Diagnostic sensitivity of RT-PCR assays on nasopharyngeal specimens for detection of SARS-CoV-2 infection: A Systematic Review and Meta-Analysis.

Background: Reverse transcription polymerase chain reaction (RT-PCR) is the current standard of reference in the diagnosis of SARS-CoV-2 infection. In outpatient clinical practice, nasopharyngeal swab RT-PCR testing is still the most common procedure. The purpose of this systematic review and meta-analysis was to evaluate the sensitivity of RT-PCR nasopharyngeal assays. Methods: We searched three databases, including PubMed/MEDLINE, EMBASE, and Cochrane Library, using a comprehensive strategy. Studies investigating the sensitivity of SARS-CoV-2 RT-PCR nasopharyngeal assays in adults were included. Two reviewers extracted data and assessed trial quality independently. Pooled sensitivity and its confidence interval were computed using the meta package in R. Results: Thirteen studies were found eligible for the inclusion in the systematic review. Out of these, 25 different sub-studies were identified and included in the meta-analysis, which reported the sensitivities of 25 different nasopharyngeal RT-PCR assays. Finally, the overall pooled sensitivity resulted 89% (95% CI, 85.4 to 91.8%). Conclusion: Our study suggests that RT-PCR assays on nasopharyngeal specimens have a substantial sensitivity for diagnosing SARS-CoV-2 infection.

Risk stratification of patients with SARS-CoV-2 by tissue factor expression in circulating extracellular vesicles.

Inflammatory response following SARS-CoV-2 infection results in substantial increase of amounts of intravascular pro-coagulant extracellular vesicles (EVs) expressing tissue factor (CD142) on their surface. CD142-EV turned out to be useful as diagnostic biomarker in COVID-19 patients. Here we aimed at studying the prognostic capacity of CD142-EV in SARS-CoV-2 infection. Expression of CD142-EV was evaluated in 261 subjects admitted to hospital for pneumonia and with a positive molecular test for SARS-CoV-2. The study population consisted of a discovery cohort of selected patients (n = 60) and an independent validation cohort including unselected consecutive enrolled patients (n = 201). CD142-EV levels were correlated with post-hospitalization course of the disease and compared to the clinically available 4C Mortality Score as referral. CD142-EV showed a reliable performance to predict patient prognosis in the discovery cohort (AUC = 0.906) with an accuracy of 81.7%, that was confirmed in the validation cohort (AUC = 0.736). Kaplan-Meier curves highlighted a high discrimination power in unselected subjects with CD142-EV being able to stratify the majority of patients according to their prognosis. We obtained a comparable accuracy, being not inferior in terms of prediction of patients' prognosis and risk of mortality, with 4C Mortality Score. The expression of surface vesicular CD142 and its reliability as prognostic marker was technically validated using different immunocapture strategies and assays. The detection of CD142 on EV surface gains considerable interest as risk stratification tool to support clinical decision making in COVID-19.

1-year radiological, functional and quality-of-life outcomes in patients with SARS-CoV-2 pneumonia - A prospective observational study.

All over the world, SARS-CoV-2 pneumonia is causing a significant short and medium-term morbidity and mortality, with reported persisting symptoms, radiological and lung alterations up to 6 months after symptoms onset. Nevertheless, the 1-year impact on affected patients is still poorly known. In this prospective observational study, 39 patients with SARS-CoV-2 pneumonia were recruited from a single COVID-19 hospital in Southern Switzerland. They underwent a 3-month and 1-year follow-ups. At 1 year, 38 patients underwent functional follow-up through lung function tests and six minutes walking test and submitted SF-12 and SGRQ questionnaires about health-related quality of life. At 1 year most of the patients showed a persistence of the radiological and functional abnormalities and a reduction of the health-related quality of life. Thirty patients (96.8%) still presented some residual abnormalities on CT scans (31 patients at 3 months), though with a general reduction of the lesional load in all lung lobes. Twenty patients (52.6%) had persisting lung function tests impairment, with an overall improvement of DLCO. As concerning the functional status, lowest SpO2 during 6MWT increased significantly. Finally, 19 patients (50%) reported a pathological St. George's Respiratory Questionnaire, and respectively 12 (31.6%) and 11 (28.9%) patients a pathological Short Form Survey-12 in physical and mental components. At 1-year follow-up SARS-CoV-2 pneumonia survivors still present a substantial impairment in radiological and functional findings and in health-related quality of life, despite showing a progressive recovery.

Clinical, radiological and functional outcomes in patients with SARS-CoV-2 pneumonia: a prospective observational study.

BACKGROUND: All over the world, SARS-CoV-2 pneumonia is causing a significant short-term morbidity and mortality, but the medium-term impact on lung function and quality of life of affected patients are still unknown. METHODS: In this prospective observational study, 39 patients with SARS-CoV-2 pneumonia were recruited from a single COVID-19 hospital in Southern Switzerland. At three months patients underwent radiological and functional follow-up through CT scan, lung function tests, and 6 min walking test. Furthermore, quality of life was assessed through self-reported questionnaires. RESULTS: Among 39 patients with SARS-CoV-2 pneumonia, 32 (82% of all participants) presented abnormalities in CT scan and 25 (64.1%) had lung function tests impairment at three months. Moreover, 31 patients (79.5%) reported a perception of poor health due to respiratory symptoms and all 39 patients showed an overall decreased quality of life. CONCLUSIONS: Medium-term follow up at three months of patients diagnosed with SARS-CoV-2 pneumonia shows the persistence of abnormalities in CT scans, a significant functional impairment assessed by lung function tests and a decreased quality of life in affected patients. Further studies evaluating the long-term impact are warranted to guarantee an appropriate follow-up to patients recovering from SARS-CoV-2 pneumonia.

Circulating extracellular vesicles are endowed with enhanced procoagulant activity in SARS-CoV-2 infection.

BACKGROUND: Coronavirus-2 (SARS-CoV-2) infection causes an acute respiratory syndrome accompanied by multi-organ damage that implicates a prothrombotic state leading to widespread microvascular clots. The causes of such coagulation abnormalities are unknown. The receptor tissue factor, also known as CD142, is often associated with cell-released extracellular vesicles (EV). In this study, we aimed to characterize surface antigens profile of circulating EV in COVID-19 patients and their potential implication as procoagulant agents. METHODS: We analyzed serum-derived EV from 67 participants who underwent nasopharyngeal swabs molecular test for suspected SARS-CoV-2 infection (34 positives and 33 negatives) and from 16 healthy controls (HC), as referral. A sub-analysis was performed on subjects who developed pneumonia (n = 28). Serum-derived EV were characterized for their surface antigen profile and tested for their procoagulant activity. A validation experiment was performed pre-treating EV with anti-CD142 antibody or with recombinant FVIIa. Serum TNF-α levels were measured by ELISA. FINDINGS: Profiling of EV antigens revealed a surface marker signature that defines circulating EV in COVID-19. A combination of seven surface molecules (CD49e, CD209, CD86, CD133/1, CD69, CD142, and CD20) clustered COVID (+) versus COVID (-) patients and HC. CD142 showed the highest discriminating performance at both multivariate models and ROC curve analysis. Noteworthy, we found that CD142 exposed onto surface of EV was biologically active. CD142 activity was higher in COVID (+) patients and correlated with TNF-α serum levels. INTERPRETATION: In SARS-CoV-2 infection the systemic inflammatory response results in cell-release of substantial amounts of procoagulant EV that may act as clotting initiation agents, contributing to disease severity. FUNDING: Cardiocentro Ticino Institute, Ente ospedaliero Cantonale, Lugano-Switzerland.

Conservative Management of COVID-19 Patients-Emergency Palliative Care in Action.

CONTEXT: The COVID-19 pandemic is spreading across the world. Many patients will not be suitable for mechanical ventilation owing to the underlying health conditions, and they will require a conservative approach including palliative care management for their important symptom burden. OBJECTIVES: To develop a management plan for patients who are not suitable for mechanical ventilation that is tailored to the stage their COVID-19 disease. METHODS: Patients were identified as being stable, unstable, or at the end of life using the early warning parameters for COVID-19. Furthermore, a COVID-19-specific assessment tool was developed locally, focusing on key symptoms observed in this population which assess dyspnoea, distress, and discomfort. This tool helped to guide the palliative care management as per patients' disease stage. RESULTS: A management plan for all patients' (stable, unstable, end of life) was created and implemented in acute hospitals. Medication guidelines were based on the limitations in resources and availability of drugs. Staff members who were unfamiliar with palliative care required simple, clear instructions to follow including medications for key symptoms such as dyspnoea, distress, fever, and discomfort. Nursing interventions and family involvement were adapted as per patients' disease stage and infection control requirements. CONCLUSION: Palliative care during the COVID-19 pandemic needs to adapt to an emergency style of palliative care as patients can deteriorate rapidly and require quick decisions and clear treatment plans. These need to be easily followed up by generalist staff members caring for these patients. Furthermore, palliative care should be at the forefront to help make the best decisions, give care to families, and offer spiritual support.