1 ratio, allowed to incubate for 1 min at room temperature, and then filtered by a 1-min centrifugation through an Extraction Column utilizing size-exclusion chromatography. A 35-µL sample of the flow-through was applied into the Test Chip and analyzed using the GenomEra CDX System. The cotemporally performed comparison tests included the FilmArray Meningitis/Encephalitis (ME) panel (bioMérieux), Xpert® EV Assay (Cepheid), artus VZV assay (Qiagen), and a well-established, validated non-commercial real-time RT-PCR assay for the detection of HSV-1/2, VZV, and EV. Results The GenomEra HSV-1/2, VZV + EV Assay Kit produced results in 70 min with a sensitivity and specificity of 92.2% (95% CI: 82.7–97.4%) and 99.9% (95% CI: 99.2–100%), respectively, as compared to the reference tests. Of the discordant results, five tested negative with the GenomEra assay, whereas the reference tests produced low positive results (Ct values ≥ 35). In addition, one specimen yielded a positive signal for VZV while remaining negative with the reference tests. Conclusion The GenomEra HSV-1/2, VZV + EV Assay Kit showed a high overall specificity and a high level of sensitivity particularly for herpes simplex and varicella-zoster viruses. For enteroviruses, while the specificity reached 100%, the sensitivity was not as high as with the reference methods. The high clinical performance, together with the simple sample preparation protocol and short turnaround time make the GenomEra assay a competitive molecular test especially for small and medium-sized laboratories that may not have a specialist in molecular biology. In addition, the GenomEra assay only requires a small amount of sample, conserving the valuable specimens for additional testing.

Screening of placenta accreta spectrum disorder using maternal serum biomarkers and clinical indicators: a case–control study

BackgroundPlacenta accreta spectrum (PAS) disorder is a major cause of postpartum hemorrhage-associated maternal and fetal death, and novel methods for PAS screening are urgently needed for clinical application.MethodsThe purpose of this study was to develop new methods for PAS screening using serum biomarkers and clinical indicators. A total of 95 PAS cases and 137 controls were enrolled in a case–control study as cohort one, and 44 PAS cases and 35 controls in a prospective nested case–control study were enrolled as cohort two. All subjects were pregnant women of Chinese Han population. Biomarkers for PAS from maternal blood samples were screened based on high-throughput immunoassay and were further validated in three phases of cohort one. Screening models for PAS were generated using maternal serum biomarkers and clinical indicators, and were validated in two cohorts. The expression levels of biomarkers were analyzed using histopathological and immunohistochemical (IHC) techniques, and gene expression was examined by QPCR in the human placenta. Binary logistic regression models were built, and the area under the curve (AUC), sensitivity, specificity, and Youden index were calculated. Statistical analyses and model building were performed in SPSS and graphs were generated in GraphPad Prism. The independent-sample t test was used to compare numerical data between two groups. For nonparametric variables, a Mann–Whitney U test or a X2 test was used.ResultsThe results demonstrated that the serum levels of matrix metalloproteinase-1 (MMP-1), epidermal growth factor (EGF), and vascular endothelial growth factor-A (VEGF-A) were consistently higher, while the level of tissue-type plasminogen activator (tPA) was significantly lower in PAS patients compared with normal term controls and patients with pre-eclampsia (PE) and placenta previa (PP). IHC and QPCR analysis confirmed that the expression of the identified biomarkers significantly changed during the third trimester in human placenta. The generated screening model combining serum biomarkers and clinical indicators detected 87% of PAS cases with AUC of 0.94.ConclusionsSerum biomarkers can be used for PAS screening with low expense and high clinical performance; therefore, it may help to develop a practicable method for clinical prenatal PAS screening.

The nailfold dermoscopy findings of patients with atypical haemolytic uremic syndrome

Hemolytic uremic syndrome (HUS) is a severe disease characterized by microangiopathic anemia, thrombocytopenia, and acute renal failure. Atypical HUS (aHUS) that results due to genetic disorders of the alternative complement pathway results in inflammation, endothelial damage, and kidney injury. Therefore, simple and non-invasive tests are needed to evaluate the activity of the disease by assessing the microvascular structure in aHUS. A dermoscope (×10) is an inexpensive and easily portable device used to visualize nailfold capillaries and has high clinical performance and interobserver reliability. In this study, the nailfold capillaries of patients with aHUS who were in remission under eculizumab treatment were examined, and the findings were compared to those of a healthy control group to evaluate disease characteristics. All children with aHUS had decreased capillary densities even if they were in remission. This may be indicative of ongoing inflammation and microvascular damage in aHUS. A dermoscopy can be used as a screening tool for disease activity in patients with aHUS.

Clinical Performance of Cobas 6800 for the Detection of High-Risk Human Papillomavirus in Urine Samples.

Testing for high-risk human papillomavirus (HPV) as part of primary cervical cancer screening has become more common recently. The Cobas 6800, an FDA-approved cervical screening platform, detects 14 high-risk HPVs, including HPV16 and HPV18. However, this test is limited to only women, which leads to low screening rates in trans men and other non-binary people. The cervical screening of trans men and other genders, especially those lying on the female-to-male spectrum, is equally important. Furthermore, cisgender males, particularly homosexuals, are also prone to chronic HPV infections and serve as HPV carriers, transmitting it to women and other men through sexual contact. Another limitation of the test is its invasive specimen collection, which induces discomfort and genital dysphoria. Therefore, there is a need for an innovative, less invasive method that would allow the sampling process to be more comfortable. In this study, we assess the performance of the Cobas 6800 for high-risk HPV detection in urine samples spiked with HPV16, HPV18, and HPV68. The limit of detection (LOD) was calculated using a dilution series (1.25-10,000 copies/mL) over a course of three days. Furthermore, the clinical validation was performed by calculating sensitivity, specificity, and accuracy. The limit of detection ranged from 50-1000 copies/mL depending upon the genotype. Moreover, the urine test demonstrated a high clinical sensitivity of 93%, 94%, and 90% for HPV16, HPV18, and HPV68, with 100% specificity. The overall percent agreement was calculated to be 95% for both HPV16 and HPV18, and 93% for HPV68. The high concordance, reproducibility, and clinical performance of the current assay suggest that the urine-based HPV test fulfills the requirements for its use in primary cervical screening. Moreover, it has the potential to be used for mass screening to not only identify high-risk individuals, but also to monitor vaccine effectiveness.

The Utility of Urodynamic Studies in Neuro-Urological Patients

The utility of a clinical tool lies in its clinical performance evaluation and describes the relevance and usefulness of that tool in a medical setting. The utility of urodynamic and video-urodynamic studies in the management of specific urodynamic profiles in the diagnosis, treatment, and prognostic approach in neuro-urological patients is the focus of the current review. For this narrative review, a PubMed® search was performed by cross-referencing the keywords "urodynamics", "neurogenic bladder", "utility", "clinical utility" and "clinical performance" with various terms related to the management of neurogenic lower urinary tract dysfunction. Clinical practice guidelines and landmark reviews from the most renowned experts in the field were also used. Assessment of the utility of urodynamic study was performed during the diagnostic, therapeutic and prognostic steps of the neuro-urological patients' management. We focused on its clinical performance in the identification and evaluation of several unfavorable events, such as neurogenic detrusor overactivity, detrusor-sphincter dyssynergia, elevated detrusor leak point pressure and the presence of vesico-ureteral reflux, which may be indicators for a higher risk for the development of urological comorbidities. Despite the paucity of existing literature assessing the utility of urodynamic study-specifically video-urodynamic study-in neuro-urological patients, it does remain the gold standard to assess lower urinary tract function precisely in this patient category. With regard to its utility, it is associated with high clinical performance at every step of management. The feedback on possible unfavorable events allows for prognostic assessment and may lead us to question current recommendations.

Clinical Validation of a Novel T-Cell Receptor Sequencing Assay for Identification of Recent or Prior Severe Acute Respiratory Syndrome Coronavirus 2 Infection.

BackgroundWhile diagnostic, therapeutic, and vaccine development in the COVID-19 pandemic has proceeded at unprecedented speed, critical gaps in our understanding of the immune response to SARS-CoV-2 remain unaddressed by current diagnostic strategies.MethodsA statistical classifier for identifying prior SARS-CoV-2 infection was trained using >4000 SARS-CoV-2–associated TCRβ sequences identified by comparing 784 cases and 2447 controls from 5 independent cohorts. The T-Detect™ COVID assay applies this classifier to TCR repertoires sequenced from blood samples to yield a binary assessment of past infection. Assay performance was assessed in 2 retrospective (n = 346; n = 69) and 1 prospective cohort (n = 87) to determine positive percent agreement (PPA) and negative percent agreement (NPA). PPA was compared to 2 commercial serology assays, and pathogen cross-reactivity was evaluated.ResultsT-Detect COVID demonstrated high PPA in individuals with prior RT-PCR–confirmed SARS-CoV-2 infection (97.1% 15 + days from diagnosis; 94.5% 15 + days from symptom onset), high NPA (∼100%) in presumed or confirmed SARS-CoV-2 negative cases, equivalent or higher PPA than 2 commercial serology tests, and no evidence of pathogen cross-reactivity.ConclusionT-Detect COVID is a novel T-cell immunosequencing assay demonstrating high clinical performance for identification of recent or prior SARS-CoV-2 infection from blood samples, with implications for clinical management, risk stratification, surveillance, and understanding protective immunity and long-term sequelae.

Teamwork and Adherence to Guideline on Newborn Resuscitation-Video Review of Neonatal Interdisciplinary Teams.

BackgroundLittle is known about the importance of non-technical skills for the adherence to guidelines, when teams of midwives, obstetricians, anesthesiologists, and pediatricians resuscitate and support the transition of newborns. Non-technical skills are competences underpinning successful teamwork in healthcare. These are usually referred to as leadership, situational awareness, communication, teamwork, decision making, and coping with stress and fatigue.ObjectiveBy review of videos of teams managing newborns with difficult transition, we aimed to investigate whether the level of the teams' non-technical skills was associated with the degree of adherence to guidelines for newborn resuscitation and transitional support at birth.MethodsFour expert raters independently assessed 43 real-life videos of teams managing newborns with transitional difficulties, two assessed the non-technical score and two assessed the clinical performance. Exposure was the non-technical score, obtained by the Global Assessment Of Team Performance checklist (GAOTP). GAOTP was rated on a Likert Scale 1–5 (1 = poor, 3 = average and 5 = excellent). The outcome was the clinical performance score of the team assessed according to adherence of the European Resuscitation Counsel (ERC) guideline for neonatal resuscitation and transitional support. The ERC guideline was adapted into the checklist TeamOBS-Newborn to facilitate a structured and simple performance assessment (low score 0–60, average 60–84, high 85–100). Interrater agreement was analyzed by intraclass correlation (ICC), Bland-Altman analysis, and Cohen's kappa weighted. The risk of high and low clinical performance was analyzed on the logit scale to meet the assumptions of normality and constant standard deviation.ResultsTeams with an excellent non-technical score had a relative risk 5.5 [95% confidence interval (CI) 2.4–22.5] of high clinical performance score compared to teams with average non-technical score. In addition, we found a dose response like association. The specific non-technical skills associated with the highest degree of adherence to guidelines were leadership and teamwork, coping with stress and fatigue, and communication with parents. Inter-rater agreement was high; raters assessing non-technical skills had an interclass coefficient (ICC) 0.88 (95% CI 0.79–0.94); the neonatologists assessing clinical performance had an ICC of 0.81 (95% CI 0.66–0.89).ConclusionTeams with an excellent non-technical score had five times the chance of high clinical performance compared to teams with average non-technical skills. High performance teams were characterized by good leadership and teamwork, coping with stress, and fatigue and communication with parents.

144. Clinical Validation and Performance of a T-cell Immunosequencing Assay to Identify Past SARS-CoV-2 Infection

BackgroundOur understanding of the SARS-CoV-2 immune response has critical gaps that are inadequately addressed with available tools. We report the clinical performance of T-Detect COVID, the first T-cell assay to identify prior SARS-CoV-2 infection using T-cell receptor (TCR) sequencing and repertoire profiling from whole blood samples. MethodsThe T-Detect COVID assay combines high-throughput immunosequencing of the TCRß gene from blood samples with a statistical classifier demonstrating 99.8% specificity for identifying prior SARS-CoV-2 infection. The assay was employed in several retrospective and prospective cohorts to assess primary and secondary Positive Percent Agreement (PPA) with SARS-CoV-2 RT-PCR (N=205; N=77); primary and secondary Negative Percent Agreement (NPA; N=87; N=79); PPA compared to SARS-CoV-2 serology (N=55); and pathogen cross-reactivity (N=38). The real-world performance of the test was also evaluated in a retrospective review of test ordering (N=69) at a single primary care clinic in Park City, Utah. ResultsIn validation studies, T-Detect COVID demonstrated high PPA (97.1% ≥15 days from diagnosis) in subjects with prior PCR-confirmed SARS-CoV-2 infection; high NPA (~100%) in SARS-CoV-2 negative cases; equivalent or higher PPA with RT-PCR compared to two commercial EUA antibody tests; and no evidence of pathogen cross-reactivity. Review of assay use in a single clinic showed 100% PPA with RT-PCR in individuals with past confirmed SARS-CoV-2 vs. 85.7% for antibody testing, 100% agreement with positive antibody results, and positive results in 2/4 convalescent subjects with seroreversion to a negative antibody. In addition, 12/69 (17.3%) individuals with absent or negative RT-PCR tested positive by T-Detect COVID, nearly all of whom had compatible symptoms and/or exposure. TCR positivity was observed up to 12+ months (median 118 days) from the date of positive RT-PCR. ConclusionA T-cell immunosequencing assay shows high clinical performance for identifying past SARS-CoV-2 infection from whole blood samples. This assay can provide additional insights on the SARS-CoV-2 immune response, with practical implications for clinical management, risk stratification, surveillance, assessing vaccine immunity, and understanding long-term sequelae. Disclosures Sudeb C. Dalai, MD, PhD, Adaptive Biotechnologies (Employee, Shareholder) Jennifer N. Dines, MD, Adaptive Biotechnologies (Employee, Shareholder) Thomas M. Snyder, PhD, Adaptive Biotechnologies (Employee, Shareholder) Rachel M. Gittelman, PhD, Adaptive Biotechnologies (Employee, Shareholder) Tera Eerkes, PhD, Adaptive Biotechnologies (Employee, Shareholder) Pashmi Vaney, PhD, Adaptive Biotechnologies (Employee, Shareholder) Sally Howard, PhD, Adaptive Biotechnologies (Employee, Shareholder) Kipp Akers, PhD, Adaptive Biotechnologies (Employee, Shareholder) Lynell Skewis, PhD, Adaptive Biotechnologies (Employee, Shareholder) Anthony Monteforte, PhD, Adaptive Biotechnologies (Employee, Shareholder) Pamela R. Witte, PhD, Adaptive Biotechnologies (Employee, Shareholder) Cristina Wolf, PhD, Adaptive Biotechnologies (Employee, Shareholder) Hans Nesse, PhD, Adaptive Biotechnologies (Employee, Shareholder) Jia Qadeer, PhD, Adaptive Biotechnologies (Employee, Shareholder) Sarah Duffy, PhD, Adaptive Biotechnologies (Employee, Shareholder) Emily Svejnoha, PhD, Adaptive Biotechnologies (Employee, Shareholder) Caroline Taromino, PhD, Adaptive Biotechnologies (Employee, Shareholder) Ian M. Kaplan, PhD, Adaptive Biotechnologies (Employee, Shareholder) John Alsobrook, MD, Adaptive Biotechnologies (Employee, Shareholder) Thomas Manley, MD, Adaptive Biotechnologies (Employee, Shareholder) Lance Baldo, MD, Adaptive Biotechnologies (Employee, Shareholder, Leadership Interest)