Hyperinflammation and derangement of renin-angiotensin-aldosterone system in COVID-19: A novel hypothesis for clinically suspected hypercoagulopathy and microvascular immunothrombosis

Coronary microvascular dysfunction pathophysiology in COVID-19

Recently, accumulating evidence has highlighted the role of endothelial dysfunction in COVID-19 progression. Coronary microvascular dysfunction (CMD) plays a pivotal role in cardiovascular disease (CVD) and CVD-related risk factors (eg, age, gender, hypertension, diabetes mellitus, and obesity). Equally, these are also risk factors for COVID-19. The purpose of this review was to explore CMD pathophysiology in COVID-19, based on recent evidence. COVID-19 mechanisms were reviewed in terms of imbalanced renin-angiotensin-aldosterone-systems (RAAS), systemic inflammation and immune responses, endothelial dysfunction, and coagulatory disorders. Based on these mechanisms, we addressed CMD pathophysiology within the context of COVID-19, from five perspectives. The first was the disarrangement of local RAAS and Kallikrein-kinin-systems attributable to SARS-Cov-2 entry, and the concomitant decrease in coronary microvascular endothelial angiotensin I converting enzyme 2 (ACE2) levels. The second was related to coronary microvascular obstruction, induced by COVID-19-associated systemic hyper-inflammation and pro-thrombotic state. The third was focused on how pneumonia/acute respiratory distress syndrome (ARDS)-related systemic hypoxia elicited oxidative stress in coronary microvessels and cardiac sympathetic nerve activation. Fourthly, we discussed how autonomic nerve dysfunction mediated by COVID-19-associated mental, physical, or physiological factors could elicit changes in coronary blood flow, resulting in CMD in COVID-19 patients. Finally, we analyzed reciprocity between the coronary microvascular endothelium and perivascular cellular structures due to viremia, SARS-CoV-2 dissemination, and systemic inflammation. These mechanisms may function either consecutively or intermittently, finally culminating in CMD-mediated cardiovascular symptoms in COVID-19 patients. However, the underlying molecular pathogenesis remains to be clarified.

Prevalence and mortality of COVID-19 are associated with the L55M functional polymorphism of Paraoxonase 1

Introduction

Accumulating evidence recommends that infectious diseases including coronavirus disease 2019 (COVID-19) are often associated with oxidative stress and inflammation. Paraoxonase 1 (PON1, OMIM: 168,820), a member of the paraoxonase gene family, has antioxidant properties. Enzyme activity of paraoxonase depends on a variety of influencing factors such as polymorphisms of PON1, ethnicity, gender, age, and a number of environmental variables. The PON1 has two common functional polymorphisms, namely, Q192R (rs662) and L55M (rs854560). The R192 and M55 alleles are associated with increase and decrease in enzyme activity, respectively.

Objective

The present study was conducted to investigate the possible association of rs662 and rs854560 polymorphisms with morbidity and mortality of COVID-19.

Methods

Data for the prevalence, mortality, and amount of accomplished diagnostic test (per 10⁶ people) on 25 November 2020 from 48 countries were included in the present study. The Human Development Index (HDI) was used as a potential confounding variable.

Results

The frequency of M55 was positively correlated with the prevalence (partial r = 0.487, df = 36, p = 0.002) and mortality of COVID-19 (partial r = 0.551, df = 36, p < 0.001), after adjustments for HDI and amount of the accomplished diagnostic test as possible confounders.

Conclusions

This means that countries with higher M55 frequency have higher prevalence and mortality of COVID-19.

The State of Microcirculatory Hemodynamics in Patients with Moderate and Severe COVID-19

Microcirculatory hemodynamic indexes (HI) were assessed in patients with moderate and severe COVID-19. In both groups, a significant increase in the absolute spectral indexes (HI1, HI2, and HI3) and the ratio of low-frequency to high-frequency component (HI1/HI3) was revealed. In the group of severe infection, only the “slow” index (low-frequency HI1) of microcirculatory hemodynamics was significantly lower. The oscillatory indices MAYER1-3 and RESP1-3 were reduced in patients of both groups. The aggravation of the disease course was accompanied by depression of the low-frequency index HI1. Regulatory shifts compensate for disturbances in microcirculatory processes in moderate COVID-19, but severe course was associated with their decompensation.

Coronavirus Disease 2019 Infection among Children: Pathogenesis, Treatment, and Outcome

Coronavirus disease 2019 (COVID-19) is a contagious disease that may lead to respiratory distress syndrome and even death. Neonates and children are most vulnerable population to COVID-19 infection; however, the infection is usually milder and has a better prognosis in pediatric patients compared with adults. It remains unclear why pediatric population is less symptomatic than adults. Children frequently experience respiratory infections and their immune system is in developing stage. However, large proportion of the asymptomatic pediatric population may contribute to transmission. This review explored several aspects of COVID-19 infection such as its epidemiology, its molecular pathogenesis with respect to angiotensin-converting enzyme 2 receptor and inflammatory mediators, intrauterine vertical transmission, imaging findings, and complications like cytokine release syndrome (multisystem inflammatory syndrome in children). We also looked at prognostic factors and treatment modalities like corticosteroids, RNA replicate inhibitors, protease inhibitors, Bruton tyrosine kinase inhibitor, that is, acalabrutinib and convalescent plasma therapy. Since there is no strong evidence for the intrauterine transmission, early isolation should be performed to protect a neonate from a COVID-19 infected mother. Development of vaccine and an effective antiviral drug are the need of the hour.

COVID-19-related coagulopathy: A review of pathophysiology and pharmaceutical management

December 2019 will never be forgotten in the history of medicine when an outbreak of pneumonia of unknown etiology in Wuhan, China sooner or later prompted the World Health Organization to issue a public health warning emergency. This is not the first nor will it be the last time that a member of β-coronaviruses (CoVs) is waging a full-scale war against human health. Notwithstanding the fact that pneumonia is the primary symptom of the novel coronavirus (2019nCoV; designated as SARS-CoV-2), the emergence of severe disease mainly due to the injury of nonpulmonary organs at the shadow of coagulopathy leaves no choice, in some cases, rather than a dreadful death. Multiple casual factors such as inflammation, endothelial dysfunction, platelet and complement activation, renin-angiotensin-aldosterone system derangement, and hypoxemia play a major role in the pathogenesis of coagulopathy in coronavirus disease 2019 (COVID-19) patients. Due to the undeniable role of coagulation dysfunction in the initiation of several complications, assessment of coagulation parameters and the platelet count would be beneficial in early diagnosis and also timely prediction of disease severity. Although low-molecular-weight heparin is considered as the first-line of treatment in COVID-19-associated coagulopathy, several possible therapeutic options have also been proposed for better management of the disease. In conclusion, this review would help us to gain insight into the pathogenesis, clinical manifestation, and laboratory findings associated with COVID-19 coagulopathy and would summarize management strategies to alleviate coagulopathy-related complications.

Endothelial Dysfunction, Inflammation, and Oxidative Stress in COVID-19-Mechanisms and Therapeutic Targets

The outbreak of the COVID-19 pandemic represents an ongoing healthcare emergency responsible for more than 3.4 million deaths worldwide. COVID-19 is the disease caused by SARS-CoV-2, a virus that targets not only the lungs but also the cardiovascular system. COVID-19 can manifest with a wide range of clinical manifestations, from mild symptoms to severe forms of the disease, characterized by respiratory failure due to severe alveolar damage. Several studies investigated the underlying mechanisms of the severe lung damage associated with SARS-CoV-2 infection and revealed that the respiratory failure associated with COVID-19 is the consequence not only of acute respiratory distress syndrome but also of macro- and microvascular involvement. New observations show that COVID-19 is an endothelial disease, and the consequent endotheliopathy is responsible for inflammation, cytokine storm, oxidative stress, and coagulopathy. In this review, we show the central role of endothelial dysfunction, inflammation, and oxidative stress in the COVID-19 pathogenesis and present the therapeutic targets deriving from this endotheliopathy.

COVID-19 Immunobiology: Lessons Learned, New Questions Arise

There is strong evidence that COVID-19 pathophysiology is mainly driven by a spatiotemporal immune deregulation. Both its phenotypic heterogeneity, spanning from asymptomatic to severe disease/death, and its associated mortality, are dictated by and linked to maladaptive innate and adaptive immune responses against SARS-CoV-2, the etiologic factor of the disease. Deregulated interferon and cytokine responses, with the contribution of immune and cellular stress-response mediators (like cellular senescence or uncontrolled inflammatory cell death), result in innate and adaptive immune system malfunction, endothelial activation and inflammation (endothelitis), as well as immunothrombosis (with enhanced platelet activation, NET production/release and complement hyper-activation). All these factors play key roles in the development of severe COVID-19. Interestingly, another consequence of this immune deregulation, is the production of autoantibodies and the subsequent development of autoimmune phenomena observed in some COVID-19 patients with severe disease. These new aspects of the disease that are now emerging (like autoimmunity and cellular senescence), could offer us new opportunities in the field of disease prevention and treatment. Simultaneously, lessons already learned from the immunobiology of COVID-19 could offer new insights, not only for this disease, but also for a variety of chronic inflammatory responses observed in autoimmune and (auto)inflammatory diseases.

Involvement of Inflammation in Venous Thromboembolic Disease: An Update in the Age of COVID-19

The inflammatory process is strongly involved in the pathophysiology of venous thromboembolism (VTE) and has a significant role in disease prediction. Inflammation most probably represents a common denominator through which classical and nonclassical risk factors stimulate thrombotic process. Inflammation of the venous wall promotes the release of tissue factor, inhibits the release of anticoagulant factors, and hampers endogenous fibrinolysis. Systemic inflammatory response also inhibits restoration of blood flow in the occluded vessel. Recent studies indicate that increased inflammatory response ("cytokine storm") is related to prothrombotic state and thromboembolic events in patients with coronavirus disease 2019 (COVID-19). The growing evidence of involvement of inflammation in the pathogenesis of VTE indicates the importance of anti-inflammatory treatment and prevention of VTE. While aspirin was shown to be effective in prevention of recurrent venous thrombosis after treatment with anticoagulant drugs, some other anti-inflammatory drugs like nonsteroidal anti-inflammatory agents may have prothrombotic effect, thus potentially increasing the risk of VTE. Recently, new specific anti-inflammatory drug inhibitors of inflammatory markers that have been shown to be involved in the pathogenesis of VTE are being searched. As thrombogenesis is based on activation of coagulation provoked by inflammation, then prevention and treatment of VTE should include both anticoagulant and anti-inflammatory agents. Combined treatment is related to increased risk of bleeding complications, therefore subtherapeutic doses of both drugs should be used to improve the efficacy of management of VTE without increasing the risk of bleeding.

A new haematocytometric index: Predicting severity and mortality risk value in COVID-19 patients

INTRODUCTION

Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 virus, is a major public health concern spanning from healthy carriers to patients with life-threatening conditions. Although most of COVID-19 patients have mild-to-moderate clinical symptoms, some patients have severe pneumonia leading to death. Therefore, the early prediction of disease prognosis and severity is crucial in COVID-19 patients. The main objective of this study is to evaluate the haemocytometric parameters and identify severity score associated with SARS-CoV-2 infection.

METHODS

Clinical and laboratory records were retrospectively reviewed from 97 cases of COVID-19 admitted to hospitals in Istanbul, Turkey. The patient groups were subdivided into three major groups: Group 1 (Non-critical): 59 patients, Group 2 (Critical-Survivors): 23 patients and Group 3 (Critical-Non-survivors):15 patients. These data was tested for correlation, including with derived haemocytometric parameters. The blood analyses were performed the Sysmex XN-series automated hematology analyser using standard laboratory protocols. All statistical testing was undertaken using Analyse-it software.

RESULTS

97 patients with COVID-19 disease and 935 sequential complete blood count (CBC-Diff) measurements (days 0-30) were included in the final analyses. Multivariate analysis demonstrated that red cell distribution width (RDW) (>13.7), neutrophil to lymphocyte ratio (NLR) (4.4), Hemoglobin (Hgb) (<11.4 gr/dL) and monocyte to neutrophil ratio (MNR) (0.084) had the highest area under curve (AUC) values, respectively in discrimination critical patients than non-critical patients. In determining Group 3, MNR (<0.095), NLR (>5.2), Plateletcount (PLT) (>142 x103/L) and RDW (>14) were important haemocytometric parameters, and the mortality risk value created by their combination had the highest AUC value (AUC = 0.911, 95% CI, 0886-0.931). Trend analysis of CBC-Diff parameters over 30 days of hospitalization, NLR on day 2, MNR on day 4, RDW on day 6 and PLT on day 7 of admission were found to be the best time related parameters in discrimination non-critical (mild-moderate) patient group from critical (severe and non-survivor) patient group.

CONCLUSION

NLR is a strong predictor for the prognosis for severe COVID-19 patients when the cut-off chosen was 4.4, the combined mortality risk factor COVID-19 disease generated from RDW-CV, NLR, MNR and PLT is best as a mortality haematocytometric index.

COVID-19 and immunothrombosis: emerging understanding and clinical management

The COVID-19 pandemic has been the most significant health crisis in recent global history. Early studies from Wuhan highlighted COVID-19-associated coagulopathy and a significant association with mortality was soon recognised. As research continues across the world, more evidence is emerging of the cross-talk between the innate immune system, coagulation activation and inflammation. Immunothrombosis has been demonstrated to play a key role in the pathophysiology of severe COVID-19, with extracellular histones and neutrophil extracellular traps detected in the plasma and cardiopulmonary tissues of critically ill patients. Targeting the components of immunothrombosis is becoming an important factor in the treatment of patients with COVID-19 infection. Recent studies report outcomes of intermediate and therapeutic anticoagulation in hospitalised patients with varying severities of COVID-19 disease, including optimal dosing and associated bleeding risks. Immunomodulatory therapies, including corticosteroids and IL-6 receptor antagonists, have been demonstrated to significantly reduce mortality in COVID-19 patients. As the pandemic continues, more studies are required to understand the driving factors and upstream mechanisms for coagulopathy and immunothrombosis in COVID-19, and thus potentially develop more targeted therapies for SARS-CoV-2 infection, both in the acute phase and in those who develop longer-term symptom burden.

Status of mannose-binding lectin (MBL) and complement system in COVID-19 patients and therapeutic applications of antiviral plant MBLs

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by a virus called "Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)." In the majority of patients, infection with COVID-19 may be asymptomatic or may cause only mild symptoms. However, in some patients, there can also be immunological problems, such as macrophage activation syndrome (CSS) that results in cytokine storm syndrome (CSS) and acute respiratory distress syndrome (ARDS). Comprehension of host-microbe communications is the critical aspect in the advancement of new therapeutics against infectious illnesses. Endogenous animal lectins, a class of proteins, may perceive non-self glycans found on microorganisms. Serum mannose-binding lectin (sMBL), as a part of the innate immune framework, recognizes a wide range of microbial microorganisms and activates complement cascade via an antibody-independent pathway. Although the molecular basis for the intensity of SARS-CoV-2 infection is not generally understood, scientific literature indicates that COVID-19 is correlated with unregulated activation of the complement in terms of disease severity. Disseminated intravascular coagulation (DIC), inflammation, and immune paralysis contribute to unregulated complement activation. Pre-existing genetic defects in MBL and their association with complement play a major role in immune response dysregulation caused by SARS-CoV-2. In order to generate anti-complement-based therapies in Covid-19, an understanding of sMBL in immune response to SARS-CoV-2 and complement is therefore essential. This review highlights the role of endogenous sMBL and complement activation during SARS-CoV-2 infection and their therapeutic management by various agents, mainly plant lectins, since antiviral mannose-binding plant lectins (pMBLs) offer potential applications in the prevention and control of viral infections.

Demyelination as a result of an immune response in patients with COVID-19

The coronavirus disease of 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus-2 (SARS CoV-2), that already appeared as a global pandemic. Presentation of the disease often includes upper respiratory symptoms like dry cough, dyspnea, chest pain, and rhinorrhea that can develop to respiratory failure, needing intubation. Furthermore, the occurrence of acute and subacute neurological manifestations such as stroke, encephalitis, headache, and seizures are frequently stated in patients with COVID-19. One of the reported neurological complications of severe COVID-19 is the demolition of the myelin sheath. Indeed, the complex immunological dysfunction provides a substrate for the development of demyelination. Nevertheless, few published reports in the literature describe demyelination in subjects with COVID-19. In this short narrative review, we discuss probable pathological mechanisms that may trigger demyelination in patients with SARS-CoV-2 infection and summarize the clinical evidence, confirming SARS-CoV-2 condition as a risk factor for the destruction of myelin.

Cardiovascular injuries and SARS-COV-2 infection: focus on elderly people

The novel coronavirus disease (COVID-19) has hit the healthcare system worldwide. The risk of severe infection and mortality increases with advancing age, especially in subjects with comorbidities such as cardiovascular disease, hypertension, diabetes, obesity and cancer. Moreover, cardiovascular complications such as myocardial injury, heart failure and thromboembolism are frequently observed in COVID-19 cases, and several biomarkers (troponin, NTproBNP and D-Dimer) have been identified as prognostic indicators of disease severity and worst outcome. Currently, there is no specific therapy against SARS-CoV-2, although many medications are under investigation. The aim of this review will be to explore the intertwined relationship between COVID-19 disease and the cardiovascular system, focusing on elderly population. The available supportive treatments along with the related concerns in elderly patients, due to their comorbidities and polypharmacotherapy, will be explored.

Hypotheses and facts for genetic factors related to severe COVID-19

Genome-wide association analysis allows the identification of potential candidate genes involved in the development of severe coronavirus disease 2019 (COVID-19). Hence, it seems that genetics matters here, as well. Nevertheless, the virus's nature, including its RNA structure, determines the rate of mutations leading to new viral strains with all epidemiological and clinical consequences. Given these observations, we herein comment on the current hypotheses about the possible role of the genes in association with COVID-19 severity. We discuss some of the major candidate genes that have been identified as potential genetic factors associated with the COVID-19 severity and infection susceptibility: HLA, ABO, ACE2, TLR7, ApoE, TYK2, OAS, DPP9, IFNAR2, CCR2, etc. Further study of genes and genetic variants will be of great benefit for the prevention and assessment of the individual risk and disease severity in different populations. These scientific data will serve as a basis for the development of clinically applicable diagnostic and prognostic tests for patients at high risk of COVID-19.

Understanding COVID-19-associated coagulopathy: From PIC to SIC or DIC

Coagulopathy, characterized by a high D-dimer level, is a common pathological occurrence in coronavirus disease 2019 (COVID-19) and is associated with poor prognosis. Severe cases with COVID-19 is associated with a significantly higher risk of deep vein thrombosis and acute pulmonary embolism. Pulmonary intravascular coagulopathy is the characteristic coagulopathy in COVID-19. Unlike sepsis-induced coagulopathy and disseminated intravascular coagulation, which are manifestations of systemic coagulopathy, pulmonary intravascular coagulopathy is a manifestation of a local coagulation disorder in the lung. The progression from pulmonary intravascular coagulopathy to sepsis-induced coagulopathy or disseminated intravascular coagulation in the context of COVID-19 may indicate that the patient's coagulation dysfunction has progressed from local to systemic. Exploring the associated coagulation disease will aid in the understanding of the pathophysiological mechanisms underlying severe COVID-19.

Nervous System Involvement in COVID-19: a Review of the Current Knowledge

The current pandemic of the new human coronavirus (CoV), i.e., severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has created an urgent global condition. The disease, termed coronavirus disease 2019 (COVID-19), is primarily known as a respiratory tract infection. Although SARS-CoV-2 directly invades the lungs, COVID-19 is a complex multi-system disease with varying degrees of severity and affects several human systems including the cardiovascular, respiratory, gastrointestinal, neurological, hematopoietic, and immune systems. From the existing data, most COVID-19 cases develop a mild disease typically presented with fever and respiratory illness. However, in some patients, clinical evidence suggests that COVID-19 might progress to acute respiratory distress syndrome (ARDS), multi-organ dysfunction, and septic shock resulting in a critical condition. Likewise, specific organ dysfunction seems to be related to the disease complication, worsens the condition, and increases the lethality of COVID-19. The neurological manifestations in association with disease severity and mortality have been reported in COVID-19 patients. Despite the continuously increasing reports of the neurological symptoms of SARS-CoV-2, our knowledge about the possible routes of nervous system involvement associated with COVID-19 is limited. Herein, we will primarily describe the critical aspects and clinical features of SARS-CoV-2 related to nervous system impairment and then discuss possible routes of SARS-CoV-2 nervous system involvement based on the current evidence.

Imaging in the COVID-19 era: Lessons learned during a pandemic

The first year of the coronavirus disease 2019 (COVID-19) pandemic has been a year of unprecedented changes, scientific breakthroughs, and controversies. The radiology community has not been spared from the challenges imposed on global healthcare systems. Radiology has played a crucial part in tackling this pandemic, either by demonstrating the manifestations of the virus and guiding patient management, or by safely handling the patients and mitigating transmission within the hospital. Major modifications involving all aspects of daily radiology practice have occurred as a result of the pandemic, including workflow alterations, volume reductions, and strict infection control strategies. Despite the ongoing challenges, considerable knowledge has been gained that will guide future innovations. The aim of this review is to provide the latest evidence on the role of imaging in the diagnosis of the multifaceted manifestations of COVID-19, and to discuss the implications of the pandemic on radiology departments globally, including infection control strategies and delays in cancer screening. Lastly, the promising contribution of artificial intelligence in the COVID-19 pandemic is explored.

Mesenteric ischemia in COVID-19 patients: A review of current literature

BACKGROUND

Coronavirus disease 2019 (COVID-19) virus has affected all the systems of the body, defying all impressions of it being a respiratory virus only.

AIM

To see the association of mesenteric ischemia with COVID-19.

METHODS

After initial screening and filtering of the titles on PubMed and Google Scholar, 124 articles were selected. Articles were read in full, and the references were skimmed for relevance. Twenty-six articles (case reports and case series) were found to eligible for inclusion. References of these 26 articles were checked for any additional cases. Two more publications were found, and a total of 28 articles (22 case reports and 6 case series) have been included for review in this manuscript.

RESULTS

A total of 41 cases of acute mesenteric ischemia in COVID-19 patients have been reported in the literature since the outbreak of this pandemic. Most of them include patients with comorbidities.

CONCLUSION

In conclusion, based on this literature review and precise published knowledge regarding acute mesenteric ischemia in patients with COVID-19, it is essential to understand its relevance in all patients with gastrointestinal symptoms. The threshold for the diagnostic investigations should also be kept low for the timely diagnosis and management of this disorder.

Risk Factors For Kidney Damage In COVID-19 Patients Admitted To The Intensive Care Unit

Background — Acute kidney injury (AKI) reaches 29% in the intensive care unit (ICU). Our study aimed to determine the prevalence, features, and the main AKI factors in critically ill patients with coronavirus disease 2019 (COVID-19). Material and Methods — The study included 37 patients with COVID-19. We analyzed the total blood count test results, biochemical profile panel, coagulation tests, and urine samples. We finally estimated the markers of kidney damage and mortality. Result — All patients in ICU had proteinuria, and 80.5% of patients had hematuria. AKI was observed in 45.9% of patients. Independent risk factors were age more than 60 years, increased C-reactive protein (CRP) level, and decreased platelet count. Conclusion — Kidney damage was observed in most critically ill patients with COVID-19. The independent risk factors for AKI in critically ill patients were elderly age, a cytokine response with a high CRP level.

A Multidisciplinary Approach to Coronavirus Disease (COVID-19)

Since December 2019, humanity has faced an important global threat. Many studies have been published on the origin, structure, and mechanism of action of the SARS-CoV-2 virus and the treatment of its disease. The priority of scientists all over the world has been to direct their time to research this subject. In this review, we highlight chemical studies and therapeutic approaches to overcome COVID-19 with seven different sections. These sections are the structure and mechanism of action of SARS-CoV-2, immunotherapy and vaccine, computer-aided drug design, repurposing therapeutics for COVID-19, synthesis of new molecular structures against COVID-19, food safety/security and functional food components, and potential natural products against COVID-19. In this work, we aimed to screen all the newly synthesized compounds, repurposing chemicals covering antiviral, anti-inflammatory, antibacterial, antiparasitic, anticancer, antipsychotic, and antihistamine compounds against COVID-19. We also highlight computer-aided approaches to develop an anti-COVID-19 molecule. We explain that some phytochemicals and dietary supplements have been identified as antiviral bioproducts, which have almost been successfully tested against COVID-19. In addition, we present immunotherapy types, targets, immunotherapy and inflammation/mutations of the virus, immune response, and vaccine issues.

Outcomes of Extracorporeal Membrane Oxygenation for Acute Respiratory Distress Syndrome in COVID-19 Patients: A Propensity-Matched Analysis

It remains unclear to what extent the outcomes and complications of extracorporeal membrane oxygenation (ECMO) therapy in COVID-19 patients with acute respiratory distress syndrome (ARDS) differ from non-COVID-19 ARDS patients. In an observational, propensity-matched study, outcomes after ECMO support were compared between 19 COVID-19 patients suffering from ARDS (COVID group) and 34 matched non-COVID-19 ARDS patients (NCOVID group) from our historical cohort. A 1:2 propensity matching was performed based on respiratory ECMO survival prediction (RESP) score, age, gender, bilirubin, and creatinine levels. Patients' characteristics, laboratory parameters, adverse events, and 90-day survival were analyzed. Patients' characteristics in COVID and NCOVID groups were similar. Before ECMO initiation, fibrinogen levels were significantly higher in the COVID group (median: 493 vs. 364 mg/dL, p < 0.001). Median ECMO support duration was similar (16 vs. 13 days, p = 0.714, respectively). During ECMO therapy, patients in the COVID group developed significantly more thromboembolic events (TEE) than did those in the NCOVID group (42% vs. 12%, p = 0.031), which were mainly pulmonary artery embolism (PAE) (26% vs. 0%, p = 0.008). The rate of major bleeding events (42% vs. 62%, p = 0.263) was similar. Fibrinogen decreased significantly more in the COVID group than in the NCOVID group (p < 0.001), whereas D-dimer increased in the COVID group (p = 0.011). Additionally, 90-day mortality did not differ (47% vs. 74%; p = 0.064) between COVID and NCOVID groups. Compared with that in non-COVID-19 ARDS patients, ECMO support in COVID-19 patients was associated with comparable in-hospital mortality and similar bleeding rates but a higher incidence of TEE, especially PAE. In contrast, coagulation parameters differed between COVID and NCOVID patients.

Mutations and polymorphisms in genes involved in the infections by covid 19: a review

Covid19 is the third most aggressive coronavirus that spreads rapidly and kills many people. It is a multigenic and multifactorial disease with many genetic and environmental determinants. The identification of these factors is key to better understanding the etiology of Covid-19 and it can also help predict the risk and prevent Covid-19 infection. Many predisposing factors have been described for this coronavirus such as advanced age, male gender, and geographic location. In addition to these elements, genetic factors have an important role in Covid19 infection. Interindividual variation in susceptibility to infection by Covid-19 has been associated with to the presence of genetic polymorphisms in many genes, especially in those that code for proteins implicated in the infection process. The present review gives a brief overview of different genes involved in the infection by SARS-CoV-2 and its association with disease severity. The results of our research showed that many different genes are associated with a higher risk for COVID-19, notably those coding for proteins involved in coronavirus-cell entry and fusion such as ACE2 (angiotensin I converting enzyme 2), TMPRSS2 (transmembrane protease, serine 2) and CD26.

Protective Effects of Statins Administration in European and North American Patients Infected with COVID-19: A Meta-Analysis

Severe acute respiratory syndrome coronavirus 2 has spread rapidly throughout the world, becoming an overwhelming global health emergency. The array of injuries caused by this virus is broad and not limited to the respiratory system, but encompassing also extensive endothelial and systemic tissue damage. Since statins effectively improve endothelial function, these drugs may have beneficial effects in patients with coronavirus disease 2019 (COVID-19). Therefore, this investigation aimed to provide an updated overview on the interplay between statins and COVID-19, with particular focus on their potentially protective role against progression toward severe or critical illness and death. A systematic electronic search was performed in Scopus and PubMed up to present time. Data on statins use and COVID-19 outcomes especially in studies performed in Europe and North America were extracted and pooled. A total of seven studies met our inclusion criteria, totaling 2,398 patients (1,075 taking statins, i.e., 44.8%). Overall, statin usage in Western patients hospitalized with COVID-19 was associated with nearly 40% lower odds of progressing toward severe illness or death (odds ratio: 0.59; 95% confidence interval: 0.35-0.99). After excluding studies in which statin therapy was started during hospital admission, the beneficial effect of these drugs was magnified (odds ratio: 0.51; 95% confidence interval: 0.41-0.64). In conclusion, although randomized trials would be necessary to confirm these preliminary findings, current evidence would support a favorable effect of statins as adjuvant therapy in patients with COVID-19. Irrespective of these considerations, suspension of statin therapy seems highly unadvisable in COVID-19 patients.

Acute kidney injury and mortality in coronavirus disease 2019: results from a cohort study of 1,280 patients

BACKGROUND

The development of acute kidney injury (AKI) in patients with coronavirus disease 2019 (COVID-19) is associated with a high risk of death. Published data demonstrate the possibility of severe kidney injury in patients suffering from COVID-19. However, these data are still controversial.

METHODS

A total of 1,280 patients with a proven diagnosis of COVID-19 were included in our study. COVID-19 was confirmed in all patients using reverse transcriptase polymerase chain reaction test of a nasopharyngeal swab, and based on the typical computed tomography findings. Demographic data, underlying comorbidities, and laboratory blood tests were assessed. We assessed the incidence of AKI and its associated mortality defined by survival status at discharge.

RESULTS

Proteinuria was identified with 648 patients (50.6%) with COVID-19. AKI was identified in 371 patients (29.0%). Ten of these patients (2.7%) required dialysis. The risk factors for AKI included age of > 65 years, augmentation of C-reactive protein, ferritin and an increase in values of activated partial thromboplastin time. Overall, 162 of the 1,280 hospitalized patients (12.7%) and 111 of the 371 patients (29.9%) with AKI did not survive. The hazard ratio (HR) for mortality was 3.96 (95% confidence interval, 2.83-5.54) for patients with AKI vs. no AKI.

CONCLUSION

AKI was a relatively common finding among patients with COVID-19. The risk factors for AKI in COVID-19 included old age, the inflammatory response, the severity of lung involvement, and disseminated intravascular coagulation. These same factors, in addition to arterial hypertension, were found to increase the risk of mortality.

Ischemic Stroke: An Underestimated Complication of COVID-19

The coronavirus disease 2019 (COVID-19) has spread rapidly as a pandemic around the world. In addition to severe acute respiratory syndrome, more and more studies have focused on the complication of COVID-19, especially ischemic stroke. Here, we propose several pathophysiological processes and possible mechanisms underlying ischemic stroke after COVID-19 for early prevention and better treatment of COVID-19-related stroke.

Intracerebral Hemorrhage in COVID-19 Patients with Pulmonary Failure: A Propensity Score-Matched Registry Study

BACKGROUND

Hypercoagulability in Coronavirus Disease 2019 (COVID-19) causes deep vein thrombosis and pulmonary embolism necessitating systemic anticoagulation. Case reports of intracerebral hemorrhages in ventilated COVID-19 patients warrant precaution. It is unclear, however, if COVID-19 patients with acute respiratory distress syndrome (ARDS) with or without veno-venous extracorporeal membrane oxygenation therapy (VV-ECMO) have more intracerebral hemorrhages (ICH) compared to other ARDS patients.

METHODS

We conducted a retrospective observational single-center study enrolling all patients with ARDS from 01/2018 to 05/2020. PCR-positive SARS-CoV-2 patients with ARDS were allocated to the COVID-19 group. Propensity score matching was performed for age, VV-ECMO, and bleeding risk.

RESULTS

A total of 163 patients with moderate or severe ARDS were identified, 47 (28.8%) in the COVID-19 group, and 116 (71.2%) in the non-COVID-19 group. In 63/163 cases (38.7%), VV-ECMO therapy was required. The ICU survival was 52.8%. COVID-19 patients were older, more often male, and exhibited a lower SOFA score, but the groups showed similar rates of VV-ECMO therapy. Treatments with antiplatelet agents (p = 0.043) and therapeutic anticoagulation (p = 0.028) were significantly more frequent in the COVID-19 patients. ICH was detected in 22 patients (13.5%) with no statistical difference between the groups (11.2 vs. 19.1% without and with SARS-CoV-2, respectively, p = 0.21). Propensity score matching confirmed similar rates of ICH in both groups (12.8 vs. 19.1% without and with SARS-CoV-2, respectively, p = 0.57), thus leveling out possible confounders.

CONCLUSIONS

Intracerebral hemorrhage was detected in every tenth patient with ARDS. Despite statistically higher rates of antiplatelet therapy and therapeutic anticoagulation in COVID-19 patients, we found a similar rate of ICH in patients with ARDS due to COVID-19 compared to other causes of ARDS.

Complement levels at admission as a reflection of coronavirus disease 2019 (COVID-19) severity state

Complement system hyperactivation has been proposed as a potential driver of adverse outcomes in severe acute respiratory syndrome coronavirus 2 infected patients, given prior research of complement deposits found in tissue and blood samples, as well as evidence of clinical improvement with anticomplement therapy. Its role in augmenting thrombotic microangiopathy mediated organ damage has also been implicated in coronavirus disease 2019 (COVID‐19). This study aimed to examine associations between complement parameters and progression to severe COVID‐19 illness, as well as correlations with other systems. Blood samples of COVID‐19 patients presenting to the emergency department (ED) were analyzed for a wide panel of complement and inflammatory biomarkers. The primary outcome was COVID‐19 severity at index ED visit, while the secondary outcome was peak disease severity over the course of illness. Fifty‐two COVID‐19 patients were enrolled. C3a (p = 0.018), C3a/C3 ratio (p = 0.002), and sC5b‐9/C3 ratio (p = 0.021) were significantly elevated in with severe disease at ED presentation. Over the course of illness, C3a (p = 0.028) and C3a/C3 ratio (p = 0.003) were highest in the moderate severity group. In multivariate regression controlled for confounders, complement hyperactivation failed to predict progression to severe disease. C3a, C3a/C3 ratio, and sC5b‐9/C3 ratio were correlated positively with numerous inflammatory biomarkers, fibrinogen, and VWF:Ag, and negatively with plasminogen and ADAMTS13 activity. We found evidence of complement hyperactivation in COVID‐19, associated with hyperinflammation and thrombotic microangiopathy. Complement inhibition should be further investigated for potential benefit in patients displaying a hyperinflammatory and microangiopathic phenotype.

Perinatal SARS-CoV-2 Infection and Neonatal COVID-19: A 2021 Update

The coronavirus disease 2019 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has swept across the world like an indiscriminating wildfire. Pregnant women and neonates are particularly vulnerable to this infection compared with older children and healthy young adults, with unique challenges in their management. Unfamiliarity with the consequences of this novel virus and lack of high-quality data led to considerable heterogeneity in obstetrical and neonatal management early in the pandemic. The aim of the this review is to summarize the impact of SARS-CoV-2 infection on pregnancy and childbirth and to examine care and possible outcomes for neonates with Covid-19-positive mothers. A brief review of vaccines currently approved by the United States Food and Drug Administration for emergency use and their potential effects on pregnant and lactating women in included.

Postmortem Findings Associated With SARS-CoV-2: Systematic Review and Meta-analysis

Coronavirus Disease 2019 (COVID-19), caused by the novel Severe Acute Respiratory Syndrome-associated Coronavirus 2 (SARS-CoV-2), has become a global threat to public health. COVID-19 is more pathogenic and infectious than the prior 2002 pandemic caused by SARS-CoV-1. The pathogenesis of certain disease manifestations in COVID-19 such as diffuse alveolar damage (DAD) are thought to be similar to SARS-CoV-1. However, the exact pathogenesis of COVID-19 related deaths remains poorly understood. The aim of this article was to systematically summarize the rapidly emerging literature regarding COVID-19 autopsies. A meta-analysis was also conducted based on data accrued from preprint and published articles on COVID-19 (n=241 patients) and the results compared with postmortem findings associated with SARS-CoV-1 deaths (n=91 patients). Both autopsy groups included mostly adults of median age 70 years with COVID-19 and 50 years with SARS-CoV-1. Overall, prevalence of DAD was more common in SARS-CoV-1 (100.0%) than COVID-19 (80.9%) autopsies (P=0.001). Extrapulmonary findings among both groups were not statistically significant except for hepatic necrosis (P <0.001), splenic necrosis (P<0.006) and white pulp depletion (P <0.001) that were more common with SARS-CoV-1. Remarkable postmortem findings in association with COVID-19 apart from DAD include pulmonary hemorrhage, viral cytopathic effect within pneumocytes, thromboembolism, brain infarction, endotheliitis, acute renal tubular damage, white pulp depletion of the spleen, cardiac myocyte necrosis, megakaryocyte recruitment, and hemophagocytosis.

Perinatal SARS-CoV-2 Infection and Neonatal COVID-19: A 2021 Update

The coronavirus disease 2019 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has swept across the world like an indiscriminating wildfire. Pregnant women and neonates are particularly vulnerable to this infection compared with older children and healthy young adults, with unique challenges in their management. Unfamiliarity with the consequences of this novel virus and lack of high-quality data led to considerable heterogeneity in obstetrical and neonatal management early in the pandemic. The aim of the this review is to summarize the impact of SARS-CoV-2 infection on pregnancy and childbirth and to examine care and possible outcomes for neonates with Covid-19-positive mothers. A brief review of vaccines currently approved by the United States Food and Drug Administration for emergency use and their potential effects on pregnant and lactating women in included.

Thrombose und COVID-19

Die Prävalenz der venösen thromboembolischen (VTE) Ereignisse ist bei Coronavirus diesease 2019 (COVID-19) -Patienten hoch, insbesondere bei schwer Erkrankten. Patienten mit schwerer COVID-19 und VTE haben eine signifikant höhere Mortalität im Vergleich zu Patienten ohne VTE. Die Manifestation einer schweren Infektion mit Severe acute respiratory syndrome coronavirus-2 (SARS-CoV‑2) entspricht einem systemischen proinflammatorischen und prokoagulatorischen Phänotyp, der mit vaskulären Thrombosen nicht nur in den Venen, sondern auch in den Arterien, Kapillaren sowie mit einer Inflammation der Gefäße assoziiert ist. Ein erhöhter D‑Dimer-Spiegel kann als Indikator für VTE bei Patienten mit COVID-19 verwendet werden. Die meisten medizinischen Gesellschaften empfehlen eine VTE-Prophylaxe vorzugsweise mit niedermolekularen Heparinen (LMWH) bei allen stationären Patienten. Weitere Daten von randomisierten kontrollierten Studien (RCTs) über die optimale Antikoagulation und antithrombotische Therapie werden in der nahen Zukunft erwartet.

Acute Bilateral Femoral Arterial Thrombosis in a Young Adult: A Rare Association With Asymptomatic COVID-19

Thrombotic complications have been well described in patients with coronavirus disease 2019 (COVID-19) because of its associated states of hypercoagulability and inflammation. We present a unique case of thrombosis of the femoral artery in a 42-year-old man with asymptomatic COVID-19. This case highlights the need for vigilance when treating patients with COVID-19 to make the necessary diagnostic evaluations and provide appropriate treatment.

Isolated abducens nerve palsy in a patient with asymptomatic SARS-CoV-2 infection

The neuro-ophthalmological complications of SARS-CoV-2 infection are emerging but the spectrum of presentations and pathophysiological mechanism underpinning the association remains to be fully determined. We describe the case of a 44-year-old female who presented with a 12-hour history of diplopia preceded by a mild headache and found to have an isolated right abducens nerve palsy. Initial vital signs were normal but she developed a fever and nasopharyngeal swab confirmed SARS-CoV-2 infection by RT-PCR. All other investigations returned normal including blood tests, chest X-ray, MRI brain and cerebrospinal fluid analysis. She remained systemically well, and there was complete resolution of the abducens palsy and diplopia at two week follow up. In the absence of an alternative underlying cause or risk factors identified, the aetiology was presumed to be microvascular and potentially related to the viral infection. We add to the evolving literature of neuro-ophthalmological associations of SARS-CoV-2, discuss possible causal mechanisms and suggest considering asymptomatic SARS-CoV-2 infection in cases of isolated abducens palsy without clear risk factors.

Improvement in plasma D-dimer level in severe SARS-CoV-2 infection can be an indicator of fibrinolysis suppression: Case reports

RATIONALE

Fibrinolysis shutdown associated with severe thrombotic complications is a recently recognized syndrome that was previously seldom investigated in patients with severe severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. It presents a unique therapeutic dilemma, as anticoagulation with heparin alone is insufficient to address the imbalance in fibrinolysis. And while the use of fibrinolytic agents could limit the disease severity, it is often associated with bleeding complications. There is a need for biomarkers that will guide the timely stratification of patients into those who may benefit from both anticoagulant and fibrinolytic therapies.

PATIENT CONCERNS

All 3 patients presented with shortness of breath along with comorbidities predisposing them to severe SARS-CoV-2 infection. One patient (Patient 3) also suffered from bilateral deep venous thrombosis.

DIAGNOSES

All 3 patients tested positive for SARS-CoV-2 RNA by reverse transcription polymerase chain reaction (RT-PCR) and were eventually diagnosed with respiratory failure necessitating intubation.

INTERVENTIONS

All 3 patients required mechanical ventilation support, 2 of which also required renal replacement therapy. All 3 patients were also placed on anticoagulation therapy.

OUTCOMES

In Patients 1 and 2, the initial D-dimer levels of 0.97 μg/ml fibrinogen equivalent units (FEU) and 0.83 μg/ml FEU were only slightly elevated (normal <0.50 μg/ml FEU). They developed rising D-dimer levels to a peak of 13.21 μg/ml FEU and >20.0 μg/ml FEU, respectively, which dropped to 1.34 μg/ml FEU 8 days later in Patient 1 and to 2.94 μg/ml on hospital day 13 in Patient 2. In Patient 3, the D-dimer level on admission was found to be elevated to >20.00 μg/ml FEU together with imaging evidence of thrombosis. And although he received therapeutic heparin infusion, he still developed pulmonary embolism (PE) and his D-dimer level declined to 5.91 μg/ml FEU. Despite "improvement" in their D-dimer levels, all 3 patients succumbed to multi-system organ failure. On postmortem examination, numerous arterial and venous thromboses of varying ages, many consisting primarily of fibrin, were identified in the lungs of all patients.

LESSONS

High D-dimer levels, with subsequent downtrend correlating with clinical deterioration, seems to be an indicator of fibrinolysis suppression. These findings can help form a hypothesis, as larger cohorts are necessary to demonstrate their reproducibility.

COVID-19: imbalance of multiple systems during infection and importance of therapeutic choice and dosing of cardiac and anti-coagulant therapies

The renin-angiotensin-aldosterone system and its metabolites play an important role in homeostasis of body, especially the cardiovascular system. In this study, we discuss the imbalance of multiple systems during the infection and the importance of therapeutic choice, dosing, and laboratory monitoring of cardiac and anti-coagulant therapies in COVID-19 patients. The crosstalk between angiotensin, kinin-kallikrein system, as well as inflammatory and coagulation systems plays an essential role in COVID-19. Cardiac complications and coagulopathies imply the crosstalks between the mentioned systems. We believe that the blockage of bradykinin can be a good option in the management of COVID-19 and CVD in patients and that supportive treatment of respiratory and cardiologic complications is needed in COVID-19 patients. Ninety-one percent of COVID-19 patients who were admitted to hospital with a prolonged aPTT were positive for lupus anticoagulant, which increases the risk of thrombosis and prolonged aPTT. Therefore, the question that is posed at this juncture is whether it is safe to use the prophylactic dose of heparin particularly in those with elevated D-dimer levels. It should be noted that timing is of high importance in anti-coagulant therapy; therefore, we should consider the level of D-dimer, fibrinogen, drug-drug interactions, and risk factors during thromboprophylaxis administration. Fibrinogen is an independent predictor of resistance to heparin and should be considered before thromboprophylaxis. Alteplase and Futhan might be a good choice to assess the condition of heparin resistance. Finally, the treatment option, dosing, and laboratory monitoring of anticoagulant therapy are critical decisions in COVID-19 patients.

The roles and potential therapeutic implications of C5a in the pathogenesis of COVID-19-associated coagulopathy

Emerging evidence has documented that multisystem organ failure in coronavirus disease 2019 (COVID-19) patients is strongly associated with various coagulopathies. Treatments for COVID-19-associated coagulopathy are still a clinical challenge. An advancement in the knowledge of mechanisms of the excessive or inappropriate activation of the complement cascade involved in the genesis of COVID-19-associated coagulopathy might be a fundamental approach for developing novel classes of anticoagulant drugs. In this context, there is emerging evidence indicating that C5a, a component of the complement system, and its receptors (C5aRs) play a critical role in the genesis of the COVID-19-associated hypercoagulable state. Thus, this review describes the mechanisms by which C5a/C5aR signaling participates in the cascade of events involved in the pathophysiology of COVID-19-associated coagulopathy. Furthermore, it highlights the current possibilities for the development of a novel therapeutic approach for COVID-19 patients that targets C5a/C5aRs signaling.

Mechanisms of thrombosis and cardiovascular complications in COVID-19

BACKGROUND

The novel coronavirus SARS-CoV-2, responsible for the 2019-2020 global (COVID-19) pandemic, is a respiratory virus associated with the development of thromboembolic complications and respiratory failure in severe cases. Increased risk of pulmonary embolism and thrombosis has been identified in COVID-19 patients, alongside accompanying elevations in potential prognostic biomarkers, including D-dimer, IL-6 and cardiac specific troponins. Our aim was to provide a scoping review of the available literature regarding thrombosis risk, other cardiovascular implications, and their biomarkers in COVID-19 to highlight potential disease mechanisms.

METHODS

Authors conducted a literature search in PubMed using MeSH headings "disseminated intravascular coagulation", "pulmonary embolism", "thromb*", "stroke", "myocardial infarction" and "acute lung injury", as well as terms "COVID-19", "SARS-CoV-2", "2019 novel coronavirus" and "2019-nCoV".

RESULTS AND CONCLUSIONS

COVID-19 disease is characterised by the interactions between hyperactive coagulation and complement systems - induced by hyper-inflammatory conditions, resulting in a pro-thrombotic state and diffuse tissue injury. There are several promising prognostic markers of disease severity, with D-dimer the most significant. The presence of thrombocytopenia appears to be a key indicator of patient deterioration. Further research is required to understand the underlying pathophysiology in COVID-19 and its implications in disease progression and patient management. Randomised trials are urgently needed to determine the safety of proposed therapeutic anticoagulation with heparin and the role for anti-platelet agents, such as Ticagrelor, in patient management.

Thromboinflammatory Biomarkers in COVID-19: Systematic Review and Meta-analysis of 17,052 Patients

OBJECTIVE

To evaluate differences in thromboinflammatory biomarkers between patients with severe coronavirus disease 2019 (COVID-19) infection/death and mild infection.

PATIENTS AND METHODS

MEDLINE, Cochrane Central Register of Controlled Trials, EMBASE, EBSCO, Web of Science, and CINAHL databases were searched for studies comparing thromboinflammatory biomarkers in COVID-19 among patients with severe COVID-19 disease or death (severe/nonsurvivors) and those with nonsevere disease or survivors (nonsevere/survivors) from January 1, 2020, through July 11, 2020. Inclusion criteria were (1) hospitalized patients 18 years or older comparing severe/nonsurvivors vs nonsevere/survivors and (2) biomarkers of inflammation and/or thrombosis. A random-effects model was used to estimate the weighted mean difference (WMD) between the 2 groups of COVID-19 severity.

RESULTS

We included 75 studies with 17,052 patients. The severe/nonsurvivor group was older, had a greater proportion of men, and had a higher prevalence of hypertension, diabetes, cardiac or cerebrovascular disease, chronic kidney disease, malignancy, and chronic obstructive pulmonary disease. Thromboinflammatory biomarkers were significantly higher in patients with severe disease, including D-dimer (WMD, 0.60; 95% CI, 0.49 to 0.71; I 2 =83.85%), fibrinogen (WMD, 0.42; 95% CI, 0.18 to 0.67; I 2 =61.88%; P<.001), C-reactive protein (CRP) (WMD, 35.74; 95% CI, 30.16 to 41.31; I 2 =85.27%), high-sensitivity CRP (WMD, 62.68; 95% CI, 45.27 to 80.09; I 2 =0%), interleukin 6 (WMD, 22.81; 95% CI, 17.90 to 27.72; I 2 =90.42%), and ferritin (WMD, 506.15; 95% CI, 356.24 to 656.06; I 2 =52.02%). Moderate to significant heterogeneity was observed for all parameters (I 2 > 25%). Subanalysis based on disease severity, mortality, and geographic region of the studies revealed similar inferences.

CONCLUSION

Thromboinflammatory biomarkers (D-dimer, fibrinogen, CRP, high-sensitivity CRP, ferritin, and interleukin 6) and marker of end-organ damage (high-sensitivity troponin I) are associated with increased severity and mortality in COVID-19 infection.

A possible role for ST2 as prognostic biomarker for COVID-19

COVID-19 is a pandemic illness caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2). It has been estimated that 80% of subject infected are asymptomatic or have mild to moderate symptoms. Differently, in severe cases of COVID-19, cytokine storm, acute respiratory distress syndrome (ARDS), severe systemic inflammatory response and cardiovascular diseases were observed Even if all molecular mechanisms leading to cardiovascular dysfunction in COVID-19 patients remain to be clarified, the evaluation of biomarkers of cardiac injury, stress and inflammation proved to be an excellent tool to identify the COVID-19 patients with worse outcome. However, the number of biomarkers used to manage COVID-19 patients is expected to increase with the increasing knowledge of the pathophysiology of the disease. It is our view that soluble suppressor of tumorigenicity 2 (sST2) can be used as biomarker in COVID-19. sST2 is routinely used as prognostic biomarker in patients with HF. Moreover, high circulating levels of sST2 have also been found in subjects with ARDS, pulmonary fibrosis and sepsis. Keeping in mind these considerations, in this review the possible mechanisms through which the SARS-CoV2 infection could damage the cardiovascular system were summarized and the possible role of sST2 in COVID-19 patients with CVD was discussed.

Interaction between the apelinergic system and ACE2 in the cardiovascular system: therapeutic implications

The apelinergic system is widely expressed and acts through autocrine and paracrine signaling to exert protective effects, including vasodilatory, metabolic, and inotropic effects on the cardiovascular (CV) system. The apelin pathway's dominant physiological role has delineated therapeutic implications for coronary artery disease, heart failure (HF), aortic aneurysm, pulmonary arterial hypertension (PAH), and transplant vasculopathy. Apelin peptides interact with the renin-angiotensin system (RAS) by promoting angiotensin converting enzyme 2 (ACE2) transcription leading to increased ACE2 protein and activity while also antagonizing the effects of angiotensin II (Ang II). Apelin modulation of the RAS by increasing ACE2 action is limited due to its rapid degradation by proteases, including ACE2, neprilysin (NEP), and kallikrein. Apelin peptides are hence tightly regulated in a negative feedback manner by ACE2. Plasma apelin levels are suppressed in pathological conditions, but its diagnostic and prognostic utility requires further clinical exploration. Enhancing the beneficial actions of apelin peptides and ACE2 axes while complementing existing pharmacological blockade of detrimental pathways is an exciting pathway for developing new therapies. In this review, we highlight the interaction between the apelin and ACE2 systems, discuss their pathophysiological roles and potential for treating a wide array of CV diseases (CVDs).

Post-discharge chest CT findings and pulmonary function tests in severe COVID-19 patients

PURPOSE

To evaluate chest computed tomography (CT) and pulmonary function test (PFT) findings in severe COVID-19 patients after discharge and correlate CT pulmonary involvement with PFT results.

METHODS

COVID-19 patients admitted to our hospital between February 25 and May 2, 2020, were retrospectively included according to the following criteria: (a) COVID-19 defined as severe based on the WHO interim guidance (i.e., clinical signs of pneumonia plus respiratory rate > 30 breaths/min, severe respiratory distress, and/or SpO₂ < 90 % on room air); (b) chest radiograph in the acute setting; (c) post-discharge unenhanced chest CT; and (d) post-discharge comprehensive PFT. Imaging findings were retrospectively evaluated in consensus by two readers, and volume of abnormal lung was measured on CT using 3D Slicer software. Differences between demographics, comorbidities, acute radiographic findings, PFT, and post-discharge clinical and laboratory data of patients with normal and abnormal CT findings were assessed by Mann-Whitney or Fisher tests, and the compromised lung volume-PFT association by Pearson correlation after removing possible outliers.

RESULTS

At a median of 105 days from symptom onset, 74/91 (81 %) patients had CT abnormalities. The most common CT pattern was combined ground-glass opacity and reticular pattern (46/74, 62 %) along with architectural distortion (68/74, 92 %) and bronchial dilatation (66/74, 89 %). Compromised lung volume had a median value of 15 % [11-23], was higher in dyspneic patients, and negatively correlated with the percentage of predicted DLCO, VA, and FVC values (r = -0.39, -0.5, and -0.42, respectively). These PFT parameters were significantly lower in patients with CT abnormalities. Impairment of DLCO and KCO was found in 12 (13 %) cases, possibly implying an underlying pulmonary vasculopathy in this subgroup of patients.

CONCLUSIONS

Most severe COVID-19 survivors still had physiologically relevant CT abnormalities about three months after the disease onset, with an impairment of diffusion capacity on PFT. A pulmonary vasculopathy was suggested in a minor proportion of patients.

Limb Ischemia due to Extensive Arterial Thrombosis in the Absence of Venous Occlusion as an Unusual Complication of Critical Illness from COVID-19

There is increasing evidence of a link between the coronavirus disease 2019 (COVID-19) and venous and arterial thrombotic events. Here, we report a 60-year-old male patient with severe COVID-19 who developed extensive arterial thromboses and limb ischemia despite being on therapeutic-dose anticoagulation. While the exact mechanism for such events is unknown, our report highlights the importance of maintaining a high degree of suspicion in critically ill patients. Further research should focus on the mechanistic pathways along with the optimal anticoagulation and/or antithrombotic strategy.

Pathogeny of cerebral venous thrombosis in SARS-Cov-2 infection: Case reports

RATIONALE

Pathogeny of thrombosis in COVID-19 is related to interaction of SARS-Cov-2 with vascular wall through the angiotensin converting enzyme 2 (ACE2) receptor. This induces 2 pathways with immunothrombosis from activated endothelium (cytokine storm, leukocyte and platelet recruitment, and activation of coagulation extrinsic pathway), and rise of angiotensin II levels promoting inflammation. While thrombosis is widely described in COVID-19 patients admitted in intensive care unit, cerebrovascular diseases remains rare, in particular cerebral venous thrombosis (CVT).

PATIENT CONCERNS

We describe 2 cases of women admitted during the spring of 2020 for intracranial hypertension signs, in stroke units in Great-east, a French area particularly affected by COVID-19 pandemia.

DIAGNOSES

Cerebral imaging revealed extended CVT in both cases. The first case described was more serious due to right supratentorial venous infarction with hemorrhagic transformation leading to herniation. Both patients presented typical pneumonia due to SARS-Cov-2 infection, confirmed by reverse transcription polymerase chain reaction on a nasopharyngeal swab in only one.

INTERVENTIONS

The first patient had to undergo decompressive craniectomy, and both patients were treated with anticoagulation therapy.

OUTCOMES

Favorable outcome was observed for 1 patient. Persistent coma, due to bi thalamic infarction, remained for the other with more serious presentation.

LESSONS

CVT, as a serious complication of COVID-19, has to be searched in all patients with intracranial hypertension syndrome. Data about anticoagulation therapy to prevent such serious thrombosis in SARS-Cov-2 infection are lacking, in particular in patients with mild and moderate COVID-19.