Pulmonary Arterial Thrombosis in COVID-19 With Fatal Outcome : Results From a Prospective, Single-Center, Clinicopathologic Case Series

COVID-19 - A vascular disease

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) leads to multi-system dysfunction with emerging evidence suggesting that SARS-CoV-2-mediated endothelial injury is an important effector of the virus. Potential therapies that address vascular system dysfunction and its sequelae may have an important role in treating SARS-CoV-2 infection and its long-lasting effects.

Long-term and short-term immunity to SARS-CoV-2: why it matters

The adaptive immune system, regulated by CD4 T cells, is essential for control of many viral infections. Endemic coronavirus infections generally occur as short-term upper respiratory tract infections which in many cases appear to be cleared before adaptive immunity is fully involved, since adaptive immunity takes approximately 1.5–2 weeks to ramp up the response to a primary infection, or approximately 1 week for a recurrent infection. However, the adaptive immune response to SARS-CoV-2 infection will be critical to full recovery with minimal long-lasting effects, and to either prevention of recurrence of infection or at least reduced severity of symptoms. The detailed kinetics of this infection versus the dynamics of the immune response, including in vaccinated individuals, will largely determine these outcomes.

Is there a role for the ACE2 receptor in SARS-CoV-2 interactions with platelets?

There is an urgent need to understand the underlying mechanisms contributing to thrombotic and inflammatory complications during COVID-19. Data from independent groups have identified that platelets are hyperreactive during COVID-19. Platelet hyperreactivity is accompanied by changes in platelet gene expression, and enhanced interactions between platelets and leukocytes. In some patients, SARS-CoV-2 mRNA has been detected in platelets. Together, this suggests that SARS-CoV-2 may interact with platelets. However, controversy remains on which receptors mediate SARS-CoV-2 platelet interactions. Most, but not all, transcriptomic and proteomic analyses fail to observe the putative SARS-CoV-2 receptor, angiotensin converting enzyme-2, or the cellular serine protease necessary for viral entry, TMPRSS2, on platelets and megakaryocytes. Interestingly, platelets express other known SARS-CoV-2 receptors, which induce similar patterns of activation to those observed when platelets are incubated with SARS-CoV-2. This article explores these findings and discusses ongoing areas of controversy and uncertainty with regard to SARS-CoV-2 platelet interactions.

Lung Histopathology in Coronavirus Disease 2019 as Compared With Severe Acute Respiratory Sydrome and H1N1 Influenza: A Systematic Review

BACKGROUND

Patients with severe coronavirus disease 2019 (COVID-19) have respiratory failure with hypoxemia and acute bilateral pulmonary infiltrates, consistent with ARDS. Respiratory failure in COVID-19 might represent a novel pathologic entity.

RESEARCH QUESTION

How does the lung histopathology described in COVID-19 compare with the lung histopathology described in SARS and H1N1 influenza?

STUDY DESIGN AND METHODS

We conducted a systematic review to characterize the lung histopathologic features of COVID-19 and compare them against findings of other recent viral pandemics, H1N1 influenza and SARS. We systematically searched MEDLINE and PubMed for studies published up to June 24, 2020, using search terms for COVID-19, H1N1 influenza, and SARS with keywords for pathology, biopsy, and autopsy. Using PRISMA-Individual Participant Data guidelines, our systematic review analysis included 26 articles representing 171 COVID-19 patients; 20 articles representing 287 H1N1 patients; and eight articles representing 64 SARS patients.

RESULTS

In COVID-19, acute-phase diffuse alveolar damage (DAD) was reported in 88% of patients, which was similar to the proportion of cases with DAD in both H1N1 (90%) and SARS (98%). Pulmonary microthrombi were reported in 57% of COVID-19 and 58% of SARS patients, as compared with 24% of H1N1 influenza patients.

INTERPRETATION

DAD, the histologic correlate of ARDS, is the predominant histopathologic pattern identified in lung pathology from patients with COVID-19, H1N1 influenza, and SARS. Microthrombi were reported more frequently in both patients with COVID-19 and SARS as compared with H1N1 influenza. Future work is needed to validate this histopathologic finding and, if confirmed, elucidate the mechanistic underpinnings and characterize any associations with clinically important outcomes.

Dooming Phagocyte Responses: Inflammatory Effects of Endogenous Oxidized Phospholipids

Endogenous oxidized phospholipids are produced during tissue stress and are responsible for sustaining inflammatory responses in immune as well as non-immune cells. Their local and systemic production and accumulation is associated with the etiology and progression of several inflammatory diseases, but the molecular mechanisms that underlie the biological activities of these oxidized phospholipids remain elusive. Increasing evidence highlights the ability of these stress mediators to modulate cellular metabolism and pro-inflammatory signaling in phagocytes, such as macrophages and dendritic cells, and to alter the activation and polarization of these cells. Because these immune cells serve a key role in maintaining tissue homeostasis and organ function, understanding how endogenous oxidized lipids reshape phagocyte biology and function is vital for designing clinical tools and interventions for preventing, slowing down, or resolving chronic inflammatory disorders that are driven by phagocyte dysfunction. Here, we discuss the metabolic and signaling processes elicited by endogenous oxidized lipids and outline new hypotheses and models to elucidate the impact of these lipids on phagocytes and inflammation.

Pathophysiological mechanisms of liver injury in COVID-19

The recent outbreak of coronavirus disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has resulted in a world-wide pandemic. Disseminated lung injury with the development of acute respiratory distress syndrome (ARDS) is the main cause of mortality in COVID-19. Although liver failure does not seem to occur in the absence of pre-existing liver disease, hepatic involvement in COVID-19 may correlate with overall disease severity and serve as a prognostic factor for the development of ARDS. The spectrum of liver injury in COVID-19 may range from direct infection by SARS-CoV-2, indirect involvement by systemic inflammation, hypoxic changes, iatrogenic causes such as drugs and ventilation to exacerbation of underlying liver disease. This concise review discusses the potential pathophysiological mechanisms for SARS-CoV-2 hepatic tropism as well as acute and possibly long-term liver injury in COVID-19.

Pulmonary thrombosis in Covid-19: before, during and after hospital admission

Disordered coagulation, endothelial dysfunction, dehydration and immobility contribute to a substantially elevated risk of deep venous thrombosis, pulmonary embolism (PE) and systemic thrombosis in coronavirus disease 2019 (Covid-19). We evaluated the prevalence of pulmonary thrombosis and reported RV (right ventricular) dilatation/dysfunction associated with Covid-19 in a tertiary referral Covid-19 centre. Of 370 patients, positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), 39 patients (mean age 62.3 ± 15 years, 56% male) underwent computed tomography pulmonary angiography (CTPA), due to increasing oxygen requirements or refractory hypoxia, not improving on oxygen, very elevated D-dimer or tachycardia disproportionate to clinical condition. Thrombosis in the pulmonary vasculature was found in 18 (46.2%) patients. However, pulmonary thrombosis did not predict survival (46.2% survivors vs 41.7% non-survivors, p = 0.796), but RV dilatation was less frequent among survivors (11.5% survivors vs 58.3% non-survivors, p = 0.002). Over the following month, we observed four Covid-19 patients, who were admitted with high and intermediate-high risk PE, and we treated them with UACTD (ultrasound-assisted catheter-directed thrombolysis), and four further patients, who were admitted with PE up to 4 weeks after recovery from Covid-19. Finally, we observed a case of RV dysfunction and pre-capillary pulmonary hypertension, associated with Covid-19 extensive lung disease. We demonstrated that pulmonary thrombosis is common in association with Covid-19. Also, the thrombotic risk in the pulmonary vasculature is present before and during hospital admission, and continues at least up to four weeks after discharge, and we present UACTD for high and intermediate-high risk PE management in Covid-19 patients.

Beyond the clot: perfusion imaging of the pulmonary vasculature after COVID-19

A compelling body of evidence points to pulmonary thrombosis and thromboembolism as a key feature of COVID-19. As the pandemic spread across the globe over the past few months, a timely call to arms was issued by a team of clinicians to consider the prospect of long-lasting pulmonary fibrotic damage and plan for structured follow-up. However, the component of post-thrombotic sequelae has been less widely considered. Although the long-term outcomes of COVID-19 are not known, should pulmonary vascular sequelae prove to be clinically significant, these have the potential to become a public health problem. In this Personal View, we propose a proactive follow-up strategy to evaluate residual clot burden, small vessel injury, and potential haemodynamic sequelae. A nuanced and physiological approach to follow-up imaging that looks beyond the clot, at the state of perfusion of lung tissue, is proposed as a key triage tool, with the potential to inform therapeutic strategies.

Obesity, malnutrition, and trace element deficiency in the coronavirus disease (COVID-19) pandemic: An overview

The world is currently facing the coronavirus disease (COVID-19) pandemic which places great pressure on health care systems and workers, often presents with severe clinical features, and sometimes requires admission into intensive care units. Derangements in nutritional status, both for obesity and malnutrition, are relevant for the clinical outcome in acute illness. Systemic inflammation, immune system impairment, sarcopenia, and preexisting associated conditions, such as respiratory, cardiovascular, and metabolic diseases related to obesity, could act as crucial factors linking nutritional status and the course and outcome of COVID-19. Nevertheless, vitamins and trace elements play an essential role in modulating immune response and inflammatory status. Overall, evaluation of the patient's nutritional status is not negligible for its implications on susceptibility, course, severity, and responsiveness to therapies, in order to perform a tailored nutritional intervention as an integral part of the treatment of patients with COVID-19. The aim of this study was to review the current data on the relevance of nutritional status, including trace elements and vitamin status, in influencing the course and outcome of the disease 3 mo after the World Health Organization's declaration of COVID-19 as a pandemic.

Coronavirus Disease 2019-Associated Coagulopathy

Patients with the severe form of coronavirus disease 2019 (COVID-19) have been frequently found to suffer from both arterial and venous thrombotic events due to the perpetuation of a hypercoagulable state. This phenomenon, termed COVID-19-associated coagulopathy, is now considered a major component of the pathophysiology of this novel infectious disease, leading to widespread thrombosis. While at first, the vascular insults may be limited to the pulmonary microvasculature, as the disease progresses, systemic involvement occurs, culminating in distant organ thrombosis and multiorgan dysfunction syndrome. In this review article, we discuss recent insights into the pathophysiologic mechanisms of COVID-19-associated coagulopathy and review the clinical, histopathologic, and laboratory evidence, which leads us to conclude that COVID-19 is both a pulmonary and vascular disorder.

The pulmonary pathology of COVID-19

The lung is the main affected organ in severe coronavirus disease 2019 (COVID-19) caused by the novel coronavirus SARS-CoV-2, and lung damage is the leading cause of death in the vast majority of patients. Mainly based on results obtained by autopsies, the seminal features of fatal COVID-19 have been described by many groups worldwide. Early changes encompass edema, epithelial damage, and capillaritis/endothelialitis, frequently combined with microthrombosis. Subsequently, patients with manifest respiratory insufficiency exhibit exudative diffuse alveolar damage (DAD) with hyaline membrane formation and pneumocyte type 2 hyperplasia, variably complicated by superinfection, which may progress to organizing/fibrotic stage DAD. These features, however, are not specific for COVID-19 and can be found in other disorders including viral infections. Clinically, the early disease stage of severe COVID-19 is characterized by high viral load, lymphopenia, massive secretion of pro-inflammatory cytokines and hypercoagulability, documented by elevated D-dimers and an increased frequency of thrombotic and thromboembolic events, whereas virus loads and cytokine levels tend to decrease in late disease stages, when tissue repair including angiogenesis prevails. The present review describes the spectrum of lung pathology based on the current literature and the authors' personal experience derived from clinical autopsies, and tries to summarize our current understanding and open questions of the pathophysiology of severe pulmonary COVID-19.

Prevalence of liver injury in 445 patients with Corona Virus Disease-19-Single-centre experience from southern India

BACKGROUND

Abnormal liver function tests (LFT) are common in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and vary from 15% to 53%. There are scanty data  from India on the prevalence of liver injury in corona virus disease 2019 (COVID-19) patients.

METHODS

We did this retrospective study in a tertiary care hospital, Chennai, India. Patients aged >18 years admitted with COVID-19 from May 1, 2020, to May 31, 2020, were included. We noted the demographic details, symptoms at presentation, history of pre-existing illnesses, and laboratory tests. We also recorded the patient's clinical course and outcome.

RESULTS

We took 445 patients for final analysis. Aspartate transaminase (AST) was borderline elevated in 47.5%, mildly elevated in 11.2%, moderately elevated in 2% and severely in 0.7%. Alanine transaminase (ALT) was borderline elevated in 28.7%, mildly elevated in 11.4%, and moderately elevated in 1.3%. Bilirubin and alkaline phosphatase were abnormal in only 19 (4.2%) and 15 (3.3%) patients, respectively. Patients with abnormal LFT were more likely to be symptomatic (90.3% vs. 80.6%, p 0.002). Respiratory symptoms (43.5% vs. 29.7%) and loose stools (11.4% vs. 3.4%) were also more common among them. Patients with abnormal LFT were more likely to have severe disease (25.2% vs. 13.6%, p value 0.003) and mortality (8.8% vs. 0.7%).

CONCLUSION

Liver test abnormalities were widespread in patients with COVID-19. Most of the patients had borderline or mild transaminase elevation. Despite only mild changes, patients with abnormal LFT were more likely to be symptomatic and had more severe disease and mortality.

Pulmonary embolism in patients with COVID-19 and value of D-dimer assessment: a meta-analysis

PURPOSE

To investigate, in a meta-analysis, the frequency of pulmonary embolism (PE) in patients with COVID-19 and whether D-dimer assessment may be useful to select patients for computed tomography pulmonary angiography (CTPA).

METHODS

A systematic literature search was performed for original studies which reported the frequency of PE on CTPA in patients with COVID-19. The frequency of PE, the location of PE, and the standardized mean difference (SMD) of D-dimer levels between patients with and without PE were pooled by random effects models.

RESULTS

Seventy-one studies were included. Pooled frequencies of PE in patients with COVID-19 at the emergency department (ED), general wards, and intensive care unit (ICU) were 17.9% (95% CI: 12.0-23.8%), 23.9% (95% CI: 15.2-32.7%), and 48.6% (95% CI: 41.0-56.1%), respectively. PE was more commonly located in peripheral than in main pulmonary arteries (pooled frequency of 65.3% [95% CI: 60.0-70.1%] vs. 32.9% [95% CI: 26.7-39.0%]; OR = 3.540 [95% CI: 2.308-5.431%]). Patients with PE had significantly higher D-dimer levels (pooled SMD of 1.096 [95% CI, 0.844-1.349]). D-dimer cutoff levels which have been used to identify patients with PE varied between 1000 and 4800 μg/L.

CONCLUSION

The frequency of PE in patients with COVID-19 is highest in the ICU, followed by general wards and the ED. PE in COVID-19 is more commonly located in peripheral than in central pulmonary arteries, which suggests local thrombosis to play a major role. D-dimer assessment may help to select patients with COVID-19 for CTPA, using D-dimer cutoff levels of at least 1000 μg/L.

KEY POINTS

• The frequency of PE in patients with COVID-19 is highest in the ICU, followed by general wards and the ED. • PE in COVID-19 is more commonly located in peripheral than in central pulmonary arteries. • D-dimer levels are significantly higher in patients with COVID-19 who have PE.

Angiotensin-converting enzyme 2 (ACE2): COVID 19 gate way to multiple organ failure syndromes

BACKGROUND

Globally, the current medical emergency for novel coronavirus 2019 (COVID-19) leads to respiratory distress syndrome and death.

PURPOSE

This review highlighted the effect of COVID-19 on systemic multiple organ failure syndromes. This review is intended to fill a gap in information about human physiological response to COVID-19 infections. This review may shed some light on other potential mechanisms and approaches in COVID -19 infections towards systemic multiorgan failure syndromes.

FINDING

SARS-CoV-2 intervened mainly in the lung with progression to pneumonia and acute respiratory distress syndrome (ARDS) via the angiotensin-converting enzyme 2(ACE2) receptor. Depending on the viral load, infection spread through the ACE2 receptor further to various organs such as heart, liver, kidney, brain, endothelium, GIT, immune cell, and RBC (thromboembolism). This may be aggravated by cytokine storm with the extensive release of proinflammatory cytokines from the deregulating immune system.

CONCLUSION

The widespread and vicious combinations of cytokines with organ crosstalk contribute to systemic hyper inflammation and ultimately lead to multiple organ dysfunction (Fig. 1). This comprehensive study comprises various manifestations of different organs in COVID-19 and may assist the clinicians and scientists pertaining to a broad approach to fight COVID 19.

COVID-19 and Sepsis Are Associated With Different Abnormalities in Plasma Procoagulant and Fibrinolytic Activity

OBJECTIVE

Coronavirus disease 2019 (COVID-19) is associated with derangement in biomarkers of coagulation and endothelial function and has been likened to the coagulopathy of sepsis. However, clinical laboratory metrics suggest key differences in these pathologies. We sought to determine whether plasma coagulation and fibrinolytic potential in patients with COVID-19 differ compared with healthy donors and critically ill patients with sepsis. Approach and Results: We performed comparative studies on plasmas from a single-center, cross-sectional observational study of 99 hospitalized patients (46 with COVID-19 and 53 with sepsis) and 18 healthy donors. We measured biomarkers of endogenous coagulation and fibrinolytic activity by immunoassays, thrombin, and plasmin generation potential by fluorescence and fibrin formation and lysis by turbidity. Compared with healthy donors, patients with COVID-19 or sepsis both had elevated fibrinogen, d-dimer, soluble TM (thrombomodulin), and plasmin-antiplasmin complexes. Patients with COVID-19 had increased thrombin generation potential despite prophylactic anticoagulation, whereas patients with sepsis did not. Plasma from patients with COVID-19 also had increased endogenous plasmin potential, whereas patients with sepsis showed delayed plasmin generation. The collective perturbations in plasma thrombin and plasmin generation permitted enhanced fibrin formation in both COVID-19 and sepsis. Unexpectedly, the lag times to thrombin, plasmin, and fibrin formation were prolonged with increased disease severity in COVID-19, suggesting a loss of coagulation-initiating mechanisms accompanies severe COVID-19.

CONCLUSIONS

Both COVID-19 and sepsis are associated with endogenous activation of coagulation and fibrinolysis, but these diseases differently impact plasma procoagulant and fibrinolytic potential. Dysregulation of procoagulant and fibrinolytic pathways may uniquely contribute to the pathophysiology of COVID-19 and sepsis.

COVID-19 autopsies: Procedure, technical aspects and cause of fatal course. Experiences from a single-center

Autopsies on COVID-19 have provided deep insights into a novel disease with unpredictable and potentially fatal outcome. A standardized autopsy procedure preferably with an in-situ technique and systematic tissue processing is important. Strict safety measures include personal protective equipment with a standardized protocol for dressing and undressing, usage of FFP-3 masks and minimization of aerosol production. The use of an airborne infection isolation (AIIR) room is preferred. Viral RNA analysis using swabs from throat, both lungs and other organs provides information on cross-organ viral dynamics. To correctly determine the full extent of pathological organ changes an adequate processing procedure is of the utmost importance. Systematic dissection and processing of the lungs revealed pulmonary infarction caused by thrombosis and thromboembolism and bacterial bronchopneumonia as the most frequent cause of death. Fungal pneumonia (aspergillus) was found in one case. The quality of the tissue was sufficient for histopathological and immunohistochemistry analyses in all cases. Viral RNA from throat or lung swabs was detectable post mortem in 89 % of the cases and could also be detected from paraffin-embedded tissue by real-time PCR. Complete COVID-19 autopsies including extensive histopathological studies and viral RNA analysis require approximately three times more human and technical resources and time compared to standard non-COVID autopsies. Autopsies on COVID-19 are feasible, present a manageable risk, while following a strict protocol, and provide novel insights into disease pathogenesis and the clinician with important feedback.

High lipasemia is frequent in Covid-19 associated acute respiratory distress syndrome

BACKGROUND

Covid-19 is a rapidly spreading viral disease that can cause severe acute respiratory distress syndrome (ARDS). Besides the lungs it can also affect other organs like the heart or the liver. Whether there is a pancreatic manifestation as well is currently unclear.

METHODS

and aims: We prospectively collected patient information of patients with Covid-19 associated ARDS in a registry (COvid Registry REChts der Isar intensive care Trial - CORRECT) and analyzed this patient cohort for signs of acute pancreatitis (e.g. lipase activity >3 times the upper limit).

RESULTS

12/38 (31.6%) patients with Covid-19 associated ARDS had a serum lipase activity >180 U/l. Median lipase activity was 422 U/l (186-1127). No patient showed typical findings of acute pancreatitis on imaging studies. On hemodynamic monitoring no patient had signs of intravascular fluid demand regarding MAP, GEDVI and therapy with vasopressors. To avoid worsening respiratory function no treatment with crystalloids was initiated. Lipasemia was not explained by gastroenteritis or renal insufficiency, occurred before as well as after viral clearance and 16.1 ± 6.0 days after the first symptoms. No patient developed severe acute pancreatitis during the follow up period of 35.8 ± 8.3 days.

CONCLUSION

High lipasemia without typical signs of acute pancreatitis is a frequent finding in severe Covid-19 associated ARDS. Considering the markedly high levels of serum lipase activity, we think impaired microcirculation in severely ill patients can explain this finding rather than extra-pancreatic co-morbidities (UTN: DRKS00021612).

COVID-19 Infection: Viral Macro- and Micro-Vascular Coagulopathy and Thromboembolism/Prophylactic and Therapeutic Management

Coronavirus-2019 (COVID-19) predisposes patients to arterial and venous thrombosis commonly complicating the clinical course of hospitalized patients and attributed to the inflammatory state, endothelial dysfunction, platelet activation and blood stasis. This viral coagulopathy may occur despite thromboprophylaxis and raises mortality; the risk appears highest among critically ill inpatients monitored in the intensive care unit. The prevalence of venous thromboembolism in COVID-19 patients has been reported to reach ∼10-35%, while autopsies raise it to nearly 60%. The most common thrombotic complication is pulmonary embolism, which though may occur in the absence of a recognizable deep venous thrombosis and may be due to pulmonary arterial thrombosis rather than embolism, resulting in thrombotic occlusion of small- to mid-sized pulmonary arteries and subsequent infarction of lung parenchyma. This micro-thrombotic pattern seems more specific for COVID-19 and is associated with an intense immuno-inflammatory reaction that results in diffuse occlusive thrombotic micro-angiopathy with alveolar damage and vascular angiogenesis. Furthermore, thrombosis has also been observed in various arterial sites, including coronary, cerebral and peripheral arteries. Biomarkers related to coagulation, platelet activation and inflammation have been suggested as useful diagnostic and prognostic tools for COVID-19-associated coagulopathy; among them, D-dimer remains a key biomarker employed in clinical practice. Various medical societies have issued guidelines or consensus statements regarding thromboprophylaxis and treatment of these thrombotic complications specifically adapted to COVID-19 patients. All these issues are detailed in this review, data from meta-analyses and current guidelines are tabulated, while the relevant mechanisms of this virus-associated coagulopathy are pictorially illustrated.

Potential Therapeutic Benefits of Dipyridamole in COVID-19 Patients

BACKGROUND

COVID-19 pandemic is caused by coronavirus also known as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The viral infection continues to impact the globe with no vaccine to prevent the infection or highly effective therapeutics to treat the millions of infected people around the world. The disease starts as a respiratory infection, yet it may also be associated with a hypercoagulable state, severe inflammation owing to excessive cytokines production, and a potentially significant oxidative stress. The disease may progress to multiorgan failure and eventually death.

OBJECTIVE

In this article, we summarize the potential of dipyridamole as an adjunct therapy for COVID-19.

METHODS

We reviewed the literature describing the biological activities of dipyridamole in various settings of testing. Data were retrieved from PubMed, SciFinder-CAS, and Web of Science. The review concisely covered relevant studies starting from 1977.

RESULTS

Dipyridamole is an approved antiplatelet drug, that has been used to prevent stroke, among other indications. Besides its antithrombotic activity, the literature indicates that dipyridamole also promotes a host of other biological activities including antiviral, anti-inflammatory, and antioxidant ones.

CONCLUSION

Dipyridamole may substantially help improve the clinical outcomes of COVID-19 treatment. The pharmacokinetics profile of the drug is well established which makes it easier to design an appropriate therapeutic course. The drug is also generally safe, affordable, and available worldwide. Initial clinical trials have shown a substantial promise for dipyridamole in treating critically ill COVID-19 patients, yet larger randomized and controlled trials are needed to confirm this promise.

High prevalence of hepatic steatosis and vascular thrombosis in COVID-19: A systematic review and meta-analysis of autopsy data

BACKGROUND

Coronavirus disease 2019 (COVID-19) disease can frequently affect the liver. Data on hepatic histopathological findings in COVID-19 is scarce.

AIM

To characterize hepatic pathological findings in patients with COVID-19.

METHODS

We conducted a systematic review with meta-analysis registered on PROSPERO (CRD42020192813), following PRISMA guidelines. Eligible trials were those including patients of any age and COVID-19 diagnosis based on a molecular test. Histopathological reports from deceased COVID-19 patients undergoing autopsy or liver biopsy were reviewed. Articles including less than ten patients were excluded. Proportions were pooled using random-effects models. Q statistic and I² were used to assess heterogeneity and levels of evidence, respectively.

RESULTS

We identified 18 studies from 7 countries; all were case reports and case series from autopsies. All the patients were over 15 years old, and 67.2% were male. We performed a meta-analysis of 5 studies, including 116 patients. Pooled prevalence estimates of liver histopathological findings were hepatic steatosis 55.1% [95% confidence interval (CI): 46.2-63.8], congestion of hepatic sinuses 34.7% (95%CI: 7.9-68.4), vascular thrombosis 29.4% (95%CI: 0.4-87.2), fibrosis 20.5% (95%CI: 0.6-57.9), Kupffer cell hyperplasia 13.5% (95%CI: 0.6-54.3), portal inflammation 13.2% (95%CI: 0.1-48.8), and lobular inflammation 11.6% (95%CI: 0.3-35.7). We also identified the presence of venous outflow obstruction, phlebosclerosis of the portal vein, herniated portal vein, periportal abnormal vessels, hemophagocytosis, and necrosis.

CONCLUSION

We found a high prevalence of hepatic steatosis and vascular thrombosis as major histological liver features. Other frequent findings included portal and lobular inflammation and Kupffer cell hyperplasia or proliferation. Further studies are needed to establish the mechanisms and implications of these findings.

Severe SARS-CoV-2 patients develop a higher specific T-cell response

OBJECTIVES

Assessment of the adaptive immune response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is crucial for studying long-term immunity and vaccine strategies. We quantified IFNγ-secreting T cells reactive against the main viral SARS-CoV-2 antigens using a standardised enzyme-linked immunospot assay (ELISpot).

METHODS

Overlapping peptide pools built from the sequences of M, N and S viral proteins and a mix (MNS) were used as antigens. Using IFNγ T-CoV-Spot assay, we assessed T-cell and antibody responses in mild, moderate and severe SARS-CoV-2 patients and in control samples collected before the outbreak.

RESULTS

Specific T cells were assessed in 60 consecutive patients (mild, n = 26; moderate, n = 10; and severe patients, n = 24) during their follow-up (median time from symptom onset [interquartile range]: 36 days [28;53]). T cells against M, N and S peptide pools were detected in n = 60 (100%), n = 56 (93.3%), n = 55 patients (91.7%), respectively. Using the MNS mix, IFNγ T-CoV-Spot assay showed a specificity of 96.7% (95% CI, 88.5-99.6%) and a specificity of 90.3% (75.2-98.0%). The frequency of reactive T cells observed with M, S and MNS mix pools correlated with severity and with levels of anti-S1 and anti-RBD serum antibodies.

CONCLUSION

IFNγ T-CoV-Spot assay is a reliable method to explore specific T cells in large cohorts of patients. This test may become a useful tool to assess the long-lived memory T-cell response after vaccination. Our study demonstrates that SARS-CoV-2 patients developing a severe disease achieve a higher adaptive immune response.

Hypercoagulopathy in Severe COVID-19: Implications for Acute Care

COVID-19 was first described in late 2019 and has since developed into a pandemic affecting more than 21 million people worldwide. Of particular relevance for acute care is the occurrence of COVID-19-associated coagulopathy (CAC), which is characterised by hypercoagulability, immunothrombosis and venous thromboembolism, and contributes to hypoxia in a significant proportion of patients. This review describes diagnosis and treatment of CAC in the emergency department and in intensive care. We summarise the pathological mechanisms and common complications of CAC such as pulmonary thrombosis and venous thromboembolic events and discuss current strategies for thromboprophylaxis and therapeutic anti-coagulation in the acute care setting.

Coagulopathy: Another side effect of coronavirus infection

Recently, coronavirus disease 2019 (COVID-19) has been considered as a major health problem around the globe. This severe acute respiratory syndrome has a bunch of features, such as high transmission rate, which are adding to its importance. Overcoming this disease relies on a complete understanding of the viral structure, receptors, at-risk cells or tissues, and pathogenesis. Currently, researches have shown that besides the lack of a proper anti-viral therapeutic method, complications provided by this virus are also standing in the way of decreasing its mortality rate. One of these complications is believed to be a hematologic manifestation. Commonly, three kinds of coagulopathies are detected in COVID-19 patients: disseminated intravascular coagulation (DIC), pulmonary embolism (PE), and deep vein thrombosis (DVT). In this paper, we have reviewed the relation between these conditions and coronavirus-related diseases pathogenesis, severity, and mortality rate.

Barotrauma in mechanically ventilated patients with Coronavirus disease 2019: a survey of 38 hospitals in Lombardy, Italy

BACKGROUND

The aim was to describe the incidence and risk factors of barotrauma in patients with the Coronavirus disease 2019 (COVID-19) on invasive mechanical ventilation, during the outbreak in our region (Lombardy, Italy).

METHODS

The study was an electronic survey open from March 27^th to May 2^nd, 2020. Patients with COVID-19 who developed barotrauma while on invasive mechanical ventilation from 61 hospitals of the COVID-19 Lombardy Intensive Care Unit network were involved.

RESULTS

The response rate was 38/61 (62%). The incidence of barotrauma was 145/2041 (7.1%; 95%-CI: 6.1-8.3%). Only a few cases occurred with ventilatory settings that may be considered non-protective such as a plateau airway pressure >35 cmH<inf>2</inf>O (2/113 [2%]), a driving airway pressure >15 cmH<inf>2</inf>O (30/113 [27%]), or a tidal volume >8 mL/kg of ideal body weight and a plateau airway pressure >30 cmH<inf>2</inf>O (12/134 [9%]).

CONCLUSIONS

Within the limits of a survey, patients with COVID-19 might be at high risk for barotrauma during invasive (and allegedly lung-protective) mechanical ventilation.

COVID-19 and thrombosis: From bench to bedside

Coronavirus disease of 2019 (COVID-19) is the respiratory viral infection caused by the coronavirus SARS-CoV2 (Severe Acute Respiratory Syndrome Coronavirus 2). Despite being a respiratory illness, COVID-19 is found to increase the risk of venous and arterial thromboembolic events. Indeed, the link between COVID-19 and thrombosis is attracting attention from the broad scientific community. In this review we will analyze the current available knowledge of the association between COVID-19 and thrombosis. We will highlight mechanisms at both molecular and cellular levels that may explain this association. In addition, the article will review the antithrombotic properties of agents currently utilized or being studied in COVID-19 management. Finally, we will discuss current professional association guidance on prevention and treatment of thromboembolism associated with COVID-19.

Blood molecular markers associated with COVID-19 immunopathology and multi-organ damage

COVID-19 is characterized by dysregulated immune responses, metabolic dysfunction and adverse effects on the function of multiple organs. To understand host responses to COVID-19 pathophysiology, we combined transcriptomics, proteomics, and metabolomics to identify molecular markers in peripheral blood and plasma samples of 66 COVID-19-infected patients experiencing a range of disease severities and 17 healthy controls. A large number of expressed genes, proteins, metabolites, and extracellular RNAs (exRNAs) exhibit strong associations with various clinical parameters. Multiple sets of tissue-specific proteins and exRNAs varied significantly in both mild and severe patients suggesting a potential impact on tissue function. Chronic activation of neutrophils, IFN-I signaling, and a high level of inflammatory cytokines were observed in patients with severe disease progression. In contrast, COVID-19-infected patients experiencing milder disease symptoms showed robust T-cell responses. Finally, we identified genes, proteins, and exRNAs as potential biomarkers that might assist in predicting the prognosis of SARS-CoV-2 infection. These data refine our understanding of the pathophysiology and clinical progress of COVID-19.

Potential Mechanisms for Traditional Chinese Medicine in Treating Airway Mucus Hypersecretion Associated With Coronavirus Disease 2019

Background

The rapid development of coronavirus disease 2019 (COVID-19) pandemic has become a great threat to global health. Its mortality is associated with inflammation-related airway mucus hypersecretion and dysfunction of expectoration, and the subsequent mucus blockage of the bronchioles at critical stage is attributed to hypoxemia, complications, and even death. Traditional Chinese medicine (TCM) has rich experience in expectorant, including treatment of COVID-19 patients with airway mucus dysfunction, yet little is known about the mechanisms. This study is aiming to explore the potential biological basis of TCM herbal expectorant for treating COVID-19.

Objective

To get core herbs with high used frequency applications in the actions of expectoration by using association rule algorithm and to investigate the multitarget mechanisms of core herbs in expectorant formulae for COVID-19 therapies.

Methods

Forty prescriptions for expectorant were retrieved from TCM Formulae. The ingredient compounds and targets of core herbs were collected from the TCMSP database, Gene-Cards, and NCBI. The protein interaction network (PPI) was constructed by SRING, and the network analysis was done by Cytoscape software. Bioconductor was applied for functional enrichment analysis of targets.

Results

The core herbs of expectorant could regulate core pathways (MAP kinase activity, cytokine receptor binding, G-protein-coupled receptor binding, etc.) via interactions of ingredients (glycyrol, citromitin, etc.) on mucin family to eliminate phlegm.

Conclusion

TCM herbal expectorant could regulate MAPK and cytokine-related pathways, thereby modulating Mucin-family to affect mucus generation and clearance and eventually retarding the deterioration of COVID-19 disease.

Transcriptional profiling of leukocytes in critically ill COVID19 patients: implications for interferon response and coagulation

BACKGROUND

COVID19 is caused by the SARS-CoV-2 virus and has been associated with severe inflammation leading to organ dysfunction and mortality. Our aim was to profile the transcriptome in leukocytes from critically ill patients positive for COVID19 compared to those negative for COVID19 to better understand the COVID19-associated host response. For these studies, all patients admitted to our tertiary care intensive care unit (ICU) suspected of being infected with SARS-CoV-2, using standardized hospital screening methodologies, had blood samples collected at the time of admission to the ICU. Transcriptome profiling of leukocytes via ribonucleic acid sequencing (RNAseq) was then performed and differentially expressed genes as well as significantly enriched gene sets were identified.

RESULTS

We enrolled seven COVID19 + (PCR positive, 2 SARS-CoV-2 genes) and seven age- and sex-matched COVID19- (PCR negative) control ICU patients. Cohorts were well-balanced with the exception that COVID19- patients had significantly higher total white blood cell counts and circulating neutrophils and COVID19 + patients were more likely to suffer bilateral pneumonia. The mortality rate for this cohort of COVID19 + ICU patients was 29%. As indicated by both single-gene based and gene set (GSEA) approaches, the major disease-specific transcriptional responses of leukocytes in critically ill COVID19 + ICU patients were: (i) a robust overrepresentation of interferon-related gene expression; (ii) a marked decrease in the transcriptional level of genes contributing to general protein synthesis and bioenergy metabolism; and (iii) the dysregulated expression of genes associated with coagulation, platelet function, complement activation, and tumour necrosis factor/interleukin 6 signalling.

CONCLUSIONS

Our findings demonstrate that critically ill COVID19 + patients on day 1 of admission to the ICU display a unique leukocyte transcriptional profile that distinguishes them from COVID19- patients, providing guidance for future targeted studies exploring novel prognostic and therapeutic aspects of COVID19.

Therapeutic plasma exchange for COVID-19-associated hyperviscosity

Background

Recent data suggests an association between blood hyperviscosity and both propensity for thrombosis and disease severity in patients with COVID‐19. This raises the possibility that increased viscosity may contribute to endothelial damage and multiorgan failure in COVID‐19, and that therapeutic plasma exchange (TPE) to decrease viscosity may improve patient outcomes.

Here we sought to share our experience using TPE in the first 6 patients treated for COVID‐19‐associated hyperviscosity.

Study Design and Methods

Six critically ill COVID‐19 patients with plasma viscosity levels ranging from 2.6 to 4.2 centipoise (cP; normal range, 1.4‐1.8 cP) underwent daily TPE for 2‐3 treatments.

Results

TPE decreased plasma viscosity in all six patients (Pre‐TPE median 3.75 cP, range 2.6‐4.2 cP; Post‐TPE median 1.6 cP, range 1.5‐1.9 cP). TPE also decreased fibrinogen levels in all five patients for whom results were available (Pre‐TPE median 739 mg/dL, range 601‐1188 mg/dL; Post‐TPE median 359 mg/dL, range 235‐461 mg/dL); D‐dimer levels in all six patients (Pre‐TPE median 5921 ng/mL, range 1134‐60 000 ng/mL; Post‐TPE median 4893 ng/mL, range 620‐7518 ng/mL); and CRP levels in five of six patients (Pre‐TPE median 292 mg/L, range 136‐329 mg/L; Post‐TPE median 84 mg/L, range 31‐211 mg/L). While the two sickest patients died, significant improvement in clinical status was observed in four of six patients shortly after TPE.

Conclusions

This series demonstrates the utility of TPE to rapidly correct increased blood viscosity in patients with COVID‐19‐associated hyperviscosity. Large randomized trials are needed to determine whether TPE may improve clinical outcomes for patients with COVID‐19.

[Organ changes found by postmortem examination in COVID-19 patients]

The postmortem study results presented in 20 sources of literature on 186 COVID-19 patients were analyzed. Pathological changes were noted in multiple organs, by involving predominantly the respiratory, circulatory, and excretory systems. The changes in the lungs were characterized by an increase in organ weight (59.3%), a dark red color of the parenchyma (47.4%), compaction of lung tissue (56%), and signs of lung congestion (37.3%). The histological characteristics found during postmortem lung tissue examination, which were indicative of diffuse alveolar damage, were proliferation of type II alveolocytes in 65.2% of cases, the appearance of hyaline membranes lining the alveoli in 64.4%, and interstitial edema in 54.2%. In the analyzed sources, 22% of cases were noticed to have severe thrombosis and pulmonary artery branch embolism that was associated with lower extremity deep vein thrombosis. In all the sources of literature, acute tubular necrosis, tubular luminal dilatation, and interstitial edema were detected in the kidneys.

Pandemic Perspective: Commonalities Between COVID-19 and Cardio-Oncology

Overlapping commonalities between coronavirus disease of 2019 (COVID-19) and cardio-oncology regarding cardiovascular toxicities (CVT), pathophysiology, and pharmacology are special topics emerging during the pandemic. In this perspective, we consider an array of CVT common to both COVID-19 and cardio-oncology, including cardiomyopathy, ischemia, conduction abnormalities, myopericarditis, and right ventricular (RV) failure. We also emphasize the higher risk of severe COVID-19 illness in patients with cardiovascular disease (CVD) or its risk factors or cancer. We explore commonalities in the underlying pathophysiology observed in COVID-19 and cardio-oncology, including inflammation, cytokine release, the renin-angiotensin-aldosterone-system, coagulopathy, microthrombosis, and endothelial dysfunction. In addition, we examine common pharmacologic management strategies that have been elucidated for CVT from COVID-19 and various cancer therapies. The use of corticosteroids, as well as antibodies and inhibitors of various molecules mediating inflammation and cytokine release syndrome, are discussed. The impact of angiotensin converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) is also addressed, since these drugs are used in cardio-oncology and have received considerable attention during the COVID-19 pandemic, since the culprit virus enters human cells via the angiotensin converting enzyme 2 (ACE2) receptor. There are therefore several areas of overlap, similarity, and interaction in the toxicity, pathophysiology, and pharmacology profiles in COVID-19 and cardio-oncology syndromes. Learning more about either will likely provide some level of insight into both. We discuss each of these topics in this viewpoint, as well as what we foresee as evolving future directions to consider in cardio-oncology during the pandemic and beyond. Finally, we highlight commonalities in health disparities in COVID-19 and cardio-oncology and encourage continued development and implementation of innovative solutions to improve equity in health and healing.

Thrombosis of pulmonary vasculature despite anticoagulation and thrombolysis: The findings from seven autopsies

Background

Venous thromboembolism (VTE) with the prevalence of pulmonary microcirculatory thrombosis is considered a common complication of novel coronavirus disease (COVID-19) that develops despite anticoagulation.

Methods

The clinical course of the disease and the autopsy findings of seven deceased patients with verified COVID-19 were analyzed. The chest computed tomography (CT) scan was routinely performed while CT pulmonary angiography and a duplex ultrasound scan (DUS) of the lower limbs were used in cases of suspected VTE. The VTE prophylaxis was administered to all patients with intermediate or therapeutic doses of low-molecular-weight heparin. The histological examination of the lung tissue and other organs was performed with particular attention paid to the pulmonary vasculature.

Results

Venous thromboembolism, including deep vein thrombosis in one patient and pulmonary artery thrombosis in two patients, was confirmed by imaging tests despite anticoagulation. Systemic thrombolysis was performed in two patients with putative and confirmed pulmonary embolism. An autopsy revealed the signs of acute respiratory distress syndrome in all seven patients. Abnormalities of lung vessels were found in all cases and were represented by dystrophy and necrosis in the endothelium and muscle fibers, and by infiltration by plasmatic cells, neutrophils, and lymphocytes. Multiple clots of variable maturity were observed. All those changes developed despite anticoagulation and were preserved after systemic thrombolysis.

Conclusion

Inflammatory and prothrombotic changes in the arterial wall in parallel with the lack of lung perfusion may cause diffuse arterial thrombosis in the lungs. This background may be responsible for the low response to systemic anticoagulation and thrombolysis in severe forms of COVID-19.

The overlooked chamber in coronavirus disease 2019

Coronavirus disease 2019 (COVID-19) causes a pandemic around the globe. Debilitating and even deadly complications have occurred to the millions. A recent study reported 31% of right ventricular dilation in the hospitalized COVID-19 patients, which is significantly associated with the mortality. Therefore, we sought to search for the lines of evidence in the literature that COVID-19 may contribute to right heart dysfunction. The relevant literature and data from PubMed, Embase, Cochrane Library databases, and Web of Science were searched using the MeSH terms including 'COVID-19', 'SARS-CoV-2', 'novel coronavirus pneumonia', 'novel coronavirus', 'right heart failure', 'right heart dysfunction', 'pulmonary hypertension', 'pulmonary embolism', and various combinations. The collected literature and data were sorted and summarized. Literature reports that angiotensin-converting enzyme 2 (ACE2) is the host receptor mediating the cell entry of severe acute respiratory syndrome coronavirus 2. Clinical and experimental evidence shows that loss of function of ACE2 aggravates pulmonary hypertension and gain of function of ACE2 exerts protection on cardiopulmonary circulation. Moreover, the patients with COVID-19 are more susceptible to pulmonary embolism and severe pneumonia-induced acute respiratory distress syndrome. Therefore, COVID-19 may cause right heart dysfunction by inducing pulmonary hypertension, pulmonary embolism, and acute respiratory distress syndrome. Particular attention should be paid to the function of the right heart, the overlooked chamber in COVID-19. Blood gas analysis, laboratory test of cardiac injury markers, physical examination, and echocardiography should be performed to identify right heart failure as early as possible. Once the right heart failure is confirmed, the therapeutic modalities following the guidelines of European Society of Cardiology should be employed to reduce mortality.

Demystifying pulmonary vascular complications in severe coronavirus disease-19 pneumonia (COVID-19) in the light of clinico-radiologic-pathologic correlation

•Small pulmonary vessel changes are a unique imaging feature of COVID-19 pneumonia. •Autopsy studies reveal a very high incidence of peripheral pulmonary thrombosis. •Risk of thrombosis is high in severe COVID-19 despite anticoagulation. •Mounting evidence suggests immunothrombosis as a contributory cause of thrombosis. •Combined inflammation reduction and anticoagulation seems to be a rational therapeutic protocol.

Coagulopathy and Thrombosis as a Result of Severe COVID-19 Infection: A Microvascular Focus

Coronavirus disease of 2019 (COVID-19) is the clinical manifestation of the respiratory infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). While primarily recognized as a respiratory disease, it is clear that COVID-19 is systemic illness impacting multiple organ systems. One defining clinical feature of COVID-19 has been the high incidence of thrombotic events. The underlying processes and risk factors for the occurrence of thrombotic events in COVID-19 remain inadequately understood. While severe bacterial, viral, or fungal infections are well recognized to activate the coagulation system, COVID-19-associated coagulopathy is likely to have unique mechanistic features. Inflammatory-driven processes are likely primary drivers of coagulopathy in COVID-19, but the exact mechanisms linking inflammation to dysregulated hemostasis and thrombosis are yet to be delineated. Cumulative findings of microvascular thrombosis has raised question if the endothelium and microvasculature should be a point of investigative focus. von Willebrand factor (VWF) and its protease, a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS-13), play important role in the maintenance of microvascular hemostasis. In inflammatory conditions, imbalanced VWF-ADAMTS-13 characterized by elevated VWF levels and inhibited and/or reduced activity of ADAMTS-13 has been reported. Also, an imbalance between ADAMTS-13 activity and VWF antigen is associated with organ dysfunction and death in patients with systemic inflammation. A thorough understanding of VWF-ADAMTS-13 interactions during early and advanced phases of COVID-19 could help better define the pathophysiology, guide thromboprophylaxis and treatment, and improve clinical prognosis.

Hunting coronavirus by transmission electron microscopy - a guide to SARS-CoV-2-associated ultrastructural pathology in COVID-19 tissues

Transmission electron microscopy has become a valuable tool to investigate tissues of COVID‐19 patients because it allows visualisation of SARS‐CoV‐2, but the ‘virus‐like particles’ described in several organs have been highly contested. Because most electron microscopists in pathology are not accustomed to analysing viral particles and subcellular structures, our review aims to discuss the ultrastructural changes associated with SARS‐CoV‐2 infection and COVID‐19 with respect to pathology, virology and electron microscopy. Using micrographs from infected cell cultures and autopsy tissues, we show how coronavirus replication affects ultrastructure and put the morphological findings in the context of viral replication, which induces extensive remodelling of the intracellular membrane systems. Virions assemble by budding into the endoplasmic reticulum–Golgi intermediate complex and are characterised by electron‐dense dots of cross‐sections of the nucleocapsid inside the viral particles. Physiological mimickers such as multivesicular bodies or coated vesicles serve as perfect decoys. Compared to other in‐situ techniques, transmission electron microscopy is the only method to visualise assembled virions in tissues, and will be required to prove SARS‐CoV‐2 replication outside the respiratory tract. In practice, documenting in tissues the characteristic features seen in infected cell cultures seems to be much more difficult than anticipated. In our view, the hunt for coronavirus by transmission electron microscopy is still on.

In situ pulmonary thrombosis in patients with COVID-19 pneumonia: different phenotypes may exist

•In situ pulmonary thrombosis may exist in COVID-19 pneumonia patients with the feature of peripheral distribution. •Some thrombi located just within the consolidation lesions of the infected lungs, likely due to active local inflammation. •Some thrombi located in non-consolidation area, likely due to hypercoagulability caused by systemic inflammation. •We hypothesize different phenotypes of in situ thrombosis may exist and need different intensity of anticoagulant therapy.

COVID-19 and cardiovascular consequences: Is the endothelial dysfunction the hardest challenge?

A Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) has become a pandemic disease named Coronavirus Disease-19 (COVID-19) of epochal dimension. The clinical spectrum of COVID-19 is wide, ranging from asymptomatic forms to severe pneumonia, sepsis and multiple organ dysfunction syndromes resulting in poor outcomes. Among the various consequences of severe COVID-19, cardiovascular (CV) collapse appears the most serious and potentially lethal. On the other hand, pre-existent CV comorbidities are also associated with higher mortality. The most reliable hypothetical pathogenetic mechanism for CV complications and cardiac injury in severe COVID-19 patients appears to be a sustained endothelial dysfunction, caused by the interplay of inflammation and coagulation. In this review, we survey papers addressing issues related to severe COVID-19, characterized by enhanced lung microvascular loss, hypercytokinemia, hypoxemia and thrombosis. We discuss about how the virus-induced downregulation of the angiotensin converting enzyme-2 (ACE2) receptor, used to enter the host cell, could affect the renin-angiotensin system, attempting to clarify the doubts about the use of ACE inhibitors and Angiotensin-II receptor blockers in COVID-19 patients. Finally, we point out how the delicate and physiological homeostatic function of the endothelium, which turns into a disastrous battlefield of the complex interaction between "cytokine and coagulative storms", can be irreparably compromised and result in systemic inflammatory complications.

Coronavirus disease 2019 and the pancreas

Coronavirus disease 2019 (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has led to a world-wide pandemic since its onset in December of 2019. Although, a primary respiratory pathogen, over the ensuing period, its extra-pulmonary effects have come to the forefront. The virus, having multi-organ tropism, has been shown to affect a host of other organs beyond the lung, including the pancreas. The data on pancreatic involvement by COVID-19, however, have been limited. Moreover, whether the effects on the pancreas are due to the direct effects of the virus or is just an epi-phenomenon is debatable. The prevalence of pancreatic injury and degree of injury are the other issues that need to be addressed. Pancreatic cancer has a dismal prognosis and the management of the same in the COVID era needs to be tailored assessing the risk-benefit ratio for the same. Additionally, pancreatic surgery increases not only the morbidity of the patient, but also the risk of the operator and burden on the health care system. Hence, the decision for such major procedures needs to be rationalized for optimum benefit during this pandemic. Similarly, for the endoscopist, pancreatic endoscopy needs to be carefully regulated to reduce risk to both the patient and the physician and yet deliver optimum patient care. This review gives a concise summary of various aspects of pancreatic involvement and pancreatic disease management during this pandemic.

COVID-19 in the elderly people and advances in vaccination approaches

The rapid worldwide spread of the COVID-19 pandemic, caused by the newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in tens of millions of infections and over one million deaths. SARS-CoV-2 infection affects all age groups; however, those over 60 years old are affected more severely. Moreover, pre-existing co-morbidities result in higher COVID-19-associated mortality in the geriatric population. This article highlights the associated risk factors of SARS-CoV-2 infection in older people and progress in developing COVID-19 vaccines, especially for efficient vaccination of the older population. There is also a summary of immunomodulatory and immunotherapeutic approaches to ameliorate the outcome of COVID-19 in older individuals.

A Systematic Review of the Cardiovascular Manifestations and Outcomes in the Setting of Coronavirus-19 Disease

The impact of coronavirus disease, 2019 (COVID-19), has been profound. Though COVID-19 primarily affects the respiratory system, it has also been associated with a wide range of cardiovascular (CV) manifestations portending extremely poor prognosis. The principal hypothesis for CV involvement is through direct myocardial infection and systemic inflammation. We conducted a systematic review of the current literature to provide a foundation for understanding the CV manifestations and outcomes of COVID-19. PubMed and EMBASE databases were electronically searched from the inception of the databases through 27 April 2020. A second literature review was conducted to include major trials and guidelines that were published after the initial search but before submission. The inclusion criteria for studies to be eligible were case reports, case series, and observation studies reporting CV outcomes among patients with COVID-19 infection. This review of the current COVID-19 disease and CV outcomes literature revealed a myriad of CV manifestations with potential avenues for treatment and prevention. Future studies are required to understand on a more mechanistic level the effect of COVID-19 on the myocardium and thus provide avenues to improve mortality and morbidity.

Venous Thromboembolism in COVID-19

The coronavirus disease 2019 (COVID-19) is our latest pandemic, preceded by the H1N1 swine flu in 2009, which lasted approximately 19 months. One of the special characteristics of COVID-19 is the propensity to cause venous thromboembolism (VTE). Thromboinflammation seems to play a prominent role in the pathogenesis. We will here review some mechanisms in the pathogenesis and discuss some hematological biomarkers, and also whether they serve as useful risk factors for VTE. The role of general risk assessment models for medically ill patients specifically in COVID-19 is appraised. The type of prophylaxis and particularly whether standard or augmented doses of chemoprophylaxis should be used is reviewed based on available evidence. We are also comparing recommendations from 10 different guidance or position/consensus statements. Treatment recommendations for patients with COVID-19 and pulmonary embolism are discussed with current general treatment guidelines as reference. Specifics for patients with COVID-19 are pointed out and the potential role of thrombolytic treatment is explored.

Thromboembolism risk of COVID-19 is high and associated with a higher risk of mortality: A systematic review and meta-analysis

BACKGROUND

Studies have suggested that there is increased risk of thromboembolism (TE) associated with coronavirus disease 2019 (COVID-19). However, overall arterial and venous TE rates of COVID-19 and effect of TE on COVID-19 mortality is unknown.

METHODS

We did a systematic review and meta-analysis of studies evaluating TE in COVID-19. We searched PubMed, Cochrane, and Embase for studies published up to June 12, 2020. Random effects models were used to produce summary TE rates and odds ratios (OR) of mortality in COVID-19 patients with TE compared to those without TE. Heterogeneity was quantified with I 2 .

FINDINGS

Of 425 studies identified, 42 studies enrolling 8271 patients were included in the meta-analysis. Overall venous TE rate was 21% (95% CI:17-26%): ICU, 31% (95% CI: 23-39%). Overall deep vein thrombosis rate was 20% (95% CI: 13-28%): ICU, 28% (95% CI: 16-41%); postmortem, 35% (95% CI:15-57%). Overall pulmonary embolism rate was 13% (95% CI: 11-16%): ICU, 19% (95% CI:14-25%); postmortem, 22% (95% CI:16-28%). Overall arterial TE rate was 2% (95% CI: 1-4%): ICU, 5% (95%CI: 3-7%). Pooled mortality rate among patients with TE was 23% (95%CI:14-32%) and 13% (95% CI:6-22%) among patients without TE. The pooled odds of mortality were 74% higher among patients who developed TE compared to those who did not (OR, 1.74; 95%CI, 1.01-2.98; P = 0.04).

INTERPRETATION

TE rates of COVID-19 are high and associated with higher risk of death. Robust evidence from ongoing clinical trials is needed to determine the impact of thromboprophylaxis on TE and mortality risk of COVID-19.

FUNDING

None.

Depletion of circulating IgM memory B cells predicts unfavourable outcome in COVID-19

Impaired immune responses have been hypothesised to be a possible trigger of unfavourable outcomes in coronavirus disease 2019 (COVID-19). We aimed to characterise IgM memory B cells in patients with COVID-19 admitted to an internal medicine ward in Northern Italy. Overall, 66 COVID-19 patients (mean age 74 ± 16.6 years; 29 females) were enrolled. Three patients (4.5%; 1 female) had been splenectomised and were excluded from further analyses. Fifty-five patients (87.3%) had IgM memory B cell depletion, and 18 (28.6%) died during hospitalisation (cumulative incidence rate 9.26/100 person-week; 5.8-14.7 95% CI). All patients who died had IgM memory B cell depletion. A superimposed infection was found in 6 patients (9.5%), all of them having IgM memory B cell depletion (cumulative incidence rate 3.08/100 person-week; 1.3-6.8 95% CI). At bivariable analyses, older age, sex, number of comorbidities, and peripheral blood lymphocyte count < 1500/µl were not correlated with IgM memory B cell depletion. A discrete-to-marked reduction of the B-cell compartment was also noticed in autoptic spleen specimens of two COVID-19 patients. We conclude that IgM memory B cells are commonly depleted in COVID-19 patients and this correlates with increased mortality and superimposed infections.

COVID-19 Autopsies: A Case Series from Poland

This paper presents autopsy findings of 3 COVID-19 patients randomly selected for post-mortem from two tertiary referral Polish hospitals. Analysis of macroscopic, histopathological findings with clinical features was performed. All 3 deceased patients were Caucasian males (average age 61 years, range from 56 to 68 years). Using real-time polymerase chain reaction assay, the patients were confirmed (antemortem) to have severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Two patients were obese, and 1 patient had type 2 diabetes mellitus. The medical history of 1 patient included hemorrhagic pancreatitis, gangrenous cholecystitis, Acinetobacter baumanii sepsis, and cholecystectomy. Pulmonary embolism was diagnosed in 2 patients. At autopsy, in 1 case, the lungs showed bilateral interstitial pneumonia with diffuse alveolar damage (DAD), while in another case, interstitial pulmonary lymphoid infiltrates and enlarged atypical pneumocytes were present but without DAD. Microthrombi in lung vessels and capillaries were observed in 2 cases. This study revealed thrombotic complications of COVID-19 and interstitial pneumonia with DAD presence as the main autopsy findings in patients with SARS-CoV-2 infection that was confirmed antemortem with molecular tests. Autopsy studies using tissue sections handled in accordance with SARS-CoV-2 biosafety guidelines are urgently needed, especially in the case of subjects who were below the age of 60.

Fatality rate and predictors of mortality in an Italian cohort of hospitalized COVID-19 patients

Clinical features and natural history of coronavirus disease 2019 (COVID-19) differ widely among different countries and during different phases of the pandemia. Here, we aimed to evaluate the case fatality rate (CFR) and to identify predictors of mortality in a cohort of COVID-19 patients admitted to three hospitals of Northern Italy between March 1 and April 28, 2020. All these patients had a confirmed diagnosis of SARS-CoV-2 infection by molecular methods. During the study period 504/1697 patients died; thus, overall CFR was 29.7%. We looked for predictors of mortality in a subgroup of 486 patients (239 males, 59%; median age 71 years) for whom sufficient clinical data were available at data cut-off. Among the demographic and clinical variables considered, age, a diagnosis of cancer, obesity and current smoking independently predicted mortality. When laboratory data were added to the model in a further subgroup of patients, age, the diagnosis of cancer, and the baseline PaO₂/FiO₂ ratio were identified as independent predictors of mortality. In conclusion, the CFR of hospitalized patients in Northern Italy during the ascending phase of the COVID-19 pandemic approached 30%. The identification of mortality predictors might contribute to better stratification of individual patient risk.

Longitudinal Multi-omics Analyses Identify Responses of Megakaryocytes, Erythroid Cells, and Plasmablasts as Hallmarks of Severe COVID-19

Temporal resolution of cellular features associated with a severe COVID-19 disease trajectory is needed for understanding skewed immune responses and defining predictors of outcome. Here, we performed a longitudinal multi-omics study using a two-center cohort of 14 patients. We analyzed the bulk transcriptome, bulk DNA methylome, and single-cell transcriptome (>358,000 cells, including BCR profiles) of peripheral blood samples harvested from up to 5 time points. Validation was performed in two independent cohorts of COVID-19 patients. Severe COVID-19 was characterized by an increase of proliferating, metabolically hyperactive plasmablasts. Coinciding with critical illness, we also identified an expansion of interferon-activated circulating megakaryocytes and increased erythropoiesis with features of hypoxic signaling. Megakaryocyte- and erythroid-cell-derived co-expression modules were predictive of fatal disease outcome. The study demonstrates broad cellular effects of SARS-CoV-2 infection beyond adaptive immune cells and provides an entry point toward developing biomarkers and targeted treatments of patients with COVID-19.

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SARS-CoV2 infection elicits dynamic changes of circulating cells in the blood

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Severe COVID-19 is characterized by increased metabolically active plasmablasts

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Elevation of IFN-activated megakaryocytes and erythroid cells in severe COVID-19

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Cell-type-specific expression signatures are associated with a fatal COVID-19 outcome