Coagulopathy in elderly patients with coronavirus disease 2019

Proteomic analysis of lung responses to SARS-CoV-2 infection in aged non-human primates: clinical and research relevance

With devastating health and socioeconomic impact worldwide, much work is left to understand the Coronavirus Disease 2019 (COVID-19), with emphasis in the severely affected elderly population. Here, we present a proteomics study of lung tissue obtained from aged vs. young rhesus macaques (Macaca mulatta) and olive baboons (Papio Anubis) infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Using age as a variable, we identified common proteomic profiles in the lungs of aged infected non-human primates (NHPs), including key regulators of immune function, as well as cell and tissue remodeling, and discuss the potential clinical relevance of such parameters. Further, we identified key differences in proteomic profiles between both NHP species, and compared those to what is known about SARS-CoV-2 in humans. Finally, we explored the translatability of these animal models in the context of aging and the human presentation of the COVID-19.

The Mysterious Risk of Arterial Thrombosis With COVID-19: A Case Series of Acute Limb Ischaemia in Vaccinated Patients

Introduction Coronavirus-19 (COVID-19) plays a vital role in viral-induced hypercoagulability through the initiation of a cytokine storm. This mechanism has been found to predispose unvaccinated patients to systemic complications including arterial thrombosis (AT) with poor 30-day amputation-free survival rates. There remains, however, little understanding regarding the incidence in patients who have received a COVID-19 vaccination. This study aims to assess the incidence, management and outcomes of vaccinated patients with COVID-19 who develop thrombotic complications to reduce amputation and direct mortality. Methods The case notes of all emergency patients with COVID-19 referred to the vascular services in a tertiary referral centre between November 2021 and April 2022 were reviewed. Patients who were unvaccinated or admitted with stroke or coronary thrombosis were excluded. The study was undertaken to measure 30-day outcomes. Results Between November 2021 and April 2022, 167,290 people tested positive for COVID-19 in Norfolk. Thirty-one patients under the vascular service had COVID-19, of which, one patient was unvaccinated. Only one vaccinated patient was referred with AT and had a positive COVID-19 result two days after admission. Above-knee amputation was performed within 30 days and he survived. Seventeen percent of patients contracted COVID-19 during their hospital admission. Conclusion The incidence of acute limb ischaemia in vaccinated patients is low; however, the 30-day outcomes remain poor. Compared to unvaccinated patients, there was a significant reduction in the presentation of AT in vaccinated patients during that timeframe, despite a higher background number of COVID-19 cases. Therefore, vaccination may minimise the risk of AT.

COVID-19 associated coagulopathy: A bibliometric investigation

Infection with SARS-CoV-2 initiates an immune-hemostatic response. While both systems are intimately connected and necessary for an efficient immune response to contain the infection, excessive coagulation activation might exceed the valuable benefits by causing thrombotic consequences and excessive inflammation. This biological response is new to clinicians and researchers, and accordingly, tremendous studies have been conducted on coagulopathy and its relationship to COVID-19 disease during this pandemic. Therefore, it takes a research insight from a bibliometric perspective to determine research hotspots and trends of COVID-19 associated coagulopathy (C19-CA). The analysis relies on the Scopus database for bibliographic content and Visualization of Similarities viewer software to map bibliometric data of C19-CA. Our study finds the most eminent authors, journals, institutions, funding organizations, and countries that publish in the C19-CA. Additionally; this research employs bibliometric analysis of co-authorship, co-citations, bibliographic coupling, and co-occurrence of keywords. A total of 2242 studies were retrieved, and the number of annual publications of C19-CA showed remarkable growth. The top-publishing authors on C19-CA are Smadja, D.M., Diehl, J.L., and Gendron, N (France). The total number of articles published in English in these three years was 1241, with the original article accounting for 99.8% and conference papers accounting for 0.2%. Huazhong University of Science and Technology (China) is the top-productive institution, with the US being the top-publishing country. Journal of Thrombosis and Thrombolysis received the highest number of original articles. The research results were mainly published in the fields of Medicine, Biochemistry, Genetics, and Molecular Biology, Immunology and Microbiology. Yuanyuan Li, who is (China), is the top-collaborating author. China and its authors have the highest number of citations. Keywords' co-occurrence analyses of the authors and all keywords revealed the following themes in C19-CA; abnormal coagulation parameters, pulmonary coagulopathy, venous and arterial thrombotic disorders, distinct features of coagulopathy, inflammation, and thrombosis in COVID-19, and anticoagulants and thrombolytic therapies. By combining bibliometric analysis with VOSviewer software, we identified C19-CA's leaders, collaborating institutions, and research hotspots, as well as give references for future research paths.

Approach to Thromboprophylaxis for Prevention of Venous Thromboembolism in COVID-19: Global Updates and Clinical Insights from India

Venous thromboembolism (VTE) frequently occurs in patients with coronavirus disease-19 (COVID-19) and is associated with increased mortality. Several global guidelines recommended prophylactic-intensity anticoagulation rather than intermediate-intensity or therapeutic-intensity anticoagulation for patients with COVID-19-related acute or critical illness without suspected or confirmed VTE. Even though standard doses of thromboprophylaxis are received, many cases of thrombotic complications are reported; hence, appropriate and adequate thromboprophylaxis is critical for the prevention of VTE in COVID-19. In spite of an increased prevalence of VTE in Indian patients, sufficient data on patient characteristics, diagnosis, and therapeutic approach for VTE in COVID is lacking. In this article, we review the available global literature (search conducted up to 31 May 2021) and provide clinical insights into our approach towards managing VTE in patients with COVID-19. Furthermore, in this review, we summarize the incidence and risk factors for VTE with emphasis on the thromboprophylaxis approach in hospitalized patients and special populations with COVID-19 and assess clinical implications in the Indian context.

Factors Modulating COVID-19: A Mechanistic Understanding Based on the Adverse Outcome Pathway Framework

Addressing factors modulating COVID-19 is crucial since abundant clinical evidence shows that outcomes are markedly heterogeneous between patients. This requires identifying the factors and understanding how they mechanistically influence COVID-19. Here, we describe how eleven selected factors (age, sex, genetic factors, lipid disorders, heart failure, gut dysbiosis, diet, vitamin D deficiency, air pollution and exposure to chemicals) influence COVID-19 by applying the Adverse Outcome Pathway (AOP), which is well-established in regulatory toxicology. This framework aims to model the sequence of events leading to an adverse health outcome. Several linear AOPs depicting pathways from the binding of the virus to ACE2 up to clinical outcomes observed in COVID-19 have been developed and integrated into a network offering a unique overview of the mechanisms underlying the disease. As SARS-CoV-2 infectibility and ACE2 activity are the major starting points and inflammatory response is central in the development of COVID-19, we evaluated how those eleven intrinsic and extrinsic factors modulate those processes impacting clinical outcomes. Applying this AOP-aligned approach enables the identification of current knowledge gaps orientating for further research and allows to propose biomarkers to identify of high-risk patients. This approach also facilitates expertise synergy from different disciplines to address public health issues.

Heparin for patients with coronavirus disease 2019 and hypercoagulation complications: A cohort study

Background

Thrombotic complications of coronavirus disease 2019 (COVID-19) are a worrisome aspect of the disease due to their high incidence in critically ill patients and their poor clinical outcomes. The aim of this study was to compare the effectiveness of unfractionated heparin (UFH) and low molecular weight heparin (LMWH) (fondaparinux) in hospitalized COVID-19 patients with hypercoagulable complications.

Material and methods

The study design used a retrospective cohort approach incorporating pre- and post-tests via secondary data extracted from the medical records of inpatients with confirmed COVID-19.

Results

Among the 98 individuals studied (52% women; 30.6% at >60 years of age), 35 patients received UFH, while the remaining 63 patients received LMWH (fondaparinux). The greatest decrease in the D-dimer value (0.01 ± 0.5 g fibrinogen equivalent units/mL) was observed in 12 (34.3%) and 15 (23.8%) patients in the UFH and LMWH (fondaparinux) groups, respectively. Most inpatients with confirmed COVID-19 were aged 50–59 years and were women.

Conclusion

There was a tendency toward increased D-dimer, normal prothrombin time, normal activated partial thromboplastin clotting time, and increased fibrinogen values in each COVID-19 patient. The results demonstrated a significant relationship between the D-dimer and prothrombin time parameter in confirmed COVID-19 inpatients.

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Most of the hospitalized patients with confirmed COVID-19 were >60-years of age and female.

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Patients in both treatment groups (UFH and LMWH (fondaparinux)) showed a significant decrease in D-dimer values.

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Both drugs have a similar effectiveness in the treatment of coagulopathy.

Elevated Levels of Pleiotropic Interleukin-6 (IL-6) and Interleukin-10 (IL-10) are Critically Involved With the Severity and Mortality of COVID-19: An Updated Longitudinal Meta-Analysis and Systematic Review on 147 Studies

Objectives

Disruption in the natural immune reaction due to SARS-CoV-2 infection can initiate a potent cytokine storm among COVID-19 patients. An elevated level of IL-6 and IL-10 during a hyperinflammatory state plays a vital role in increasing the risk of severity and mortality. In this study, we aimed to evaluate the potential of circulating IL-6 and IL-10 levels as biomarkers for detecting the severity and mortality of COVID-19.

Methods

This study was conducted according to the Cochrane Handbook and PRISMA guidelines. Authorized databases were searched to extract suitable studies using specific search terms. RevMan 5.4 was applied for performing the meta-analysis. Mean differences in IL-6 and IL-10 levels were calculated among COVID-19 patients via a random-effects model. NOS scoring, publication bias and sensitivity analyses were checked to ensure study quality.

Results

A total of 147 studies were selected, with 31 909 COVID-19 patients under investigation. In the severity analysis, the mean concentration of IL-6 was significantly higher in the severe COVID-19 cases than in the non-severe cases (MD: 19.98; P < .001; 95% CI: 17.56, 22.40). Similar result was observed for IL-10 mean concentration in severe COVID-19 cases (MD: 1.35; P < .001; 95% CI: 0.90, 1.80). In terms of mortality analysis, circulating IL-6 showed sharp elevation in the deceased patients (MD: 42.11; P < .001; 95% CI: 36.86, 47.36). IL-10 mean concentration was higher in the dead patients than in the survived patients (MD: 4.79; P < .001; 95% CI: 2.83, 6.75). Publication bias was not found except for comparing IL-6 levels with disease severity. Sensitivity analysis also reported no significant deviation from the pooled outcomes.

Conclusions

Elevated levels of circulating IL-6 and IL-10 signifies worsening of COVID-19. To monitor the progression of SARS-CoV-2 infection, IL-6 and IL-10 should be considered as potential biomarkers for severity and mortality detection in COVID-19.

Systematic review registration

INPLASY registration number: INPLASY202240046.

The mechanism underlying extrapulmonary complications of the coronavirus disease 2019 and its therapeutic implication

The coronavirus disease 2019 (COVID-19) is a highly transmissible disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that poses a major threat to global public health. Although COVID-19 primarily affects the respiratory system, causing severe pneumonia and acute respiratory distress syndrome in severe cases, it can also result in multiple extrapulmonary complications. The pathogenesis of extrapulmonary damage in patients with COVID-19 is probably multifactorial, involving both the direct effects of SARS-CoV-2 and the indirect mechanisms associated with the host inflammatory response. Recognition of features and pathogenesis of extrapulmonary complications has clinical implications for identifying disease progression and designing therapeutic strategies. This review provides an overview of the extrapulmonary complications of COVID-19 from immunological and pathophysiologic perspectives and focuses on the pathogenesis and potential therapeutic targets for the management of COVID-19.

Immune characterization of a Colombian family cluster with SARS-CoV-2 infection

Introduction:

Immunological markers have been described during COVID-19 and persist after recovery. These immune markers are associated with clinical features among SARS- CoV-2 infected individuals. Nevertheless, studies reporting a comprehensive analysis of the immune changes occurring during SARS-CoV-2 infection are still limited.

Objective:

To evaluate the production of proinflammatory cytokines, the antibody response, and the phenotype and function of NK cells and T cells in a Colombian family cluster with SARS-CoV-2 infection.

Materials and methods:

Proinflammatory cytokines were evaluated by RT-PCR and ELISA. The frequency, phenotype, and function of NK cells (cocultures with K562 cells) and T-cells (stimulated with spike/RdRp peptides) were assessed by flow cytometry. Anti-SARS-CoV-2 antibodies were determined using indirect immunofluorescence and plaque reduction neutralization assay.

Results:

During COVID-19, we observed a high proinflammatory-cytokine production and a reduced CD56^bright-NK cell and cytotoxic response. Compared with healthy controls, infected individuals had a higher frequency of dysfunctional CD8+ T cells CD38+HLA-DR-. During the acute phase, CD8+ T cells stimulated with viral peptides exhibited a monofunctional response characterized by high IL-10 production. However, during recovery, we observed a bifunctional response characterized by the co-expression of CD107a and granzyme B or perforin.

Conclusion:

Although the proinflammatory response is a hallmark of SARS-CoV-2 infection, other phenotypic and functional alterations in NK cells and CD8+ T cells could be associated with the outcome of COVID-19. However, additional studies are required to understand these alterations and to guide future immunotherapy strategies.

Serum Neurofilament Light is elevated in COVID-19 Positive Adults in the ICU and is associated with Co-Morbid Cardiovascular Disease, Neurological Complications, and Acuity of Illness

In critically ill COVID-19 patients, the risk of long-term neurological consequences is just beginning to be appreciated. While recent studies have identified that there is an increase in structural injury to the nervous system in critically ill COVID-19 patients, there is little known about the relationship of COVID-19 neurological damage to the systemic inflammatory diseases also observed in COVID-19 patients. The purpose of this pilot observational study was to examine the relationships between serum neurofilament light protein (NfL, a measure of neuronal injury) and co-morbid cardiovascular disease (CVD) and neurological complications in COVID-19 positive patients admitted to the intensive care unit (ICU). In this observational study of one-hundred patients who were admitted to the ICU in Tucson, Arizona between April and August 2020, 89 were positive for COVID-19 (COVID-pos) and 11 was COVID-negative (COVID-neg). A healthy control group (n=8) was examined for comparison. The primary outcomes and measures were subject demographics, serum NfL, presence and extent of CVD, diabetes, sequential organ failure assessment score (SOFA), presence of neurological complications, and blood chemistry panel data. COVID-pos patients in the ICU had significantly higher mean levels of Nfl (229.6 ± 163 pg/ml) compared to COVID-neg ICU patients (19.3 ± 5.6 pg/ml), Welch's t-test, p =.01 and healthy controls (12.3 ± 3.1 pg/ml), Welch's t-test p =.005. Levels of Nfl in COVID-pos ICU patients were significantly higher in patients with concomitant CVD and diabetes (n=35, log Nfl 1.6±.09), and correlated with higher SOFA scores (r=.5, p =.001). These findings suggest that in severe COVID-19 disease, the central neuronal and axonal damage in these patients may be driven, in part, by the level of systemic cardiovascular disease and peripheral inflammation. Understanding the contributions of systemic inflammatory disease to central neurological degeneration in these COVID-19 survivors will be important to the design of interventional therapies to prevent long-term neurological and cognitive dysfunction.

Could live attenuated vaccines better control COVID-19?

In an effort to control the COVID-19 pandemic, large-scale vaccination is being implemented in various countries using anti-SARS-CoV-2 vaccines based on mRNAs, adenovirus vectors, and inactivated viruses. However, there are concerns regarding adverse effects, such as the induction of fever attributed to mRNA vaccines and pre-existing immunity against adenovirus vectored vaccines or their possible involvement in the development of thrombosis. The induction of antibodies against the adenovirus vector itself constitutes another hindrance, rendering boosting vaccinations ineffective. Additionally, it has been questioned whether inactivated vaccines that predominantly induce humoral immunity are effective against newly arising variants, as some isolated strains were found to be resistant to the serum from COVID-19-recovered patients. Although the number of vaccinated people is steadily increasing on a global scale, it is still necessary to develop vaccines to address the difficulties and concerns mentioned above. Among the various vaccine modalities, live attenuated vaccines have been considered the most effective, since they closely replicate a natural infection without the burden of the disease. In our attempt to provide an additional option to the repertoire of COVID-19 vaccines, we succeeded in isolating temperature-sensitive strains with unique phenotypes that could serve as seeds for a live attenuated vaccine. In this review article, we summarize the characteristics of the currently approved SARS-CoV-2 vaccines and discuss their advantages and disadvantages. In particular, we focus on the novel temperature-sensitive variants of SARS-CoV-2 that we have recently isolated, and their potential application as live-attenuated vaccines. Based on a thorough evaluation of the different vaccine modalities, we argue that it is important to optimize usage not only based on efficacy, but also on the phases of the pandemic. Our findings can be used to inform vaccination practices and improve global recovery from the COVID-19 pandemic.

Aging & COVID-19 susceptibility, disease severity, and clinical outcomes: The role of entangled risk factors

The emergence of Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) in late 2019 has been associated with a high rate of mortality and morbidity. It has been determined that the old population are not only at an increased risk for affliction with COVID-19 infection, but also atypical presentations, severe forms of the disease, and mortality are more common in this population. A plethora of mechanisms and risk factors contribute to the higher risk of infection in the old population. For instance, aging is associated with an increment in the expression of Angiotensin-Converting Enzyme-2 (ACE-2), the receptor for SARS-CoV-2 spike protein, which precipitates replication of the virus in the old population. On the other hand, immune dysregulation and changes in gut microbiota as a result of aging can contribute to the cytokine storm, one of the main indicators of disease severity. Decrement in sex steroids, especially in women, as well as growth hormone, both of which have crucial roles in immune regulation, is a key contributor to disease severity in old age. Senescence-associated oxidative stress and mitochondrial dysfunction in both pneumocytes and immune cells contribute to the severity of infection in an exacerbative manner. In addition, lifestyle-associated factors such as nutrition and physical activity, which are compromised in old age, are known as important factors in COVID-19 infection. Aging-associated comorbidities, especially cardiovascular diseases and diabetes mellitus, also put older adults at an increased risk of complications, and disease severity.