Abbott ID NOW™ COVID-19 assay: do not discard the swab

We compared the performance of ID NOW™ COVID-19 assay nasal swabs with RT-PCR of nasopharyngeal swabs for SARS-CoV-2 in an outbreak setting, determining whether addition of RT-PCR of residual nasal swabs (rNS) (post ID NOW™ elution) would increase overall analytic sensitivity. Devices were placed at 2 long term and 1 acute care sites and 51 participants were recruited. Prospective paired nasopharyngeal and nasal samples were collected for RT-PCR and ID NOW™. ID NOW™ had a positive and negative categorical agreement of 86% and 93% compared to RT-PCR of nasopharyngeal swabs. Sensitivity and specificity of the ID NOW™ was 86% and 100%, positive and negative predictive value was 100% and 95% (COVID-19 positivity rate: 8%). Addition of rNS RT-PCR increased the positive and negative categorical agreement to 93% and 97%. Based on these results, we propose an alternative workflow which includes complementary testing of rNS on a secondary assay. © 2022 Elsevier Inc.

The added predictive role of echocardiography in patients with mild or moderate Coronavirus Disease 2019

Aims: Recently, several therapeutic agents have decreased the progression to critical disease in patients with mild/moderate COVID-19. However, their use is limited to patients with ≥1 clinical risk factor. We aimed to evaluate echocardiographic features that may aid in risk stratification for patients with mild/moderate COVID-19. Methods: 278 consecutive patients with mild/moderate COVID-19 underwent prospective clinical and echocardiographic examination, ≤7 days of symptoms, as part of a predefined protocol. Analysis to identify echocardiographic predictors of outcome was performed. Results: In the multivariable risk model, E/e′, TAPSE, and pulmonary acceleration time (PAT) were associated with the composite outcome (p = 0.01, 0.005, 0.05, respectively). Stepwise analyses showed that the addition of echocardiography on top of having ≥1 clinical risk factor and even using each parameter separately improved the prediction of outcomes. If patients were re-categorized as high risk only if having both ≥1 clinical and ≥ 1 echocardiography risk parameter (E/e′ > 8, TAPSE<1.8 cm, PAT<90 msec), or even one echo parameter separately, then specificity, positive predictive value, and accuracy improved. If patients were re-classified as high risk if having either ≥1 clinical risk factor or ≥ 1 high-risk echocardiography parameter, all five individuals who were missed by the ≥1 risk factor "rule”, were correctly diagnosed as high risk. Similar analyses, including only patients with mild disease, showed that the addition of TAPSE improved the prediction of outcomes. Conclusions: In patients with mild/moderate COVID-19, a very limited echocardiographic exam is sufficient for improved outcome prediction, and may improve resource allocation for new anti-COVID-19 agents. Translational aspect of the work: We show that among patients with mild/moderate COVID-19, several easily obtained echocardiographic findings are strongly correlated with mortality or progression to the need for invasive/non-invasive mechanical ventilation, even when adjusted for the presence or absence of ≥1 clinical risk factor. Furthermore, even a limited echocardiographic exam is sufficient to develop a strategy of risk stratification. We believe that our data have important implications for the clinicians involved in the acute treatment of patients with COVID-19. © 2022 Elsevier B.V.

Fast and visual detection of nucleic acids using a one-step RPA-CRISPR detection (ORCD) system unrestricted by the PAM

CRISPR-Cas12a (Cpf1) is widely used for pathogen detection. However, most Cas12a nucleic acid detection methods are limited by a PAM sequence requirement. Moreover, preamplification and Cas12a cleavage are separate. Here, we developed a one-step RPA-CRISPR detection (ORCD) system unrestricted by the PAM sequence with high sensitivity and specificity that offers one-tube, rapid, and visually observable detection of nucleic acids. In this system, Cas12a detection and RPA amplification are performed simultaneously, without separate preamplification and product transfer steps, and 0.2 copies/μL of DNA and 0.4 copies/μL of RNA can be detected. In the ORCD system, the activity of Cas12a is the key to the nucleic acid detection;specifically, reducing Cas12a activity increases the sensitivity of ORCD assay detection of the PAM target. Furthermore, by combining this detection technique with a nucleic acid extraction-free method, our ORCD system can be used to extract, amplify and detect samples within 30 min, as verified with tests of 82 Bordetella pertussis clinical samples with a sensitivity and specificity of 97.30% and 100% compared with PCR. We also tested 13 SARS-CoV-2 samples with RT-ORCD, and the results were consistent with RT–PCR.

Oculomotor, vestibular, reaction time, and cognitive tests as objective measures of neural deficits in patients post COVID-19 infection

Objective: An alarming proportion (>30%) of patients affected by SARS-CoV-2 (COVID-19) continue to experience neurological symptoms, including headache, dizziness, smell and/or taste abnormalities, and impaired consciousness (brain fog), after recovery from the acute infection. These symptoms are self-reported and vary from patient to patient, making it difficult to accurately diagnose and initiate a proper treatment course. Objective measures to identify and quantify neural deficits underlying the symptom profiles are lacking. This study tested the hypothesis that oculomotor, vestibular, reaction time, and cognitive (OVRT-C) testing using eye-tracking can objectively identify and measure functional neural deficits post COVID-19 infection. Methods: Subjects diagnosed with COVID-19 (n = 77) were tested post-infection with a battery of 20 OVRT-C tests delivered on a portable eye-tracking device (Neurolign Dx100). Data from 14 tests were compared to previously collected normative data from subjects with similar demographics. Post-COVID subjects were also administered the Neurobehavioral Symptom Inventory (NSI) for symptom evaluation. Results: A significant percentage of post COVID-19 patients (up to 86%) scored outside the norms in 12 out of 14 tests, with smooth pursuit and optokinetic responses being most severely affected. A multivariate model constructed using stepwise logistic regression identified 6 metrics as significant indicators of post-COVID patients. The area under the receiver operating characteristic curve (AUC) was 0.89, the estimated specificity was 98% (with cutoff value of 0.5) and the sensitivity was 88%. There were moderate but significant correlations between NSI domain key variables and OVRT-C tests. Conclusions: This study demonstrates the feasibility of OVRT-C testing to provide objective measures of neural deficits in people recovering from COVID-19 infection. Such testing may serve as an efficient tool for identifying hidden neurological deficits post COVID-19, screening patients at risk of developing long COVID, and may help guide rehabilitation and treatment strategies.

Association of Vitamin D and Secondary Infection in COVID-19

Introduction: Vitamin D plays a role in the modulation of cytokine release, inflammation, innate and adaptive immunity. It has been frequently discussed that the hyperinflammatory response that causes acute respiratory distress syndrome or other organ damage due to SARS-CoV-2 at the beginning of the pandemic can be modulated by the adequacy of vitamin D. The relationship of vitamin D with many conditions such as mortality, number of intensive care unit stays, disease severity, and organ damage has been investigated, but the information on its effect on secondary infections that occur during the course of the disease is limited. In this study, it was aimed to reveal the relationship of vitamin D with secondary infections that occur during the course of COVID-19 disease. Materials and Methods: Medical records of patients hospitalized in the COVID-19 pandemic service with the diagnosis of COVID-19 were evaluated retrospectively. Results: One hundred eighty-one patients were included in the study. The mean of 25(OH) vitamin D was found to be 18.76 ± 9.82 ng/mL. When 25-hydroxy vitamin D was compared with gender, disease severity, mortality, need for mechanical ventilation and presence of symptoms, no statistically significant difference was found (p> 0.05). The medical data of the patients during their hospitalization were analyzed and secondary infection was detected in 14.9% (n= 27). When 25-hydroxy vitamin D and the presence of secondary infection were compared, the 25(OH)D vitamin level of those with secondary infection was found to be low and this was found to be statistically significant (p= 0.016). As a result of the evaluation made by ROC analysis, 25-hydroxy vitamin D was found to have a diagnostic value in predicting positive culture results in COVID-19 patients (AUC= 0.771, 95% Confidence Interval= 0.612-0.810, p= 0.003, p< 0.05). Conclusion: While vitamin D continues to be an important topic of discussion in COVID-19 disease due to its effects on the immune system, it should not be forgotten that low vitamin D increases the risk of secondary infection developing in the course of COVID-19 and this may have an impact on prognosis.

The Biofire® Filmarray® Pneumonia Plus panel for management of lower respiratory tract infection in mechanically-ventilated patients in the COVID-19 era: a diagnostic and cost-benefit evaluation

We assessed the diagnostic performance of the Biofire® Filmarray® Pneumonia Plus panel (FA-PP) compared to standard culture in Intensive Care Unit patients with suspected ventilator-associated lower respiratory tract infection in the COVID-19 era. We determined whether its implementation in routine diagnostic algorithms would be cost-beneficial from a hospital perspective. Of 163 specimens, 96 (59%) returned negative results with FA-PP and conventional culture, and 29 specimens (17.8%) were positive with both diagnostic methods and yielded concordant qualitative bacterial identification/isolation. Thirty-nine specimens (23.9%) gave discordant results (positive via FA-PP and negative via culture). Real-life adjustments of empirical antimicrobial therapy (EAT) after FA-PP results resulted in additional costs beyond EAT alone of 1868.7 €. Adequate EAT adjustments upon FA-PP results would have resulted in a saving of 6675.8 €. In conclusion, the data presented supports the potential utility of FA-PP for early EAT adjustment in patients with ventilator-associated lower respiratory tract infection. © 2022 Elsevier Inc.

Nail ridging in rheumatoid arthritis patients and relation to disease activity: An integrated rheumatology-dermatology multi-centre study

Aim of the work: To evaluate the frequency of nail ridging (NR) in patients with rheumatoid arthritis (RA) and to study its relation to disease activity. Patients and methods: 230 RA patients and 97 matched controls from Helwan, Ain Shams and Mansoura university hospitals were studied. Disease activity score (DAS28) was assessed. NR has been searched for in all patients. The number of affected fingers was recorded. NR was determined by a magnifying lens, seen by naked eye or seen and felt. Dermoscopic photography of the NR using Dermalite DL4 3Gen dermatoscope has been recorded. Results: The median age of patients was 49 years (42–58 years);they were 221 females and 19 males (F:M 11.1:1) with a disease duration 9 years (5–11 years). Their DAS28 was 3.6 (2.9–4.6). NR was significantly increased in RA cases vs. control;73% vs 20%;p < 0.001. In patients, NR was detected by a magnifying lens in 32.6%, seen in 27% and seen and felt in 13.5%. Joint deformities were significantly higher in those with NR. DAS28 was a significant independent predictor of NR;for every one-point increase in DAS28, there was a 153 times higher odds to exhibit NR at a sensitivity of 93.5%, specificity 80.3% and at a diagnostic accuracy of 90%. Conclusion: NR is a frequent finding in RA. An integrated rheumatological- dermatological clinical evaluation may be helpful and further studies are required to prove the importance of this sign for follow up of RA patients.

High-resolution anoscopy predictive modeling of anal canal cancer response after definitive chemoradiotherapy in COVID19 era

Purpose: To develop a predictive index model, integrating both clinical and high-resolution anoscopy (HRA) features to further personalize the decision making process in anal canal carcinoma in COVID19 era. Methods and materials: We assess HRA parameters after definitive chemoradiotherapy in patients with anal canal malignant lesions. Results: HRA features could be important to assess the effect of CRT and a risk stratification system should be introduced in clinical practice to better allocate therapeutic interventions. Conclusion: To our knowledge this is the first proposal for HRA findings in anal canal cancer after definitive CRT. We believe that a risk score can be useful to estimate the risk of treatment failure (in term of persistence disease and/or recurrence) and its clinical relevance should not to be underestimated. © 2022

Noninvasive Physiologic Assessment of Cardiac Allograft Vasculopathy Is Prognostic for Post-Transplant Events

Background: Cardiac allograft vasculopathy (CAV) causes impaired blood flow in both epicardial coronary arteries and the microvasculature. A leading cause of post-transplant mortality, CAV affects 50% of heart transplant recipients within 10 years of heart transplant. Objectives: This analysis examined the outcomes of heart transplant recipients with reduced myocardial blood flow reserve (MBFR) and microvascular CAV detected by 13N-ammonia positron emission tomography (PET) myocardial perfusion imaging. Methods: A total of 181 heart transplant recipients who underwent PET to assess for CAV were included with a median follow-up of 4.7 years. Patients were classified into 2 groups according to the total MBFR: >2.0 and ≤2.0. Microvascular CAV was defined as no epicardial CAV detected by PET and/or coronary angiography, but with an MBFR ≤2.0 by PET. Results: In total, 71 (39%) patients had an MBFR ≤2.0. Patients with an MBFR ≤2.0 experienced an increased risk for all outcomes: 7-fold increase in death or retransplantation (HR: 7.05;95% CI: 3.2-15.6;P < 0.0001), 12-fold increase in cardiovascular death (HR: 12.0;95% CI: 2.64-54.12;P = 0.001), and 10-fold increase in cardiovascular hospitalization (HR: 10.1;95% CI: 3.43-29.9;P < 0.0001). The 5-year mean survival was 302 days less than those with an MBFR >2.0 (95% CI: 260.2-345.4 days;P < 0.0001). Microvascular CAV (adjusted HR: 3.86;95% CI: 1.58-9.40;P = 0.003) was independently associated with an increased risk of death or retransplantation. Conclusions: Abnormal myocardial blood flow reserve, even in the absence of epicardial CAV, identifies patients at a high risk of death or retransplantation. Measures of myocardial blood flow provide prognostic information in addition to traditional CAV assessment.

Monocyte Distribution Width (MDW) as a biomarker of sepsis: An evidenced-based laboratory medicine approach

Monocyte Distribution Width (MDW) is a new generation cell blood count parameter providing a measure of monocyte anisocytosis. In the last decades, it has emerged as a reliable biomarker of sepsis in the acute setting, especially emergency department, and intensive care unit. MDW has several advantages over commonly used sepsis biomarkers, including low-cost, ease and speed of measurement. The clinical usefulness of MDW has been established in several studies and some clinical laboratory medicines have already implemented it in their routine. In this article, we describe the analytical and clinical features of MDW to guide its appropriate use in clinical practice by integrating the research evidence with real-world laboratory experience. The proper use of a biomarker is critical for improving patients' care and outcome as well as ensuring healthcare quality. © 2022

Estimating the extent of asymptomatic covid-19 and its potential for community transmission: Systematic review and meta-analysis

Background: Knowing the prevalence of true asymptomatic coronavirus disease 2019 (COVID-19) cases is critical for designing mitigation measures against the pandemic. We aimed to synthesize all available research on asymptomatic cases and transmission rates. Methods: We searched PubMed, Embase, Cochrane COVID-19 trials, and Europe PMC for primary studies on asymptomatic prevalence in which (1) the sample frame includes at-risk populations, and;(2) follow-up was sufficient to identify pre-symptomatic cases. Meta-analysis used fixed-effects and random-effects models. We assessed risk of bias by combination of questions adapted from risk of bias tools for prevalence and diagnostic accuracy studies. Results: We screened 2,454 articles and included 13 low risk-of-bias studies from seven countries that tested 21,708 at-risk people, of which 663 were positive and 111 asymptomatic. Diagnosis in all studies was confirmed using a real-time reverse transcriptase–polymerase chain reaction test. The asymptomatic proportion ranged from 4% to 41%. Meta-analysis (fixed effects) found that the proportion of asymptomatic cases was 17% (95% CI 14% to 20%) overall and higher in aged care (20%;95% CI 14% to 27%) than in non-aged care (16%;95% CI 13% to 20%). The relative risk (RR) of asymptomatic transmission was 42% lower than that for symptomatic transmission (combined RR 0.58;95% CI 0.34 to 0.99, p = 0.047). Conclusions: Our one-in-six estimate of the prevalence of asymptomatic COVID-19 cases and asymptomatic transmission rates is lower than those of many highly publicized studies but still sufficient to warrant policy attention. Further robust epidemiological evidence is urgently needed, including in subpopulations such as children, to better understand how asymptomatic cases contribute to the pandemic.

Evaluating Methicillin-Resistant Staphylococcus aureus Polymerase Chain Reaction Nasal Screening as a Tool for Antimicrobial Stewardship

Introduction: Initiation of broad-spectrum empiric antibiotics is common when infection is suspected in hospitalized adults. The benefits of early utilization of effective antibiotics are well documented. However, the negative effects of inappropriate antibiotic use have led to antimicrobial stewardship mandates. Recent data demonstrate the utility of methicillin-resistant Staphylococcus aureus (MRSA) polymerase chain reaction (PCR) nasal screening to steward anti-MRSA empiric antibiotics in pneumonia. We hypothesize that MRSA PCR nasal swabs would also be effective to rule out other MRSA infection to effectively limit unnecessary antibiotics for any infectious source. Methods: We performed a single-center retrospective chart review of all adult patient encounters from October 2019-July 2021 with MRSA PCR nasal testing. We then reviewed all charts to evaluate for the presence of infections based on source cultures results, as the gold standard. Sensitivity, specificity, negative predictive value, and positive predictive value were calculated from 2 × 2 contingency tables. Results: Among all patients with MRSA nasal screening, 1189 patients had any infection. Prevalence of MRSA nasal carriage among patients screened was 12%. Prevalence of MRSA infection among all infections was 7.5%. MRSA nasal swabs demonstrated a negative predictive value of 100% for MRSA urinary tract infection, 97.9% for MRSA bacteremia, 97.8% for MRSA pneumonia, 92.1% for MRSA wound infection, and 96.6% for other MRSA infections. Overall, MRSA PCR nasal swabs had a sensitivity of 68.5%, specificity of 90.1%, positive predictive value of 23.7%, and negative predictive value of 98.5% for any infections. Conclusions: MRSA PCR nasal swabs have a high negative predictive value for all infections. Our data support the use of MRSA PCR nasal swabs to rule out MRSA infection and thereby allow early de-escalation of MRSA coverage in hospitalized patients requiring empiric antibiotics. Implementation of MRSA screening could decrease antibiotic-associated morbidity, resistance, and costs. More studies should be conducted to validate these results and support these findings. © 2022 Elsevier Inc.

Tinea Gladiatorum Detection With a Dermatophyte Test Strip

Objective: Determine sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and concordance of diafactory hs-TP (DTS) to detect tinea gladiatorum using direct potassium hydroxide (KOH) microscopy as the reference standard. Design: Prospective, comparative study. Setting: Seventeen Minnesota high schools during the winter wrestling season. Patients: Seventy-one consecutive high school wrestlers identified with a suspicious rash during skin inspection. Interventions: Samples were obtained from each rash for both DTS and direct KOH microscopy. Main Outcome Measures: Readings were recorded as positive or negative. Results: Direct KOH microscopy identified tinea gladiatorum in 35 of the 71 samples (46%). DTS sensitivity was 80% (95% confidence interval 63%-92%), and specificity was 82% (66%-92%). PPV was 85% (68%-95%), and NPV was 86% (72 %-91%). The DTS result was 83% concordant (72%-91%) with direct KOH microscopy. Conclusions: Similar to rapid Covid antigen tests, DTS required brief, basic training to perform and gave onsite results in 5 to 30 minutes. Although DTS is not approved for use in the United States by the FDA, concordance compared with direct KOH microscopy in diagnosing tinea gladiatorum was similar to results reported for DTS-TU in tinea unguium and tinea pedis. Further study comparing DTS to a reference standard using PCR plus direct microscopy is warranted. © 2022 Wolters Kluwer Health, Inc.

Evaluating a SARS-CoV-2 screening strategy based on serological tests

BACKGROUND: facing the SARS-CoV-2 epidemic requires intensive testing on the population to early identify and isolate infected subjects. Although RT-PCR is the most reliable technique to detect ongoing infections, serological tests are frequently proposed as tools in heterogeneous screening strategies. OBJECTIVES: to analyse the performance of a screening strategy proposed by the local government of Tuscany (Central Italy), which first uses qualitative rapid tests for antibody detection, and then RT-PCR tests on the positive subjects. METHODS: a simulation study is conducted to investigate the number of RT-PCR tests required by the screening strategy and the undetected ongoing infections in a pseudo-population of 500,000 subjects, under different prevalence scenarios and assuming a sensitivity of the serological test ranging from 0.50 to 0.80 (specificity 0.98). A compartmental model is used to predict the number of new infections generated by the false negatives two months after the screening, under different values of the infection reproduction number. RESULTS: assuming a sensitivity equal to 0.80 and a prevalence of 0.3%, the screening procedure would require on average 11,167 RT-PCR tests and would produce 300 false negatives, responsible after two months of a number of contagions ranging from 526 to 1,132, under the optimistic scenario of a reproduction number between 0.5 to 1. Resources and false negatives increase with the prevalence. CONCLUSIONS: the analysed screening procedure should be avoided unless the prevalence and the rate of contagion are very low. The cost and effectiveness of the screening strategies should be evaluated in the actual context of the epidemic, accounting for the fact that it may change over time.

Strong semantic segmentation for Covid-19 detection: Evaluating the use of deep learning models as a performant tool in radiography

Introduction: With the increasing number of Covid-19 cases as well as care costs, chest diseases have gained increasing interest in several communities, particularly in medical and computer vision. Clinical and analytical exams are widely recognized techniques for diagnosing and handling Covid-19 cases. However, strong detection tools can help avoid damage to chest tissues. The proposed method provides an important way to enhance the semantic segmentation process using combined potential deep learning (DL) modules to increase consistency. Based on Covid-19 CT images, this work hypothesized that a novel model for semantic segmentation might be able to extract definite graphical features of Covid-19 and afford an accurate clinical diagnosis while optimizing the classical test and saving time. Methods: CT images were collected considering different cases (normal chest CT, pneumonia, typical viral causes, and Covid-19 cases). The study presents an advanced DL method to deal with chest semantic segmentation issues. The approach employs a modified version of the U-net to enable and support Covid-19 detection from the studied images. Results: The validation tests demonstrated competitive results with important performance rates: Precision (90.96% ± 2.5) with an F-score of (91.08% ± 3.2), an accuracy of (93.37% ± 1.2), a sensitivity of (96.88% ± 2.8) and a specificity of (96.91% ± 2.3). In addition, the visual segmentation results are very close to the Ground truth. Conclusion: The findings of this study reveal the proof-of-principle for using cooperative components to strengthen the semantic segmentation modules for effective and truthful Covid-19 diagnosis. Implications for practice: This paper has highlighted that DL based approach, with several modules, may be contributing to provide strong support for radiographers and physicians, and that further use of DL is required to design and implement performant automated vision systems to detect chest diseases. © 2022 The College of Radiographers

Intelligent COVID-19 screening platform based on breath analysis

The spread of coronavirus disease 2019 (COVID-19) results in an increasing incidence and mortality. The typical diagnosis technique for severe acute respiratory syndrome coronavirus 2 infection is reverse transcription polymerase chain reaction, which is relatively expensive, time-consuming, professional, and suffered from false-negative results. A reliable, non-invasive diagnosis method is in urgent need for the rapid screening of COVID-19 patients and controlling the epidemic. Here we constructed an intelligent system based on the volatile organic compound (VOC) biomarkers in human breath combined with machine learning models. The VOC profiles of 122 breath samples (65 of COVID-19 infections and 57 of controls) were identified with a portable gas chromatograph-mass spectrometer. Among them, eight VOCs exhibited significant differences (p < 0.001) between the COVID-19 and the control groups. The cross-validation algorithm optimized support vector machine (SVM) model was employed for the prediction of COVID-19 infection. The proposed SVM model performed a powerful capability in discriminating COVID-19 patients from healthy controls, with an accuracy of 97.3%, a sensitivity of 100%, a specificity of 94.1%, and a precision of 95.2%, and an F1 score of 97.6%. The SVM model was also compared with other common machine models, including artificial neural network, k-nearest neighbor, and logistic regression, and demonstrated obvious superiority in the prediction of COVID-19 infection. Furthermore, user-friendly software was developed based on the optimized SVM model. The developed intelligent platform based on breath analysis provides a new strategy for the point-of-care screening of COVID and shows great potential in clinical application. © 2022 IOP Publishing Ltd.

PSTCNN: Explainable COVID-19 diagnosis using PSO-guided self-tuning CNN

Since 2019, the coronavirus disease-19 (COVID-19) has been spreading rapidly worldwide, posing an unignorable threat to the global economy and human health. It is a disease caused by severe acute respiratory syndrome coronavirus 2, a single-stranded RNA virus of the genus Betacoronavirus. This virus is highly infectious and relies on its angiotensin-converting enzyme 2-receptor to enter cells. With the increase in the number of confirmed COVID-19 diagnoses, the difficulty of diagnosis due to the lack of global healthcare resources becomes increasingly apparent. Deep learning-based computer-aided diagnosis models with high generalisability can effectively alleviate this pressure. Hyperparameter tuning is essential in training such models and significantly impacts their final performance and training speed. However, traditional hyperparameter tuning methods are usually time-consuming and unstable. To solve this issue, we introduce Particle Swarm Optimisation to build a PSO-guided Self-Tuning Convolution Neural Network (PSTCNN), allowing the model to tune hyperparameters automatically. Therefore, the proposed approach can reduce human involvement. Also, the optimisation algorithm can select the combination of hyperparameters in a targeted manner, thus stably achieving a solution closer to the global optimum. Experimentally, the PSTCNN can obtain quite excellent results, with a sensitivity of 93.65% ± 1.86%, a specificity of 94.32% ± 2.07%, a precision of 94.30% ± 2.04%, an accuracy of 93.99% ± 1.78%, an F1-score of 93.97% ± 1.78%, Matthews Correlation Coefficient of 87.99% ± 3.56%, and Fowlkes-Mallows Index of 93.97% ± 1.78%. Our experiments demonstrate that compared to traditional methods, hyperparameter tuning of the model using an optimisation algorithm is faster and more effective. © 2023 Centro Regional de Invest. Cientif. y Tecn.. All rights reserved.

Utility of Lung Perfusion SPECT/CT in Detection of Pulmonary Thromboembolic Disease: Outcome Analysis

Purpose: To evaluate the clinical outcome of Q-SPECT/CT in pulmonary thromboembolic disease. Methods: From Jan 2020 to Jan 2021, 30 consecutive patients (M:F = 8:22;median age = 52 year (21–89)) suspected of having acute pulmonary embolism (PE) or chronic thromboembolic pulmonary hypertension (CTEPH) were referred for non-contrasted Q-SPECT/CT. All patients were COVID-19 PCR negative. MSKCC Q-SPECT/CT and/or PISAPED criteria were used to determine the presence of thromboembolic disease in Q-SPECT/CT. Final diagnosis was made based on composite reference standards that included at least 2-month clinical cardiorespiratory assessment and follow-up imaging. Results: Q-SPECT/CT was positive in 19 patients: indeterminate in 1 and 10 were negative. Three false positive cases were observed during follow-up. Of the remaining 16 true positives, all patients' cardiorespiratory symptom were improved or stabilised after treatment with anticoagulants. The overall sensitivity, specificity, PPV, NPV and accuracy of Q-SPECT/CT were 100% (95% CI, 79.41–100%), 78.57% (95% CI, 49.20–95.34%), 84.21% (95% CI, 66.41–93.57%), 100% and 90.00% (95% CI, 73.47–97.89%) respectively. Conclusions: In the current COVID-19 pandemic, Q-SPECT/CT can be an alternative modality to detect pulmonary thromboembolic disease. Normal Q-SPECT/CT excludes pulmonary thromboembolic disease with high degree of certainty. However, false positive has been observed. © 2022, The Author(s), under exclusive licence to Korean Society of Nuclear Medicine.

Lung Ultrasound and High-Resolution Computed Tomography in Suspected COVID-19 Patients Admitted to the Emergency Department: A Comparison

Objective: To analyze the diagnostic accuracy of lung ultrasonography (LUS) and high-resolution computed tomography (HRCT), to detect COVID-19. Materials and Methods: This study recruited all patients admitted to the emergency medicine unit, due to a suspected COVID-19 infection, during the first wave of the COVID-19 pandemic. These patients also who underwent a standardized LUS examination and a chest HRCT. The signs detected by both LUS and HRCT were reported, as well as the sensitivity, specificity, positive predictive value, and negative predictive value for LUS and HRCT. Results: This cohort included 159 patients, 101 (63%) were diagnosed with COVID-19. COVID-19 patients showed more often confluent subpleural consolidations and parenchymal consolidations in lower lung regions of LUS. They also had "ground glass” opacities and "crazy paving” on HRCT, while pleural effusion and pulmonary consolidations were more common in non-COVID-19 patients. LUS had a sensitivity of 0.97 (95% CI 0.92–0.99) and a specificity of 0.24 (95% CI 0.07–0.5) for COVID-19 lung infections. HRCT abnormalities resulted in a 0.98 sensitivity (95% CI 0.92–0.99) and 0.1 specificity (95% CI 0.04–0.23) for COVID-19 lung infections. Conclusion: In this cohort, LUS proved to be a noninvasive, diagnostic tool with high sensitivity for lung abnormalities that were likewise detected by HRCT. Furthermore, LUS, despite its lower specificity, has a high sensitivity for COVID-19, which could prove to be as effective as HRCT in excluding a COVID-19 lung infection.

Seroprevalence of SARS-CoV-2 antibodies among first-trimester pregnant women during the second wave of the pandemic in India

Objective: Data on the immune response to SARS-CoV-2 during pregnancy are lacking and the potential role and effect of SARS-CoV-2 vaccination in pregnancy is yet to be completely investigated. Method: This is a cross-sectional observational study wherein pregnant women were tested for SARS-CoV-2 immunoglobulin M and immunoglobulin G levels, irrespective of their infective status or presence or symptomatology. Result: Of the 220 pregnant women tested, 160 (72.7%) were SARS-CoV-2 IgG positive, 37 (16.8%) were SARS-CoV-2 IgM positive and 27 (16.9%) were both IgG and IgM positive. The average antibody titer found was 10.49 BAU/ml (±14.0) and 0.6 (±0.55) for anti-SARS-CoV-2 IgG and IgM non neutralizing antibodies respectively. ROC analysis for SARS-CoV-2 IgG positivity showed a cut-off value of 1.19 with a sensitivity of 99.3% (0.99 AUC, 95% CI) and specificity of 98.3% (0.99 AUC, 95% CI), respectively. Similarly, ROC analysis for SARS-CoV-2 IgM positivity showed a cut-off value of 1 with a sensitivity of 97.3% (0.99 AUC, 95% CI) and specificity of 98.9% (0.99 AUC, 95% CI), respectively. Conclusion: First trimester sero-molecular screening suggests a high prevalence of COVID antibodies in the study population of pregnant women in the first trimester, without the patients being symptomatic. © 2022 International Federation of Gynecology and Obstetrics.