Timing and Depth Selection for Sedated Gastroscopy After SARS-CoV-2 Infection—A Retrospective Cohort Study (preprint)

Background Sedated gastroscopy is a crucial procedure for patients with upper respiratory infections. SARS-CoV-2-infected patients are more susceptible to anesthesia-related complications, such as edema, pharyngeal mucosa congestion, laryngospasm, and pulmonary infections.Methods We retrospectively analyzed a total of 386 patients who underwent sedated gastroscopy at the Affiliated Hospital of Qingdao University during the SARS-CoV-2 infection period. The patients were divided into three groups based on SARS-CoV-2 status: Negative (N), Two-week post-SARS-CoV-2 infection (T), and Three-week post-SARS-CoV-2 infection (Th) groups. Based on the anesthesia method, patients were divided into mild/moderate sedation and deep sedation/general anesthesia groups. Additionally, patients were categorized into groups based on COVID-19 severity and vaccination status. We recorded the laryngeal mucosal conditions, the occurrence rates of adverse reactions such as coughing, laryngospasm, and transient oxygen desaturation during the examination, as well as the satisfaction of patients and endoscopists were recorded.Results The T group displayed a significantly higher occurrence rate of adverse reactions when compared to the N and Th group, with decreased satisfaction levels of patients and endoscopists. In the T group, the occurrence rate of adverse reactions was higher in mild to moderate sedation than in deep sedation/general anesthesia methods, while patient and endoscopist satisfaction was lower. In the Th group, there was no statistically significant difference in the examination success rate or patient satisfaction between the mild/moderate sedation and deep sedation/general anesthesia methods; however, endoscopist satisfaction was lower with mild/moderate sedation method than deep sedation/general anesthesia method. There was a significant difference in the gastroscopy success rates of patients with different COVID-19 classifications. A significant difference was observed in the gastroscopy success rates among patients with different vaccination statuses.Conclusions Sedated gastroscopy post-three weeks of SARS-CoV-2 infection is safe. Moreover, using a deep sedation/general anesthesia method for sedated gastroscopy in SARS-CoV-2-infected patients within three weeks is significantly safer.

Investigation of Health-Related Quality of Life, Anxiety and Satisfaction in Patients with Pulmonary Embolism during the COVID-19 Pandemic (preprint)

Background: Features of post-traumatic stress disorder and anxiety may be present in Pulmonary Embolism (PE) patients along with impaired Quality of Life (QoL). We aim to evaluate health related QoL, anxiety and satisfaction with life, during the pandemic, in patients with a PE. Methods: Patients with PE were enrolled during their follow-up. All participants completed the Short Form 36 (SF-36) questionnaire, the State Trait Anxiety Inventory (STAI) X1 and X2 form, and the Satisfaction with Life Scale (SWLS). Results: 92 PE patients were included (mean age±SD=62.50±15.33 years, 56.5% males). Most of the mean values of the SF36 subscales were above the normative value except for “physical role functioning”) (45.92±42.41). “Emotional role functioning” (51.26±43.31) and “general health perceptions” (GH) (54.02±18.79) were slightly above the normative value of 50. Mean STAIX1 levels were 37.05±11.17 and mean STAIX2 levels were 39.80±10.47. Mean SWLS levels were 23.31±6.58. According to multiple linear regression analysis, mental healthscore (MH) and GH were predictive of SWLS(F (10,76) = 10.576, p

Modelling long COVID using Bayesian networks (preprint)

Motivated by the ambiguity of operational case definitions for long COVID and the impact of the lack of a common causal language on long COVID research, in early 2023 we began developing a research framework on this post-acute infection syndrome. We used directed acyclic graphs (DAGs) and Bayesian networks (BNs) to depict the hypothesised mechanisms of long COVID in an agnostic fashion. The DAGs were informed by the evolving literature and subsequently refined following elicitation workshops with domain experts. The workshops were structured online sessions guided by an experienced facilitator. The causal DAG aims to summarise the hypothesised pathobiological pathways from mild or severe COVID-19 disease to the development of pulmonary symptoms and fatigue over four different time points. The DAG was converted into a BN using qualitative parametrisation. These causal models aim to assist the identification of disease endotypes, as well as the design of randomised controlled trials and observational studies. The framework can also be extended to a range of other post-acute infection syndromes.

Risk of Adverse Events Following Monovalent Third or Booster Dose of COVID-19 mRNA Vaccination in U.S. Adults Ages 18 Years and Older (preprint)

Background: The U.S. FDA authorized the monovalent third primary series or booster doses of COVID-19 mRNA vaccines in August 2021 for persons 18 years and older. Monitoring of outcomes following updated authorizations is critical to evaluate vaccine safety and can provide early detection of rare adverse events (AEs) not identified in pre-licensure trials. Methods We evaluated the risk of 17 AEs following third doses of COVID-19 mRNA vaccines from August 2021 through early 2022 among adults aged 18-64 years in three commercial databases (Optum, Carelon Research, CVS Health) and adults aged >65 years in Medicare Fee-For-Service. We compared observed AE incidence rates to historical (expected) rates prior to the pandemic, estimated incidence rate ratios (IRRs) for the Medicare database and pooled IRR across the three commercial databases. Analyses were also stratified by prior history of COVID-19 diagnosis. Estimates exceeding a pre-defined threshold were considered statistical signals. Results Four AEs met the threshold for statistical signals for BNT162b2 and mRNA-1273 vaccines including Bells Palsy and pulmonary embolism in Medicare, and anaphylaxis and myocarditis/pericarditis in commercial databases. Nine AEs and three AEs signaled among adults with and without prior COVID-19 diagnosis, respectively. Conclusions This early monitoring study identified statistical signals for AEs following third doses of COVID-19 mRNA vaccination. Since this method is intended for screening purposes and generates crude results, results do not establish a causal association between the vaccines and AEs. FDAs public health assessment remains consistent that the benefits of COVID-19 vaccination outweigh the risks of vaccination.

Neuroleptic malignant syndrome in a patient with COVID-19 and the possible role of SARS-CoV-2 in its manifestation. Case report and overview of published cases (preprint)

Background: The manifestationof severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is more complex than that of pulmonary infection, and neuropsychiatric symptoms play a role in this complexity. In this paper, we present the case of a 29-year-old schizophrenic patient who suffered from neuroleptic malignant syndrome (NMS) that developed during coronavirus disease 2019 (COVID-19) infection, with an emphasis on the possible connection between these two conditions. Additionally, we provide an overview of published NMS cases in patients with COVID-19 or after vaccination against SARS-CoV-2. Case presentation: A 29-year-old patient treated for schizophrenia was admitted to the hospital for agitation and aggressivity; shortly after arrival at the hospital, laryngospasm and hypoxia occurred. The patient tested positive for SARS-CoV-2, and later, he developed pneumonia. After continuing restlessness, haloperidol was administered, and a few days later, neuroleptic malignant syndrome occurred. He was treated with bromocriptine and recovered. Conclusions: As SARS-CoV-2 is known to interact with angiotensin-converting enzyme 2 and DOPA-decarboxylase is known to be coexpressed with this receptor, we hypothesized that COVID-19 infection might playa substantial role in the development of NMS.

Delayed Fatal Pulmonary Hemorrhage Following COVID-19 Vaccination: Case Report, Batch Analysis, And Proposed Autopsy Checklist (preprint)

We present a case of a 47-year-old male who died unexpectedly from acute pulmonary hemorrhage 555 days after completing the BNT162b2 (Pfizer) COVID-19 vaccination primary series. Before death, he exhibited symptoms of a mild respiratory infection. Despite a healthy medical history and no medication use, the patient’s condition rapidly deteriorated and he experienced severe respiratory distress, followed by cardiopulmonary arrest with evidence of profuse pulmonary bleeding. Autopsy findings revealed massive lung congestion without embolism, normal heart size, moderate coronary atherosclerosis without myocardial infarction, and no evidence of other hemorrhagic events. The patient tested negative for COVID-19 and other respiratory pathogens at autopsy. Despite these findings, the medical examiner determined the cause of death was attributed to atherosclerotic and hypertensive cardiovascular disease, without considering the recent pulmonary hemorrhage and unremarkable medical history. Investigation into the vaccine batch indicated a higher-than-average number of serious adverse events, including fatalities. The patient's BNT162b2 batch was among the top 2.8% for reported deaths. Moreover, the autopsy failed to investigate potential contributions from the vaccine, such as the presence of the Spike protein or related antibodies. The evidence suggests that the pulmonary hemorrhage, exacerbated by a viral infection, was the immediate cause of death, with the COVID-19 vaccine potentially playing a role in the development of cardiopulmonary pathology and hemorrhage. We propose autopsy protocols for COVID-19 vaccine recipients to better investigate vaccine-related pathologies among those with one or more prior injections.

Evaluation of diseases complicating long COVID: A retrospective chart review (preprint)

Purpose Evidence for the pathogenesis and treatment of post-acute coronavirus disease 2019 (COVID-19) (long COVID) is lacking. As long COVID symptoms are predicted to have an impact on the global economy, clarification of the pathogenesis is urgently needed. Our experiences indicated that some symptoms were complicated by diseases established before the COVID-19 pandemic.Methods Using a retrospective, cross-sectional study, we aimed to evaluate the diseases complicating long COVID. Using the medical records of patients with confirmed severe acute respiratory syndrome coronavirus 2 infection exhibiting residual symptoms lasting ≥ 60 days post-infection who visited our clinic in January 2021–February 2023, we investigated the symptoms and diseases observed. We identified diseases that occurred after COVID-19 infection and excluded those that were exacerbations of existing diseases. Results: During the first visit, the most common symptoms reported in a total of 798 patients were fatigue (523 patients), anxiety (349 patients), and lack of motivation (344 patients). Complicating diseases were observed in 452 patients (57%). There were 115, 65, and 60 patients with postural tachycardia syndrome, postural syndrome without tachycardia, and mood disorders, respectively. Some diseases requiring immediate treatment included pulmonary thromboembolism, purulent shoulder arthritis, cerebellopontine angle tumors, myasthenia gravis, and cervical myelopathy.Conclusion All symptoms that occur after COVID-19 infection should not be treated as long COVID. Similar to normal medical treatment, a list of differential diagnoses should be maintained based on symptoms to obtain definitive diagnoses.

Long-term cardiovascular safety of COVID-19 vaccination according to brand, dose and combinations: Cohort study of 46 million adults in England (preprint)

Using longitudinal health records from 45.7 million adults in England followed for a year, our study compared the incidence of thrombotic and cardiovascular complications after first, second and booster doses of brands and combinations of COVID-19 vaccines used during the first two years of the UK vaccination program with the incidence before or without the corresponding vaccination. The incidence of common arterial thrombotic events (mainly acute myocardial infarction and ischaemic stroke) was generally lower after each vaccine dose, brand and combination. Similarly, the incidence of common venous thrombotic events, (mainly pulmonary embolism and lower limb deep venous thrombosis) was lower after vaccination. There was a higher incidence of previously reported rare harms after vaccination: vaccine-induced thrombotic thrombocytopenia after first ChAdOx1 vaccination, and myocarditis and pericarditis after first, second and transiently after booster mRNA vaccination (BNT-162b2 and mRNA- 1273) These findings support the wide uptake of future COVID-19 vaccination programs.

Clinical Characteristics and Outcomes of Children and Adolescents with cancer infected with SARS-CoV2 at a Tertiary Care Medical Center in Jordan. (preprint)

Background: Our knowledge about SARS-CoV2 infection is still evolving, its effects and complications on children and adolescents with cancer need to be studied more. The aim of this study is to present our experience with SARS-CoV2 infection in this population and to highlight specific complications and outcomes. Methods: This is a retrospective and prospective observational study, involved 21 cancer patients below the age of 18 years in north Jordan. Data regarding age, sex, cancer type, phase of treatment, duration between infection and chemotherapy and others were collected and reviewed. Results: A total of 21 patients with malignancy were included. Mean age of 8.5 years. Two patients (9.5%) had died; 4.7% is COVID related mortality and 4.7% related to cancer progression. Four patients had disease progression following SARS-CoV2 infection. Six cases developed hematological malignancy weeks to months after SARS-CoV2 infection and one patient was diagnosed with malignancy concomitantly with COVID-19 infection. Out of 15 patients with pre-existing malignancy, 1 patient (7%) developed pulmonary embolism, 4 (27%) patients were diagnosed with pneumonia and one patient was diagnosed with pericarditis (7%), 2 (13%) patients were admitted to pediatric intensive care unit. Regarding oxygen requirements; a total of 3 (20%) patients required some form of Oxygen supplementation. Conclusion: Diagnosis of COVID19 should not distract physicians from investigating new malignancy or relapse as they may come together or may be the result of COVID-19 infection. More studies and investigations are needed to identify the contribution of corona virus in pathogenesis of cancer.

Acute and absolute right ventricular systolic function improvement after large load of thrombi-in-transit solved by percutaneous interventionism in a patient with SARS-CoV2 pulmonary sequelae. (preprint)

Chronic complications of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2) are yet being investigated. We present a case of a patient with a bulla in the right lung as a SARS-CoV2 complication prompting segmentectomy. After surgery, and despite thromboprophylaxis, patient developed acute massive pulmonary embolism documented by point of care ultrasound. Our case highlights that in these patients, early diagnosis and treatment by percutaneous interventionism can alleviate volume and pressure overload and help in an overall improvement in right ventricular function.

The Diagnostic And Therapeutic Value Of Bronchoscopy In COVID-19 Patients On Veno-venous Extracorporeal Membrane Oxygenator (ECMO) Support: A Single Center Experience. (preprint)

Introduction: Mechanically ventilated patients COVID-19 patients on veno-venous extracorporeal membrane oxygenation (VV-ECMO) support often require bronchoscopy for pulmonary toilet. However, bronchoscopy in these patients may lead to tracheobronchial bleeding from instrumentation and vial aerosolization. The aim of this study was to assess the indications, benefits, and complications of bronchoscopy in critically ill patients with COVID-19 on VV-ECMO. Methods: This was a single center observational cohort study comprising of adults with COVID-19 infection that required mechanical ventilation and VV-ECMO from January 1, 2019 to November 1, 2021 and needed bronchoscopy. The primary outcome was improvement in patient outcome defined as either in improvement in PaO2 levels or VV-ECMO parameters 6 hours after the procedure. Secondary outcomes included microbiological data from the BAL samples. Mann-Whitney U and χ2 tests were used to compare continuous and categorical variables, respectively. Wilcoxon rank sum test for comparing correlated non-parametric continuous data. The median difference was calculated using the Hodges-Lehman estimator. Results: A total of 89 bronchoscopies were performed in 44 patients with COVID-19 on VV-ECMO. Median (IQR) PaO2 was 64 (57-75) mmHg prior to bronchoscopy, whereas it was mildly improved to 70 (58-89) mmHg, 6 hours after the procedure [Hodges-Lehman median difference (95% CI): 4.5 (2.0 – 8.0) mm Hg, p <0.01]. There was no significant difference in VV-ECMO parameters before and after the procedure. 10 patients had different microorganisms in broncheo-alveolar lavage that were not diagnosed with tracheal aspirate. No patient developed new bleeding post bronchoscopy requiring interruption of anticoagulation. No proceduralist reported testing positive for COVID-19 up to 2 weeks post bronchoscopy. Conclusions: Bronchoscopy is a feasible and relatively safe procedure in COVID-19 patients on VV-ECMO and might be beneficial in select patients to improve oxygenation and tailor antibiotic therapy. Larger studies are required to evaluate the overall impact on patient’s recovery with serial bronchoscopies.

The Prevalence of Previous Coronavirus Disease-19 as a Predisposing Factor in Pulmonary Thromboembolism and its Effect on Embolism Severity: A Multicenter, Observational, Cross-Sectional Study (preprint)

Background Knowledge of predisposing factors in developing pulmonary thromboembolism (PTE) is important in the diagnosis and treatment approach. The association between past coronavirus disease-19 (COVID-19) infection and PTE is a potential research topic. In this study we aimed to determine the prevalence of previous COVID-19 in addition to all predisposing factors for PTE development and to determine whether there is a difference in embolism severity in these cases.Methods Study design: Multicenter, observational, cross-sectional. Patients diagnosed with PTE between March 11, 2022, and March 11, 2023, were prospectively included in the study. Group 1: PTE cases with previous COVID-19, Group 2: PTE cases without previous COVID-19. To compare the categorical variables between groups the chi-square test was used. For continuous variables, parametric and non-parametric tests were used. Multivariate binary logistic regression analysis was performed to determine the independent variables related to PTE severity that affected the presence of previous COVID-19.Results Forty-four researchers from 33 centers participated in our study. A total of 1185 patients were included (Group 1; n = 360, Group 2; n = 825). The median post-COVID duration was 120.0 (min-max: 30–980) days. Computed tomography pulmonary angiography (CTPA) right ventricle/left ventricle (RV/LV) ratio > 1 was significantly higher in Group 2 compared to Group 1 (27.9% vs 19.7%, p = 0.003).The proportion of patients receiving systemic thrombolytic drugs (11.3% vs. 7.5%, p = 0.048), and the rate of patients who started treatment in the intensive care unit was higher in Group 2 (23.4% vs. 14.7%, p = 0.001). In multivariate logistic regression analysis, the absence of any identifiable risk factor for PTE was found to be a 0.46-fold protective factor in the presence of previous COVID-19 (95% CI: 0.274–0.760, p = 0.003) and an RV/LV ratio > 1 on CTPA was found to be a 0.60-fold protective factor (95% CI: 0.365–0.998, p = 0.049).Conclusions The prevalence of previous COVID-19 infection in PTE cases was 30.4%, and 26% of idiopathic cases had previous COVID-19 infection. Although the parameters related to embolism severity were higher in the non-COVID-19 group, in multivariate analyses, only idiopathic status was associated with a 2.2-fold increased risk in non-COVID-19 patients compared to those who had, and an RV/LV ratio > 1 on CTPA was associated with a 1.7-fold increased risk.

Thrombotic microangiopathy with kidney involvement in a patient with coronavirus disease 2019: A case report and literature review (preprint)

Background and aim: Millions of people worldwide have suffered from coronavirus disease 2019 (COVID-19). COVID-19 can lead to coagulopathy and thrombosis, presenting as pulmonary artery thromboembolism, deep vein thrombosis, and thrombotic microangiopathy (TMA), the latter being a rare finding in affected patients’ kidneys. Prior reports have rarely addressed the pathophysiology, clinical presentations, and therapeutic options in patients with COVID-19-associated TMA. Case presentation: We herein described a case of renal biopsy-proven TMA after COVID-19 in a 36-year-old woman. Initial examination revealed inflammation, acute kidney injury (AKI), anemia, and thrombocytopenia. She was diagnosed with hemolytic uremic syndrome, pulmonary infection, and COVID-19. After treatment, her condition stabilized but remained hemodialysis-dependent after discharge. One week later, she was re-hospitalized, and physical examination showed anemia and bilateral lower extremity edema. Abdominal ultrasound showed increased bilateral kidney echogenicity. Whole-exome sequencing detected an unknown variant of the C3 gene associated with hemolytic uremic syndrome susceptibility type 5/complement C3 deficiency. Kidney biopsy showed renal artery lesions, including small arteriole endothelial swelling, intimal thickening, mucinous degeneration, luminal occlusion, and small arterial wall necrosis. She received plasma exchange and steroids with significant renal function recovery. Conclusion: TMA likely contributed to AKI after COVID-19,thus supporting the notion that TMA plays an important role in the pathogenesis of COVID-19-related kidney injury. When diagnosing and treating COVID-19 patients with abnormal renal function, clinicians should incorporate kidney biopsy and genetic testing for the complement system, identify renal-limited and systemic TMA, and treat accordingly, which can improve patient outcomes.

Innate Immune Activation and Mitochondrial ROS Invoke Persistent Cardiac Conduction System Dysfunction after COVID-19 (preprint)

BackgroundCardiac risk rises during acute SARS-CoV-2 infection and in long COVID syndrome in humans, but the mechanisms behind COVID-19-linked arrhythmias are unknown. This study explores the acute and long term effects of SARS-CoV-2 on the cardiac conduction system (CCS) in a hamster model of COVID-19. MethodsRadiotelemetry in conscious animals was used to non-invasively record electrocardiograms and subpleural pressures after intranasal SARS-CoV-2 infection. Cardiac cytokines, interferon-stimulated gene expression, and macrophage infiltration of the CCS, were assessed at 4 days and 4 weeks post-infection. A double-stranded RNA mimetic, polyinosinic:polycytidylic acid (PIC), was used in vivo and in vitro to activate viral pattern recognition receptors in the absence of SARS-CoV-2 infection. ResultsCOVID-19 induced pronounced tachypnea and severe cardiac conduction system (CCS) dysfunction, spanning from bradycardia to persistent atrioventricular block, although no viral protein expression was detected in the heart. Arrhythmias developed rapidly, partially reversed, and then redeveloped after the pulmonary infection was resolved, indicating persistent CCS injury. Increased cardiac cytokines, interferon-stimulated gene expression, and macrophage remodeling in the CCS accompanied the electrophysiological abnormalities. Interestingly, the arrhythmia phenotype was reproduced by cardiac injection of PIC in the absence of virus, indicating that innate immune activation was sufficient to drive the response. PIC also strongly induced cytokine secretion and robust interferon signaling in hearts, human iPSC-derived cardiomyocytes (hiPSC-CMs), and engineered heart tissues, accompanied by alterations in electrical and Ca2+ handling properties. Importantly, the pulmonary and cardiac effects of COVID-19 were blunted by in vivo inhibition of JAK/STAT signaling or by a mitochondrially-targeted antioxidant. ConclusionsThe findings indicate that long term dysfunction and immune cell remodeling of the CCS is induced by COVID-19, arising indirectly from oxidative stress and excessive activation of cardiac innate immune responses during infection, with implications for long COVID Syndrome.

Th2 and Th17-Associated Immunopathology Following SARS-CoV-2 Breakthrough Infection in Spike-vaccinated ACE2-humanized Mice (preprint)

Vaccines have demonstrated remarkable effectiveness in protecting against COVID-19; however, concerns regarding vaccine-associated enhanced respiratory diseases (VAERD) following breakthrough infections have emerged. Spike protein subunit vaccines for SARS-CoV-2 induce VAERD in hamsters, where aluminum adjuvants promote a Th2-biased immune response, leading to increased type 2 pulmonary inflammation in animals with breakthrough infections. To gain a deeper understanding of the potential risks and the underlying mechanisms of VAERD, we immunized ACE2-humanized mice with SARS-CoV-2 Spike protein adjuvanted with aluminum and CpG-ODN. Subsequently, we exposed them to increasing doses of SARS-CoV-2 to establish a breakthrough infection. The vaccine elicited robust neutralizing antibody responses, reduced viral titers, and enhanced host survival. However, following a breakthrough infection, vaccinated animals exhibited severe pulmonary immunopathology, characterized by a significant perivascular infiltration of eosinophils and CD4+ T cells, along with increased expression of Th2/Th17 cytokines. Intracellular flow cytometric analysis revealed a systemic Th17 inflammatory response, particularly pronounced in the lungs. Our data demonstrate that aluminum/CpG adjuvants induce strong antibody and Th1-associated immunity against COVID-19 but also prime a robust Th2/Th17 inflammatory response, which may contribute to the rapid onset of T cell-mediated pulmonary immunopathology following a breakthrough infection. These findings underscore the necessity for further research to unravel the complexities of VAERD in COVID-19 and to enhance vaccine formulations for broad protection and maximum safety.

Single-cell RNA sequencing reveals characteristics of myeloid cells in pulmonary post-acute sequelae of SARS-CoV-2 (preprint)

Background: Although our understanding of the immunopathology and subsequent risk and severity of COVID-19 disease is evolving, a detailed account of immune responses that contribute to the long-term consequences of pulmonary complication in COVID-19 infection remain unclear. Few studies have detailed the immune and cytokine profiles associated with post-acute sequelae of SARS-CoV-2 infection with persistent pulmonary symptoms (PPASC). However, the dysregulation of the immune system that drives pulmonary sequelae in COVID-19 survivors and PASC sufferers remains largely unknown. Results: To characterize the immunological features of pulmonary PASC (PPASC), we performed droplet-based single-cell RNA sequencing to study the transcriptomic profiles of peripheral blood mononuclear cells (PBMCs) from participants naive to SARS-CoV-2 (Control) and infected with SARS-CoV-2 with chronic pulmonary symptoms (PPASC). We analyzed more than 34,139 PBMCs by integrating our dataset with previously reported control datasets (GSM4509024) cell distribution. In total, 11 distinct cell populations were identified based on the expression of canonical markers. The proportion of myeloid-lineage cells ([MLCs]; CD14+/CD16+monocytes and dendritic cells) was increased in PPASC compared to controls. MLCs from PPASC displayed up-regulation of genes associated with pulmonary symptoms/fibrosis, while glycolysis metabolism-related genes were downregulated. Similarly, pathway analysis showed that fibrosis-related (VEGF, WNT, and SMAD) and cell death pathways were up-regulated, but immune pathways were down-regulated in PPASC. In PPASC, we observed interactive VEGF ligand-receptor pairs among MLCs, and network modules in CD14+ (cluster 4) and CD16+ (Cluster 5) monocytes displayed a significant enrichment for biological pathways linked to adverse COVID-19 outcomes, fibrosis, and angiogenesis. Further analysis revealed a distinct metabolic alteration in MLCs with a down-regulation of glycolysis/gluconeogenesis in PPASC compared to SARS-CoV-2 naive samples. Conclusion: This study offers valuable insights into the immune response and cellular landscape in PPASC. The presence of elevated MLC levels and their corresponding gene signatures associated with fibrosis, immune response suppression, and altered metabolic states suggests their potential role as a driver of PPASC.

Epigenetic liquid biopsies reveal elevated vascular endothelial cell turnover and erythropoiesis in asymptomatic COVID-19 patients (preprint)

The full spectrum of tissues affected by SARS-CoV-2 infection is crucial for deciphering the heterogenous clinical course of COVID-19. Here, we analyzed DNA methylation and histone modification patterns in circulating chromatin to assess cell type-specific turnover in severe and asymptomatic COVID-19 patients, in relation to clinical outcome. Patients with severe COVID-19 had a massive elevation of circulating cell-free DNA (cfDNA) levels, which originated in lung epithelial cells, cardiomyocytes, vascular endothelial cells and erythroblasts, suggesting increased cell death or turnover in these tissues. The immune response to infection was reflected by elevated B cell and monocyte/macrophage cfDNA levels, and by evidence of an interferon response in cells prior to cfDNA release. Strikingly, monocyte/macrophage cfDNA levels (but not monocyte counts), as well as lung epithelium cfDNA and vascular endothelial cfDNA, predicted clinical deterioration and duration of hospitalization. Asymptomatic patients had elevated levels of immune-derived cfDNA but did not show evidence of pulmonary or cardiac damage. Surprisingly, these patients showed elevated levels of vascular endothelial cell and erythroblast cfDNA, suggesting that sub-clinical vascular and erythrocyte turnover are universal features of COVID-19, independent of disease severity. Epigenetic liquid biopsies provide non-invasive means of monitoring COVID-19 patients, and reveal sub-clinical vascular damage and red blood cell turnover.

Serum VEGF Levels on Admission in COVID-19 Patients Correlate with SP-D and Neutrophils, Reflecting Disease Severity: A Prospective Study (preprint)

Background and objective: The COVID-19 pandemic caused by SARS-CoV-2 has resulted in significant global morbidity and mortality. This study aimed to investigate the clinical significance of serum vascular endothelial growth factor (VEGF) in COVID-19 patients and its association with disease severity and pulmonary injury. Methods: We prospectively collected data from 71 hospitalized COVID-19 patients between June 2020 and January 2021. Patients were classified as either mild or severe based on their oxygen requirements during hospitalization. Serum VEGF levels were measured using an ELISA kit. Results: In comparison to mild cases, significantly elevated serum VEGF levels were observed in severe COVID-19 patients. Furthermore, VEGF levels exhibited a positive correlation with white blood cell count, neutrophil count, and lymphocyte count. Notably, serum surfactant protein-D (SP-D), an indicator of alveolar epithelial cell damage, was significantly higher in patients with elevated VEGF levels. Conclusion: These results suggest that elevated serum VEGF could levels serve as a prognostic biomarker for COVID-19 as it is indicative of alveolar epithelial cell injury caused by SARS-CoV-2 infection. Additionally, we observed a correlation between VEGF and neutrophil activation, which plays a role in the immune response during endothelial cell injury, indicating a potential involvement of angiogenesis in disease progression. Further research is needed to elucidate the underlying mechanisms of VEGF in COVID-19.

Myocardial Infarction, Deep Venous Thrombosis, and Pulmonary Embolism in SARs-CoV-2 Hospitalizations; Insights from the National Inpatient Sample 2020 (preprint)

Background: We studied the outcomes of SARS-CoV-2 (COVID) hospitalizations and their association with myocardial injury and thrombosis. Methods: Retrospective analysis of the National Inpatient Sample 2020 database. Results: We identified 335,799 hospitalizations with COVID. Of these, 1.6% (5,355) were diagnosed with non-ST-segment myocardial infarction (COVNSTEMI). The mean age of COVID hospitalizations was 71.7, with 60.50% being males. The population prevalence included 53.10% Whites, 17.80% Blacks, 19.20% Hispanics, and 4.10% Asians. The average length of stay (LOS) was 10 days, and 37.60% of patients died during their hospitalization. The average cost of hospitalization (TOTCHG) was $156,633. The COVSTEMI group comprised 1,364 cases, with a mean age of 67.4, in-hospital mortality of 47.4%, and the mean TOTCHG was $177,600. The DVTCOV group comprised 2,869 cases, while the PECOV group had 4,828 cases. Male predominance was observed in both groups, with mean ages of 66 years in the DVTCOV group and 64 years in the PECOV group. The DVTCOV group had a LOS of 16 days, with 24.71% mortality, while the PECOV group had a LOS of 11 days, with 19.20% mortality. The average TOTCHG in the DVTCOV group was $248,900, whereas it was $145,378 in the PECOV group. Conclusion: Our study revealed significant mortality rates across different groups, including 38% in COVNSTEMI, 47% in COVSTEMI, 25% in DVTCOV, and 19% in PECOV. These findings highlight the severity of COVID-related complications and the substantial financial burden of hospitalization.