Prominent changes in blood coagulation of patients with SARS-CoV-2 infection

Coagulopathy in COVID-19: Focus on vascular thrombotic events

SARS-CoV-2 causes a phenotype of pneumonia with diverse manifestation, which is termed as coronavirus disease 2019 (COVID-19). An impressive high transmission rate allows COVID-19 conferring enormous challenge for clinicians worldwide, and developing to a pandemic level. Combined with a series of complications, a part of COVID-19 patients progress into severe cases, which critically contributes to the risk of fatality. To date, coagulopathy has been found as a prominent feature of COVID-19 and severe coagulation dysfunction may be associated with poor prognosis. Coagulopathy in COVID-19 may predispose patients to hypercoagulability-related disorders including thrombosis and even fatal vascular events. Inflammatory storm, uncontrolled inflammation-mediated endothelial injury and renin angiotensin system (RAS) dysregulation are the potential mechanisms. Ongoing efforts made to develop promising therapies provide several potential strategies for hypercoagulability in COVID-19. In this review, we introduce the clinical features of coagulation and the increased vascular thrombotic risk conferred by coagulopathy according to present reports about COVID-19. The potential underlying mechanisms and emerging therapeutic avenues are discussed, emphasizing an urgent need for effective interventions.

Antiphospholipid antibodies in patients with COVID-19: A relevant observation?

BACKGROUND

High incidence of thrombosis in COVID-19 patients indicates a hypercoagulable state. Hence, exploring the involvement of antiphospholipid antibodies (aPL) in these patients is of interest.

OBJECTIVES

To illustrate the incidence of criteria (lupus anticoagulant [LAC], anticardiolipin [aCL] immunoglobulin G [IgG]/IgM, antibeta2-glycoprotein I antibodies [aβ2GPI] IgG/IgM) and noncriteria (anti-phosphatidyl serine/prothrombin [aPS/PT], aCL, and aβ2GPI IgA) aPL in a consecutive cohort of critically ill SARS-CoV-2 patients, their association with thrombosis, antibody profile and titers of aPL.

PATIENTS/METHODS

Thirty-one consecutive confirmed COVID-19 patients admitted to the intensive care unit were included. aPL were measured at one time point, with part of the aPL-positive patients retested after 1 month.

RESULTS

Sixteen patients were single LAC-positive, two triple-positive, one double-positive, one single aCL, and three aCL IgG and LAC positive. Seven of nine thrombotic patients had at least one aPL. Sixteen of 22 patients without thrombosis were aPL positive, amongst them two triple positives. Nine of 10 retested LAC-positive patients were negative on a second occasion, as well as the double-positive patient. Seven patients were aPS/PT-positive associated to LAC. Three patients were aCL and aβ2GPI IgA-positive.

CONCLUSION

Our observations support the frequent single LAC positivity during (acute phase) observed in COVID-19 infection; however, not clearly related to thrombotic complications. Triple aPL positivity and high aCL/aβ2GPI titers are rare. Repeat testing suggests aPL to be mostly transient. Further studies and international registration of aPL should improve understanding the role of aPL in thrombotic COVID-19 patients.

Thrombosis in Coronavirus disease 2019 (COVID-19) through the prism of Virchow's triad

The pathogenesis of Coronavirus disease 2019 (COVID-19) is gradually being comprehended. A high number of thrombotic episodes are reported, along with the mortality benefits of heparin. COVID-19 can be viewed as a prothrombotic disease. We overviewed the available evidence to explore this possibility. We identified various histopathology reports and clinical case series reporting thromboses in COVID-19. Also, multiple coagulation markers support this. COVID-19 can be regarded as a risk factor for thrombosis. Applying the principles of Virchow's triad, we described abnormalities in the vascular endothelium, altered blood flow, and platelet function abnormalities that lead to venous and arterial thromboses in COVID-19. Endothelial dysfunction, activation of the renin-angiotensin-aldosterone system (RAAS) with the release of procoagulant plasminogen activator inhibitor (PAI-1), and hyperimmune response with activated platelets seem to be significant contributors to thrombogenesis in COVID-19. Stratifying risk of COVID-19 thromboses should be based on age, presence of comorbidities, D-dimer, CT scoring, and various blood cell ratios. Isolated heparin therapy may not be sufficient to combat thrombosis in this disease. There is an urgent need to explore newer avenues like activated protein C, PAI-1 antagonists, and tissue plasminogen activators (tPA). These should be augmented with therapies targeting RAAS, antiplatelet drugs, repurposed antiinflammatory, and antirheumatic drugs. Key Points • Venous and arterial thromboses in COVID-19 can be viewed through the prism of Virchow's triad. • Endothelial dysfunction, platelet activation, hyperviscosity, and blood flow abnormalities due to hypoxia, immune reactions, and hypercoagulability lead to thrombogenesis in COVID-19. • There is an urgent need to stratify COVID-19 patients at risk for thrombosis using age, comorbidities, D-dimer, and CT scoring. • Patients with COVID-19 at high risk for thrombosis should be put on high dose heparin therapy.

Thrombin Inhibition by Argatroban: Potential Therapeutic Benefits in COVID-19

Thrombin is a trypsin-like serine protease with multiple physiological functions. Its role in coagulation and thrombosis is well-established. Nevertheless, thrombin also plays a major role in inflammation by activating protease-activated receptors. In addition, thrombin is also involved in angiogenesis, fibrosis, and viral infections. Considering the pathogenesis of COVID-19 pandemic, thrombin inhibitors may exert multiple potential therapeutic benefits including antithrombotic, anti-inflammatory, and antiviral activities. In this review, we describe the clinical features of COVID-19, the thrombin’s roles in various pathologies, and the potential of argatroban in COVID-19 patients. Argatroban is a synthetic, small molecule, direct, competitive, and selective inhibitor of thrombin. It is approved to parenterally prevent and/or treat heparin-induced thrombocytopenia in addition to other thrombotic conditions. Argatroban also possesses anti-inflammatory and antiviral activities and has a well-established pharmacokinetics profile. It also appears to lack a significant risk of drug–drug interactions with therapeutics currently being evaluated for COVID-19. Thus, argatroban presents a substantial promise in treating severe cases of COVID-19; however, this promise is yet to be established in randomized, controlled clinical trials.

Pathogenesis, clinical manifestations and complications of coronavirus disease 2019 (COVID-19)

Aim: Despite the similarities in the pathogenesis of the beta coronaviruses, the precise infective mechanisms of SARS-CoV-2 remain unclear. Objective: In this review, we aim to focus on the proposed theories behind the pathogenesis of SARS-CoV-2 and highlight the clinical complications related to COVID-19. Methods: We conducted a literature search in Pubmed, Scopus and Google Scholar for the relevant articles regarding clinical complications and pathogenesis of COVID-19. Results: Related articles were included and discussed. Conclusion: Respiratory system and the lungs are the most commonly involved sites of COVID-19 infection. Cardiovascular, liver, kidneys, gastrointestinal and central nervous systems are involved with different frequencies and degrees of severity.

Coagulopathy of Coronavirus Disease 2019

OBJECTIVES

Recent studies have reported a high prevalence of thrombotic events in coronavirus disease 2019. However, the significance of thromboembolic complications has not been widely appreciated. The purpose of this review is to provide current knowledge of this serious problem.

DESIGN

Narrative review.

DATA SOURCES

Online search of published medical literature through PubMed using the term "COVID-19," "SARS," "acute respiratory distress syndrome," "coronavirus," "coagulopathy," "thrombus," and "anticoagulants."

STUDY SELECTION AND DATA EXTRACTION

Articles were chosen for inclusion based on their relevance to coagulopathy and thrombosis in coronavirus disease 2019, and anticoagulant therapy. Reference lists were reviewed to identify additional relevant articles.

DATA SYNTHESIS

Coronavirus disease 2019 is associated with a strikingly high prevalence of coagulopathy and venous thromboembolism that may contribute to respiratory deterioration. Monitoring coagulation variables is important, as abnormal coagulation tests are related to adverse outcomes and may necessitate adjuvant antithrombotic interventions. In the initial phase of the infection, D-dimer and fibrinogen levels are increased, while activated partial prothrombin time, prothrombin time, and platelet counts are often relatively normal. Increased D-dimer levels three times the upper limit of normal may trigger screening for venous thromboembolism. In all hospitalized patients, thromboprophylaxis using low-molecular-weight heparin is currently recommended. The etiology of the procoagulant responses is complex and thought to be a result of specific interactions between host defense mechanisms and the coagulation system. Although the coagulopathy is reminiscent of disseminated intravascular coagulation and thrombotic microangiopathy, it has features that are markedly distinct from these entities.

CONCLUSIONS

Severe acute respiratory syndrome coronavirus 2/coronavirus disease 2019 frequently induces hypercoagulability with both microangiopathy and local thrombus formation, and a systemic coagulation defect that leads to large vessel thrombosis and major thromboembolic complications, including pulmonary embolism in critically ill hospitalized patients. D-dimers and fibrinogen levels should be monitored, and all hospitalized patients should undergo thromboembolism prophylaxis with an increase in therapeutic anticoagulation in certain clinical situations.

A meta-analysis of potential biomarkers associated with severity of coronavirus disease 2019 (COVID-19)

BACKGROUND

Prognostic factors for the Coronavirus disease 2019 (COVID1-9) are not well established. This study aimed to summarize the available data on the association between the severity of COVID-19 and common hematological, inflammatory and biochemical parameters.

METHODS

EMBASE, MEDLINE, Web of sciences were searched to identify all published studies providing relevant data. Random-effects meta-analysis was used to pool effect sizes.

RESULTS

The bibliographic search yielded 287 citations, 31 of which were finally retained. Meta-analysis of standardized mean difference (SMD) between severe and non-severe COVID-19 cases showed that CK-MB (SMD = 0.68,95%CI: 0.48;0.87; P-value:< 0.001), troponin I (SMD = 0.71, 95%CI:0.42;1.00; P-value:< 0.001), D-dimer (SMD = 0.54,95%CI:0.31;0.77; P-value:< 0.001), prothrombin time (SMD = 0.48, 95%CI:0.23;0.73; P-value: < 0.001), procalcitonin (SMD = 0.72, 95%CI: 0.34;1,11; P-value:< 0.001), interleukin-6 (SMD = 0.93, 95%CI: 0.25;1.61;P-value: 0.007),C-reactive protein (CRP) (SMD = 1.34, 95%CI:0.83;1.86; P-value:< 0.001), ALAT (SMD = 0.53, 95%CI: 0.34;0,71; P-value:< 0.001), ASAT (SMD = 0.96, 95%CI: 0.58;1.34; P-value: < 0.001), LDH (SMD = 1.36, 95%CI: 0.75;1.98; P-value:< 0.001), CK (SMD = 0.48, 95%CI: 0.10;0.87; P-value:0.01), total bilirubin (SMD = 0.32, 95%CI: 0.18;0.47;P-value: < 0.001), γ-GT (SMD = 1.03, 95%CI: 0.83;1.22; P-value: < 0.001), myoglobin (SMD = 1.14, 95%CI: 0.81;1.47; P-value:< 0.001), blood urea nitrogen (SMD = 0.32, 95%CI: 0.18;0.47;P-value:< 0.001) and Creatininemia (SMD = 0.18, 95%CI: 0.01;0.35; P-value:0.04) were significantly more elevated in severe cases, in opposition to lymphocyte count (SMD = -0.57, 95%CI:-0.71; - 0.42; P-value: < 0.001) and proportion of lymphocytes (SMD = -0.81, 95%CI: - 1.12; - 0.49; P-value:< 0.001) which were found to be significantly lower in severe patients with other biomarker such as thrombocytes (SMD = -0.26, 95%CI: - 0.48; - 0.04; P-value:0.02), eosinophils (SMD = - 0.28, 95%CI:-0.50; - 0.06; P-value:0.01), haemoglobin (SMD = -0.20, 95%CI: - 0.37,-0.03; P-value:0.02), albuminemia (SMD-1.67,95%CI -2.40; - 0.94; P-value:< 0.001), which were also lower. Furthermore, severe COVID-19 cases had a higher risk to have lymphopenia (RR =1.66, 95%CI: 1.26;2.20; P-value:0.002), thrombocytopenia (RR = 1.86, 95%CI: 1.59;2.17; P-value: < 0.001), elevated procalcitonin level (RR = 2.94, 95%CI: 2.09-4.15; P-value:< 0.001), CRP (RR =1.41,95%CI: 1.17-1.70; P-value:0.003), ASAT(RR =2.27, 95%CI: 1.76;2.94; P-value:< 0.001), CK(RR = 2.61, 95%CI: 1.35;5.05; P-value: 0.01), Creatininemia (RR = 3.66, 95%CI: 1.53;8.81; P-value: 0.02) and LDH blood level (RR = 2.03, 95%CI: 1.42;290; P-value: 0.003).

CONCLUSION

Some inflammatory (procalcitonin, CRP), haematologic (lymphocyte, Thrombocytes), and biochemical (CK-MB, Troponin I, D-dimer, ASAT, ALAT, LDH, γ-GT) biomarkers are significantly associated with severe COVID-19. These biomarkers might help in prognostic risk stratification of patients with COVID-19.

Early coagulation tests predict risk stratification and prognosis of COVID-19

The ongoing outbreak of Coronavirus Disease 2019 (COVID-19) is hitting the world hard, but the relationship between coagulation disorders and COVID-19 is still not clear. This study aimed to explore whether early coagulation tests can predict risk stratification and prognosis. PubMed, Web of Science, Cochrane Library, and Scopus were searched electronically for relevant research studies published up to March 24, 2020, producing 24 articles for the final inclusion. The pooled standard mean difference (SMD) of coagulation parameters at admission were calculated to determine severe and composite endpoint conditions (ICU or death) in COVID-19 patients. Meta-analyses revealed that platelet count was not statistically related to disease severity and composite endpoint; elevated D-dimer correlated positively with disease severity (SMD 0.787 (0.277-1.298), P= 0.003, I²= 96.7%) but had no significant statistical relationship with composite endpoints. Similarly, patients with prolonged prothrombin time (PT) had an increased risk of ICU and increased risk of death (SMD 1.338 (0.551-2.125), P = 0.001, I² = 92.7%). Besides, increased fibrin degradation products (FDP) and decreased antithrombin might also mean the disease is worsening. Therefore, early coagulation tests followed by dynamic monitoring is useful for recognizing coagulation disorders accompanied by COVID-19 and guiding timely therapy to improve prognosis.

A Peculiar Case of Small Bowel Stricture in a Coronavirus Disease 2019 Patient with Congenital Adhesion Band and Superior Mesenteric Vein Thrombosis

Background

There is increasing evidence supporting coronavirus disease 2019 (COVID-19)-related coagulopathy. In the available literature, only 2 cases of superior mesenteric vein thrombosis have been described.

Methods

We present a peculiar case of high-grade small bowel obstruction in a patient with COVID-19 infection.

Results

Exploratory laparotomy revealed a congenital adhesion band with associated focal bowel ischemia contributed by superior mesenteric vein thrombosis and positive lupus anticoagulant.

Conclusions

It is important to consider the rare differential of mesenteric vein thrombosis and its related sequelae of mesenteric ischemia in a patient with COVID-19 who presents with abdominal pain.

Crucial laboratory parameters in COVID-19 diagnosis and prognosis: An updated meta-analysis

INTRODUCTION AND OBJECTIVES

Common laboratory parameters are crucial in aiding coronavirus disease 2019 (COVID-19) case detection. This study aimed to determine the differences between laboratory parameters in (1) COVID-19 versus non-COVID-19 pneumonia, and (2) severe versus non-severe COVID-19 cases.

METHODS

Studies were collected until March 2020, and retrieved parameters include leukocyte, neutrophil, thrombocyte, and lymphocyte counts in addition to C-reactive protein (CRP), procalcitonin (PCT) and D-dimer levels. In the presence of heterogeneity, the random-effect model (REM) was used instead of the fixed-effect model (FEM).

RESULTS

Seven studies in the first analysis showed significantly lower leukocyte, neutrophil and platelet counts in COVID-19 pneumonia (SMD=-0.42, 95%CI -0.60 to -0.25, p<0.00001, SMD=-0.23, 95%CI -0.41 to -0.06, p=0.01, SMD=-0.54, 95%CI -0.91 to -0.16, p=0.0005) compared to non-COVID-19 pneumonia. Twenty-six studies in the second analysis showed significantly lower lymphocyte and thrombocyte counts (SMD=-0.56, 95%CI -0.71 to -0.40, p<0.0001, SMD=-0.32, 95%CI -0.49 to -0.15, p=0.0002) and significantly higher leukocyte, neutrophil, D-dimer, and CRP (SMD=0.31, 95%CI 0.07-0.56, p=0.01; SMD=0.44, 95%CI 0.24-0.64, p<0.0001; SMD=0.53, 95%CI 0.31-0.75, p<0.00001; SMD=0.97, 95%CI 0.70-1.24, p<0.00001) in severe COVID-19 compared to non-severe COVID-19.

CONCLUSIONS

In conclusion, thrombocyte count is key in both diagnosis and prognosis. Low leukocyte and neutrophil counts are markers of COVID-19 infection, but contrastingly higher counts indicate progressive COVID-19. And although lymphocyte, D-dimer and CRP levels did not demonstrate diagnostic value, all indicate severity of COVID-19. Confirmation of these findings should be performed in future studies.

Awareness and Prophylaxis of Venous Thromboembolism in Patients with COVID-19: A National Cross-Sectional Survey in Epidemic Era

Aim: Patients with acute infectious diseases are at an increased risk of venous thromboembolism (VTE). Clinicians should be aware of the VTE risk in patients with COVID-19, many of whom present with severe coagulation disorders.

Method: We used an online platform to conduct a cross-sectional questionnaire survey among doctors in mainland China in March 2020. The questionnaire was designed to figure out the clinician's current awareness of VTE prevention and detection rates, as well as the current status of VTE prophylaxis in patients with COVID-19.

Results: We collected 1,636 replies, of which 1,579 were valid. Among these, 991 (63%) clinicians were involved directly in frontline treatment. Most of the clinicians (1,492, or 94%) thought it was necessary to assess the VTE risk in patients with COVID-19. However, only 234 (24%) clinicians performed appropriate assessment during the COVID-19 outbreak. For patients with mild/moderate COVID-19, 752 (76%) clinicians would prescribe exercise and water to prevent VTE. For patients with severe COVID-19, 448 (45%) clinicians would prescribe mechanical devices if the patient had a high bleeding risk, and 648 (65%) clinicians would choose LMWH as prophylaxis if the patient had a low bleeding risk. The VTE detection rate was not that high in both mild/moderate and severe patients.

Conclusion: Although most clinicians recommended prescribing VTE prophylaxis to patients with COVID-19, the practice still needs to be improved. A real-world registry to investigate the true incidence of VTE, and the effect of prescribing appropriate prophylaxis for patients with COVID-19, is necessary in the future.

Crucial laboratory parameters in COVID-19 diagnosis and prognosis: An updated meta-analysis

INTRODUCTION AND OBJECTIVES

Common laboratory parameters are crucial in aiding coronavirus disease 2019 (COVID-19) case detection. This study aimed to determine the differences between laboratory parameters in (1) COVID-19 versus non-COVID-19 pneumonia, and (2) severe versus non-severe COVID-19 cases.

METHODS

Studies were collected until March 2020, and retrieved parameters include leukocyte, neutrophil, thrombocyte, and lymphocyte counts in addition to C-reactive protein (CRP), procalcitonin (PCT) and D-dimer levels. In the presence of heterogeneity, the random-effect model (REM) was used instead of the fixed-effect model (FEM).

RESULTS

Seven studies in the first analysis showed significantly lower leukocyte, neutrophil and platelet counts in COVID-19 pneumonia (SMD = -0.42, 95%CI -0.60 to -0.25, p < 0.00001, SMD = -0.23, 95%CI -0.41 to -0.06, p = 0.01, SMD = -0.54, 95%CI -0.91 to -0.16, p = 0.0005) compared to non-COVID-19 pneumonia. Twenty-six studies in the second analysis showed significantly lower lymphocyte and thrombocyte counts (SMD = -0.56, 95%CI -0.71 to -0.40, p < 0.0001, SMD = -0.32, 95%CI -0.49 to -0.15, p = 0.0002) and significantly higher leukocyte, neutrophil, D-dimer, and CRP (SMD = 0.31, 95%CI 0.07-0.56, p = 0.01; SMD = 0.44, 95%CI 0.24-0.64, p < 0.0001; SMD = 0.53, 95%CI 0.31-0.75, p < 0.00001; SMD = 0.97, 95%CI 0.70-1.24, p < 0.00001) in severe COVID-19 compared to non-severe COVID-19.

CONCLUSIONS

In conclusion, thrombocyte count is key in both diagnosis and prognosis. Low leukocyte and neutrophil counts are markers of COVID-19 infection, but contrastingly higher counts indicate progressive COVID-19. And although lymphocyte, D-dimer and CRP levels did not demonstrate diagnostic value, all indicate severity of COVID-19. Confirmation of these findings should be performed in future studies.

Cardiovascular System in COVID-19: Simply a Viewer or a Leading Actor?

As of January 2020, a new pandemic has spread from Wuhan and caused thousands of deaths worldwide. Several studies have observed a relationship between coronavirus disease (COVID-19) infection and the cardiovascular system with the appearance of myocardial damage, myocarditis, pericarditis, heart failure and various arrhythmic manifestations, as well as an increase in thromboembolic risk. Cardiovascular manifestations have been highlighted especially in older and more fragile patients and in those with multiple cardiovascular risk factors such as cancer, diabetes, obesity and hypertension. In this review, we will examine the cardiac involvement associated with SARS-CoV-2 infection, focusing on the pathophysiological mechanism underlying manifestations and their clinical implication, taking into account the main scientific papers published to date.

The Role of Therapeutic Anticoagulation in COVID-19

Coagulopathy has proven to be a common complication of the novel coronavirus SARS-CoV-2, with evidence of elevated D-dimers and fibrin degradation products associated with an increased incidence of thromboembolism. Despite emerging evidence describing the coagulopathy and its clinical relevance in COVID-19, fewer studies have addressed the potential role of empiric therapeutic anticoagulation in this setting. We report the case of a patient admitted to our intensive care unit (ICU) with severe acute respiratory distress syndrome (ARDS) secondary to COVID-19 whose clinical trajectory improved dramatically after initiation of a therapeutic dose of LMWH. The patient showed progressive elevation of fibrinogen and D-dimers despite a prophylactic dose of LMWH during her ICU stay. This was met with a moderate increase of troponin T-hs, an escalating need for vasopressors, and a progressive decrease in her P/F ratio despite preserved lung static compliance. Her platelet count was normal and had an elevated fibrinogen during the first week of ICU stay. The ECG was normal, and a bedside transthoracic echocardiogram showed no evidence of pulmonary embolism and a preserved EF with no regional wall motion abnormalities (RMWA). The chest X-ray was not dissimilar to previous exams, and the ABG showed hypoxia with normal pCO2 values. The decision was made to commence empiric therapeutic enoxaparin. The patient did not experience bleeding complications, and her clinical trajectory appeared to change dramatically. She was successfully extubated three days later and proceeded to clinical recovery and eventual discharge from the ICU. The available evidence shows that there is undoubtedly coagulopathy associated with COVID-19 with various subsequent forms of clinical manifestation described in the literature. Evidence also shows the benefits of heparin as an anticoagulant. From the discussion of this case report, however, it can be concluded that despite the plausible theoretical rationale, studies pertaining to the role of empiric therapeutic anticoagulation in this setting fall short of providing compelling evidence. Subsequently the role of empiric therapeutic anticoagulation in COVID-19 remains unclear with a pressing call for further research.

Research Progress of Genetic Structure, Pathogenic Mechanism, Clinical Characteristics, and Potential Treatments of Coronavirus Disease 2019

Coronavirus disease 2019 (COVID-19) is a global pandemic infectious disease caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), and currently affects more than 8 million people worldwide. SARS-CoV-2 mainly invades the cells by binding to the angiotensin converting enzyme 2 (ACE2) receptor, leading to the injury of respiratory system, cardiovascular system, digestive system, and urinary system, and even secondary to acute respiratory distress syndrome (ARDS) and systemic inflammatory response, resulting in multiple organ failure. In this review, mainly focusing on biogenesis and pathogenic mechanisms, we describe the recent progress in our understanding of SARS-CoV-2 and then summarize and discuss its crucial clinical characteristics and potential mechanism in different systems. Additionally, we discuss the potential treatments for COVID-19, aiming at a better understanding of the pathogenesis of SARS-CoV-2 and providing new ideas for the personalized treatment of COVID-19.

Extracellular Vesicle-Related Thrombosis in Viral Infection

Although the outcomes of viral infectious diseases are remarkably varied, most infections cause acute diseases after a short period. Novel coronavirus disease 2019, which recently spread worldwide, is no exception. Extracellular vesicles (EVs) are small circulating membrane-enclosed entities shed from the cell surface in response to cell activation or apoptosis. EVs transport various kinds of bioactive molecules between cells, including functional RNAs, such as viral RNAs and proteins. Therefore, when EVs are at high levels, changes in cell activation, inflammation, angioplasty and transportation suggest that EVs are associated with various diseases. Clinical research on EVs includes studies on the coagulatory system. In particular, abnormal enhancement of the coagulatory system through EVs can cause thrombosis. In this review, we address the functions of EVs, thrombosis, and their involvement in viral infection.

Prevalence of pulmonary embolism in patients with COVID-19 pneumonia and high D-dimer values: A prospective study

INTRODUCTION

Coronavirus disease 2019 (COVID-19) pneumonia is associated to systemic hyper-inflammation and abnormal coagulation profile. D-dimer elevation is particularly frequent, and values higher than 1μg/mL have been associated with disease severity and in-hospital mortality. Previous retrospective studies found a high pulmonary embolism (PE) prevalence, however, it should be highlighted that diagnoses were only completed when PE was clinically suspected.

MATERIAL AND METHODS

Single-center prospective cohort study. Between April 6th and April 17th 2020, consecutive confirmed cases of COVID-19 pneumonia with D-dimer >1 μg/mL underwent computed tomography pulmonary angiography (CTPA) to investigate the presence and magnitude of PE. Demographic and laboratory data, comorbidities, CTPA scores, administered treatments, and, clinical outcomes were analysed and compared between patients with and without PE.

RESULTS

Thirty consecutive patients (11 women) were included. PE was diagnosed in 15 patients (50%). In patients with PE, emboli were located mainly in segmental arteries (86%) and bilaterally (60%). Patients with PE were significantly older (median age 67.0 (IQR 63.0-73.0) vs. 57.0 (IQR 48.0-69.0) years, p = .048) and did not differ in sex or risk factors for thromboembolic disease from the non-PE group. D-dimer, platelet count, and, C reactive protein values were significantly higher among PE patients. D-dimer values correlated with the radiologic magnitude of PE (p<0.001).

CONCLUSIONS

Patients with COVID-19 pneumonia and D-dimer values higher than 1 μg/mL presented a high prevalence of PE, regardless of clinical suspicion. We consider that these findings could contribute to improve the prognosis of patients with COVID-19 pneumonia, by initiating anticoagulant therapy when a PE is found.

Hemostatic abnormalities in COVID-19: A guided review

The spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has already taken on pandemic proportions, affecting over 213 countries in a matter of weeks. In this context, several studies correlating hemostatic disorders with the infection dynamics of the new coronavirus have emerged. These studies have shown that a portion of the patients affected by Coronavirus Disease 2019 (COVID-19) have prolonged prothrombin time (PT) and activated partial thromboplastin time (APTT), elevated D-dimer levels and other fibrinolytic products, antithrombin (AT) activity reduced and decrease of platelet count. Based on these hallmarks, this review proposes to present possible pathophysiological mechanisms involved in the hemostatic changes observed in the pathological progression of COVID-19. In this analysis, it is pointed the relationship between the downregulation of angiotensin-converting enzyme 2 (ACE2) and storm cytokines action with the onset of hypercoagulability state, other than the clinical events involved in thrombocytopenia and hyperfibrinolysis progression.

Coagulation dysfunction in COVID-19: The interplay between inflammation, viral infection and the coagulation system

COVID-19 is a new pandemic, caused by Severe Acute Respiratory Syndrome-CoronaVirus-2 (SARS-Cov2) infection and characterized by a broad spectrum of clinical manifestations.

Inflammation and the innate immune system have been recently recognized as pivotal players in the most severe forms, characterized by significantly elevated levels of pro-inflammatory cytokines. In this setting, several studies have also reported the presence of abnormalities in coagulation parameters and platelets count, possibly identifying a subgroup of patients with poor prognosis. Some reports of full-blown thromboembolic events are emerging.

Among the possible mechanisms underlying coagulation dysfunction, the so-called "cytokine storm" seems to play a pivotal role. Other candidate factors include virus-specific mechanisms, related to the virus interaction with renin angiotensin system (RAS) and the fibrinolytic pathway, but also comorbidities affecting these patients.

Coagulation dysfunction is therefore a candidate risk factor for adverse outcomes in COVID-19 and should be carefully addressed in clinical practice.

The Anatomy of the SARS-CoV-2 Biomedical Literature: Introducing the CovidX Network Algorithm for Drug Repurposing Recommendation

BACKGROUND

Driven by the COVID-19 pandemic and the dire need to discover an antiviral drug, we explored the landscape of the SARS-CoV-2 biomedical publications to identify potential treatments.

OBJECTIVE

The aims of this study are to identify off-label drugs that may have benefits for the coronavirus disease pandemic, present a novel ranking algorithm called CovidX to recommend existing drugs for potential repurposing, and validate the literature-based outcome with drug knowledge available in clinical trials.

METHODS

To achieve such objectives, we applied natural language processing techniques to identify drugs and linked entities (eg, disease, gene, protein, chemical compounds). When such entities are linked, they form a map that can be further explored using network science tools. The CovidX algorithm was based upon a notion that we called "diversity." A diversity score for a given drug was calculated by measuring how "diverse" a drug is calculated using various biological entities (regardless of the cardinality of actual instances in each category). The algorithm validates the ranking and awards those drugs that are currently being investigated in open clinical trials. The rationale behind the open clinical trial is to provide a validating mechanism of the PubMed results. This ensures providing up to date evidence of the fast development of this disease.

RESULTS

From the analyzed biomedical literature, the algorithm identified 30 possible drug candidates for repurposing, ranked them accordingly, and validated the ranking outcomes against evidence from clinical trials. The top 10 candidates according to our algorithm are hydroxychloroquine, azithromycin, chloroquine, ritonavir, losartan, remdesivir, favipiravir, methylprednisolone, rapamycin, and tilorone dihydrochloride.

CONCLUSIONS

The ranking shows both consistency and promise in identifying drugs that can be repurposed. We believe, however, the full treatment to be a multifaceted, adjuvant approach where multiple drugs may need to be taken at the same time.

COVID-19: a probable role of the anticoagulant Protein S in managing COVID-19-associated coagulopathy

The COVID-19 pandemic has caused monumental mortality, and there are still no adequate therapies. Most severely ill COVID-19 patients manifest a hyperactivated immune response, instigated by interleukin 6 (IL6) that triggers a so called "cytokine storm" and coagulopathy. Hypoxia is also associated with COVID-19. So far overlooked is the fact that both IL6 and hypoxia depress the abundance of a key anticoagulant, Protein S. We speculate that the IL6-driven cytokine explosion plus hypoxemia causes a severe drop in Protein S level that exacerbates the thrombotic risk in COVID-19 patients. Here we highlight a mechanism by which the IL6-hypoxia curse causes a deadly hypercoagulable state in COVID-19 patients, and we suggest a path to therapy.

Highly sensitive quantification of plasma SARS-CoV-2 RNA shelds light on its potential clinical value

Background

Coronavirus disease 2019 (COVID-19) is a global public health problem that has already caused more than 662,000 deaths worldwide. Although the clinical manifestations of COVID-19 are dominated by respiratory symptoms, some patients present other severe damage such as cardiovascular, renal and liver injury or/and multiple organ failure, suggesting a spread of the SARS-CoV-2 in blood. Recent ultrasensitive polymerase chain reaction (PCR) technology now allows absolute quantification of nucleic acids in plasma. We herein intended to use the droplet-based digital PCR technology to obtain sensitive detection and precise quantification of plasma SARS-CoV-2 viral load (SARS-CoV-2 RNAaemia) in hospitalized COVID-19 patients.

Methods

Fifty-eight consecutive COVID-19 patients with pneumonia 8 to 12 days after onset of symptoms and 12 healthy controls were analyzed. Disease severity was categorized as mild-to-moderate in 17 patients, severe in 16 patients and critical in 26 patients. Plasma SARS-CoV-2 RNAaemia was quantified by droplet digital Crystal Digital PCR™ next-generation technology (Stilla Technologies, Villejuif, France).

Results

Overall, SARS-CoV-2 RNAaemia was detected in 43 (74.1%) patients. Prevalence of positive SARS-CoV-2 RNAaemia correlated with disease severity, ranging from 53% in mild-to-moderate patients to 88% in critically ill patients (p=0.036). Levels of SARS-CoV-2 RNAaemia were associated with severity (p=0.035). Among nine patients who experienced clinical deterioration during follow-up, eight had positive SARS-CoV-2 RNAaemia at baseline while only one critical patient with undetectable SARS-CoV-2 RNAaemia at the time of analysis died at day 27.

Conclusion

SARS-CoV-2 RNAaemia measured by droplet-based digital PCR constitutes a promising prognosis biomarker in COVID-19 patients

Are urologists in trouble with SARS-CoV-2? Reflections and recommendations for specific interventions

Objective

To assess the risk of viral infection during urological surgeries due to the possible hazards in tissue, blood, urine and aerosolised particles generated during surgery, and thus to understand the risks and make recommendations for clinical practice.

Patients and Methods

We reviewed the available literature on urological and other surgical procedures in patients with virus infections, such as human papillomavirus, human immunodeficiency virus and hepatitis B, and current publications on coronavirus disease 2019 (COVID‐19).

Results

Several possible pathways for viral transmission appear in the literature. Recently, groups have detected severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) in the urine and faeces, even after negative pharyngeal swabs. In addition, viral RNA can be detected in the blood and several tissues. During surgery, viral particles are released, aerosol‐borne and present a certain risk of transmission and infection. However, there is currently no evidence on the exact risk of infection from the agents mentioned above. It remains unclear whether or not viral particles in the urine, blood or faeces are infectious.

Conclusions

Whether SARS‐CoV‐2 can be transmitted by aerosols remains controversial. Irrespective of this, standard surgical masks offer inadequate protection from SARS‐CoV‐2. Full personal protective equipment, including at least filtering facepiece‐2 masks and safety goggles should be used. Aerosolised particles might remain for a long time in the operating theatre and contaminate other surfaces, e.g. floors or computer input devices. Therefore, scrupulous hygiene and disinfection of surfaces must be carried out. To prevent aerosolisation during laparoscopic interventions, the pneumoperitoneum should be evacuated with suction devices. The use of virus‐proof high‐efficiency particulate air filters is recommended. Local separation of anaesthesia/intubation and the operating theatre can reduce the danger of viral transmission. Lumbar anaesthesia should be considered especially in endourology. Based on current knowledge, COVID‐19 is not a contraindication for acute urological surgery. However, if possible, as European guideline committees recommend, non‐emergency urological interventions should be postponed until negative SARS‐CoV‐2 tests become available.

COVID-19-Associated Coagulopathy: An Exacerbated Immunothrombosis Response

Since the onset of the global pandemic in early 2020, coronavirus disease 2019 (COVID-19) has posed a multitude of challenges to health care systems worldwide. In order to combat these challenges and devise appropriate therapeutic strategies, it becomes of paramount importance to elucidate the pathophysiology of this illness. Coronavirus disease 2019, caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV2), is characterized by a dysregulated immune system and hypercoagulability. COVID-associated coagulopathy (CAC) was recognized based on profound d-dimer elevations and evidence of microthrombi and macrothrombi, both in venous and arterial systems. The underlying mechanisms associated with CAC have been suggested, but not clearly defined. The model of immunothrombosis illustrates the elaborate crosstalk between the innate immune system and coagulation. The rendering of a procoagulant state in COVID-19 involves the interplay of many innate immune pathways. The SARS-CoV2 virus can directly infect immune and endothelial cells, leading to endothelial injury and dysregulation of the immune system. Activated leukocytes potentiate a procoagulant state via release of intravascular tissue factor, platelet activation, NETosis, and inhibition of anticoagulant mechanisms. Additional pathways of specific relevance in CAC include cytokine release and complement activation. All these mechanisms have recently been reported in COVID-19. Immunothrombosis provides a comprehensive perspective of the several synergistic pathways pertinent to the pathogenesis of CAC.

ACE2 expression in adipose tissue is associated with COVID-19 cardio-metabolic risk factors and cell type composition

COVID-19 severity has varied widely, with demographic and cardio-metabolic factors increasing risk of severe reactions to SARS-CoV-2 infection, but the underlying mechanisms for this remain uncertain. We investigated phenotypic and genetic factors associated with subcutaneous adipose tissue expression of Angiotensin I Converting Enzyme 2 ( ACE2 ), which has been shown to act as a receptor for SARS-CoV-2 cellular entry. In a meta-analysis of three independent studies including up to 1,471 participants, lower adipose tissue ACE2 expression was associated with adverse cardio-metabolic health indices including type 2 diabetes (T2D) and obesity status, higher serum fasting insulin and BMI, and lower serum HDL levels (P<5.32x10 -4 ). ACE2 expression levels were also associated with estimated proportions of cell types in adipose tissue; lower ACE2 expression was associated with a lower proportion of microvascular endothelial cells (P=4.25x10 -4 ) and higher macrophage proportion (P=2.74x10 -5 ), suggesting a link to inflammation. Despite an estimated heritability of 32%, we did not identify any proximal or distal genetic variants (eQTLs) associated with adipose tissue ACE2 expression. Our results demonstrate that at-risk individuals have lower background ACE2 levels in this highly relevant tissue. Further studies will be required to establish how this may contribute to increased COVID-19 severity.

Association of Coronavirus Disease 2019 and Stroke: A Rising Concern

The severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) causes the coronavirus disease 2019 (COVID-19). It quickly became pandemic, and so did a new concern about COVID-19 infections increasing the risk for cerebrovascular diseases. There is an association between COVID-19 illness in people and acute stroke. Several chemical, mechanical, and/or inflammatory central nervous system pathologies are proposed to explain how this viral infection might induce acute cerebrovascular disease. Timely available evaluation and/or intervention is imperative for patients with concerns about acute cerebrovascular issues.

Neurological Manifestations of Severe SARS-CoV-2 Infection: Potential Mechanisms and Implications of Individualized Mechanical Ventilation Settings

In December 2019, an outbreak of illness caused by a novel coronavirus (2019-nCoV, subsequently renamed SARS-CoV-2) was reported in Wuhan, China. Coronavirus disease 2019 (COVID-19) quickly spread worldwide to become a pandemic. Typical manifestations of COVID-19 include fever, dry cough, fatigue, and respiratory distress. In addition, both the central and peripheral nervous system can be affected by SARS-CoV-2 infection. These neurological changes may be caused by viral neurotropism, by a hyperinflammatory and hypercoagulative state, or even by mechanical ventilation-associated impairment. Hypoxia, endothelial cell damage, and the different impacts of different ventilatory strategies may all lead to increased stress and strain, potentially exacerbating the inflammatory response and leading to a complex interaction between the lungs and the brain. To date, no studies have taken into consideration the possible secondary effect of mechanical ventilation on brain recovery and outcomes. The aim of our review is to provide an updated overview of the potential pathogenic mechanisms of neurological manifestations in COVID-19, discuss the physiological issues related to brain-lung interactions, and propose strategies for optimization of respiratory support in critically ill patients with SARS-CoV-2 pneumonia.

Host-directed therapies: a potential solution to combat COVID-19

Coronavirus disease 2019 (COVID-19) characterized by immuno-pathological host responses including pneumonia, lymphopenia, and cytokine storm that leads to severe lung inflammation, developed in acute respiratory distress syndrome (ARDS). In the absence of an effective vaccine or any definitive cure, the use of host-directed therapies is an effective alternative and demanding treatment option in the current pandemic outbreak of COVID-19.

Hemostatic Abnormalities in COVID-19: An Update

COVID-19 has emerged as a pandemic with lung being the primarily afflicted organ. Deranged hemostasis has been observed in patients with COVID-19 with scales tipped towards a prothrombotic state. The pathogenesis differs from disseminated intravascular coagulation with a primary pulmonary localization. This is referred to as pulmonary intravascular coagulopathy with strong component of thrombo-inflammation. This is reflected in the lab tests with an increase in D-dimer which correlates with severity and outcomes of disease. Common coagulation tests such as prothrombin time, activated partial thromboplastin time are only mildly prolonged while most patients have normal to increased fibrinogen and marginal thrombocytopenia. Overall, the patients have an increase in venous and arterial thrombotic events especially in ICU patients. Routine thromboprophylaxis with low molecular weight heparin is recommended in all hospitalized patients to reduce the incidence of thrombosis. Bleeding is uncommon and treated with blood products transfusion. This review shall discuss the hemostatic abnormalities in COVID-19 patients and their impact on prognosis. In addition, strategy of thromboprophylaxis and various academic society guidelines are discussed in detail.

Extensive cerebral venous sinus thrombosis: a potential complication in a patient with COVID-19 disease

A 63-year-old man was admitted with left-sided weakness and subsequent focal seizures following a recent diagnosis of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia in a nearby hospital. He developed status epilepticus and became comatose, requiring intensive care unit admission for invasive ventilation. Imaging done at admission confirmed extensive cerebral venous sinus thrombosis (CVST) with bilateral venous cortical infarcts and acute cortical haemorrhage. No known risk factor for CVST could be identified. He improved with anticoagulation and antiepileptic therapy. He was subsequently transferred to an inpatient rehabilitation facility. Although Coronavirus disease 19 (COVID-19) infection has been previously associated with thrombotic complications, these mostly relate to the pulmonary vasculature. We present this case as a potential association between CVST and COVID-19 infection.

Oxygen-ozone (O2-O3) immunoceutical therapy for patients with COVID-19. Preliminary evidence reported

Objective

This study evaluated the potential efficacy of a novel approach to treat COVID-19 patients, using an oxygen-ozone (O₂-O₃) mixture, via a process called Oxygen-Ozone- Immunoceutical Therapy. The methodology met the criteria of a novel, promising approach to treat successfully elderly COVID-19 patients, particularly when hospitalized in intensive care units (ICUs) Experimental design: We investigated the therapeutic effect of 4 cycles of O₂-O₃ in 50 hospitalized COVID-19 subjects suffering from acute respiratory disease syndrome (ARDS), aged more than 60 years, all males and undergoing non invasive mechanical ventilation in ICUs.

Results

Following O₂-O₃ treatment a significant improvement in inflammation and oxygenation indexes occurred rapidly and within the first 9 days after the treatment, despite the expected 14–20 days. A significant reduction of inflammatory and thromboembolic markers (CRP, IL-6, D-dimer) was observed. Furthermore, amelioration in the major respiratory indexes, such as respiratory and gas exchange markers (SatO₂%, PaO₂/FiO₂ ratio), was reported.

Conclusion

Our results show that O₂-O₃ treatment would be a promising therapy for COVID-19 patients. It leads patients to a fast recovery from ARDS via the improvement of major respiratory indexes and blood gas parameters, following a relatively short time of dispensed forced ventilation (about one to two weeks). This study may encourage the scientific community to further investigate and evaluate the proposed method for the treatment of COVID-19 patients.

Central nervous system complications associated with SARS-CoV-2 infection: integrative concepts of pathophysiology and case reports

Coronavirus disease 2019 (COVID-19) is a highly infectious pandemic caused by a novel coronavirus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It frequently presents with unremitting fever, hypoxemic respiratory failure, and systemic complications (e.g., gastrointestinal, renal, cardiac, and hepatic involvement), encephalopathy, and thrombotic events. The respiratory symptoms are similar to those accompanying other genetically related beta-coronaviruses (CoVs) such as severe acute respiratory syndrome CoV (SARS-CoV) and Middle East Respiratory Syndrome CoV (MERS-CoV). Hypoxemic respiratory symptoms can rapidly progress to Acute Respiratory Distress Syndrome (ARDS) and secondary hemophagocytic lymphohistiocytosis, leading to multi-organ system dysfunction syndrome. Severe cases are typically associated with aberrant and excessive inflammatory responses. These include significant systemic upregulation of cytokines, chemokines, and pro-inflammatory mediators, associated with increased acute-phase proteins (APPs) production such as hyperferritinemia and elevated C-reactive protein (CRP), as well as lymphocytopenia. The neurological complications of SARS-CoV-2 infection are high among those with severe and critical illnesses. This review highlights the central nervous system (CNS) complications associated with COVID-19 attributed to primary CNS involvement due to rare direct neuroinvasion and more commonly secondary CNS sequelae due to exuberant systemic innate-mediated hyper-inflammation. It also provides a theoretical integration of clinical and experimental data to elucidate the pathogenesis of these disorders. Specifically, how systemic hyper-inflammation provoked by maladaptive innate immunity may impair neurovascular endothelial function, disrupt BBB, activate CNS innate immune signaling pathways, and induce para-infectious autoimmunity, potentially contributing to the CNS complications associated with SARS-CoV-2 infection. Direct viral infection of the brain parenchyma causing encephalitis, possibly with concurrent neurovascular endotheliitis and CNS renin angiotensin system (RAS) dysregulation, is also reviewed.

The Global Phosphorylation Landscape of SARS-CoV-2 Infection

The causative agent of the coronavirus disease 2019 (COVID-19) pandemic, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected millions and killed hundreds of thousands of people worldwide, highlighting an urgent need to develop antiviral therapies. Here we present a quantitative mass spectrometry-based phosphoproteomics survey of SARS-CoV-2 infection in Vero E6 cells, revealing dramatic rewiring of phosphorylation on host and viral proteins. SARS-CoV-2 infection promoted casein kinase II (CK2) and p38 MAPK activation, production of diverse cytokines, and shutdown of mitotic kinases, resulting in cell cycle arrest. Infection also stimulated a marked induction of CK2-containing filopodial protrusions possessing budding viral particles. Eighty-seven drugs and compounds were identified by mapping global phosphorylation profiles to dysregulated kinases and pathways. We found pharmacologic inhibition of the p38, CK2, CDK, AXL, and PIKFYVE kinases to possess antiviral efficacy, representing potential COVID-19 therapies.

D-Dimer Concentrations and COVID-19 Severity: A Systematic Review and Meta-Analysis

Coronavirus disease 2019 (COVID-19) is a recently described infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since late 2019, COVID-19 has rapidly spread in virtually all countries, imposing the adoption of significant lockdown and social distancing measures. The activation of the coagulation cascade is a common feature of disseminated intravascular coagulation and adverse clinical outcomes in COVID-19 patients. In this study, we conducted a meta-analysis aiming to investigate differences in serum D-dimer concentrations in patients with and without severe COVID-19 disease. An electronic search in Medline (PubMed), Scopus and Web of Science was performed with no language restrictions, and 13 articles were reporting on 1,807 patients (585, 32.4% with severe disease) were finally identified and included in the meta-analysis. The pooled results of all studies revealed that the D-dimer concentrations were significantly higher in patients with more severe COVID-19 (SMD: 0.91 mg/L; 95% CI, 0.75 to 1.07 mg/L, p < 0.0001). The heterogeneity was moderate (I2 = 46.5%; p = 0.033). Sensitivity analysis showed that the effect size was not modified when any single study was in turn removed (effect size range, 0.87 mg/L to 0.93 mg/L). The Begg's (p = 0.76) and Egger's tests (p = 0.38) showed no publication bias. In conclusion, our systematic review and meta-analysis showed that serum D-dimer concentrations in patients with severe COVID-19 are significantly higher when compared to those with non-severe forms.

Orbital cellulitis, sinusitis and intracranial abnormalities in two adolescents with COVID-19

We review two cases of adolescents with orbital cellulitis, sinusitis and SARS- CoV-2 infection presenting to emergency departments within a 24 hour period. SARS-CoV-2 samples obtained within 24 hours were positive, supporting prior infection despite relatively limited early symptoms of COVID-19. Unusual clinical and radiographic characteristics included hemorrhagic abscess with blood of varying age in the first, intracranial epidural abscess in the second, radiographic signal consistent with hemorrhagic or thrombotic phenomena, retro-maxillary antral fat changes, and meningeal enhancement or extension in both cases. Radiographic findings thereby mimic fungal infection, although final cultures and ancillary investigation for allergic and invasive fungal disease have remained negative. These cases highlight two unusual orbital presentations of cellulitis occurring in the context of SARS-CoV-2 co-infection.

Managing anticoagulation in the COVID-19 era between lockdown and reopening phases

Patients on anticoagulant treatment are constantly increasing, with an estimated prevalence in Italy of 2% of the total population. The recent spreadout of the COVID-19 pandemic requires a re-organization of Anticoagulation Clinics to prevent person-to-person viral diffusion and continue to offer the highest possible quality of assistance to patients. In this paper, based on the Italian Federation of Anticoagulation Clinics statements, we offer some advice aimed at improving patient care during COVID-19 pandemic, with particular regard to the lockdown and reopening periods. We give practical guidance regarding the following points: (1) re-thinking the AC organization, (2) managing patients on anticoagulants when they become infected by the virus, (3) managing anticoagulation surveillance in non-infected patients during the lockdown period, and (4) organizing the activities during the reopening phases.

Macrothrombosis and stroke in patients with mild Covid-19 infection

Coronavirus disease 2019 (COVID-19) is a pandemic disease currently affecting millions of people worldwide. Its neurological implications are poorly understood, and further study is urgently required. A hypercoagulable state has been reported in patients with severe COVID-19, but nothing is known about coagulopathy in patients with milder disease. We describe cases of patients in New York City presenting with stroke secondary to large vessel thrombosis without occlusion, incidentally found to have COVID-19 with only mild respiratory symptoms. This is in contrast to the venous thrombosis and microangiopathy that has been reported in patients with severe COVID-19. Our cases suggest that even in the absence of severe disease, patients with COVID-19 may be at increased risk of thrombus formation leading to stroke, perhaps resulting from viral involvement of the endothelium. Further systematic study is needed because this may have implications for primary and secondary stroke prevention in patients with COVID-19.

Managing anticoagulation in the COVID-19 era between lockdown and reopening phases

Patients on anticoagulant treatment are constantly increasing, with an estimated prevalence in Italy of 2% of the total population. The recent spreadout of the COVID-19 pandemic requires a re-organization of Anticoagulation Clinics to prevent person-to-person viral diffusion and continue to offer the highest possible quality of assistance to patients. In this paper, based on the Italian Federation of Anticoagulation Clinics statements, we offer some advice aimed at improving patient care during COVID-19 pandemic, with particular regard to the lockdown and reopening periods. We give practical guidance regarding the following points: (1) re-thinking the AC organization, (2) managing patients on anticoagulants when they become infected by the virus, (3) managing anticoagulation surveillance in non-infected patients during the lockdown period, and (4) organizing the activities during the reopening phases.

Pulmonary Thromboembolism in COVID-19: Venous Thromboembolism or Arterial Thrombosis?

PURPOSE

To investigate CT pulmonary angiography findings of pulmonary thromboembolism (PTE) in coronavirus disease 2019 (COVID-19) and its association with clinical and radiologic conditions.

MATERIALS AND METHODS

This retrospective study includes 109 hospitalized patients with COVID-19 who underwent CT pulmonary angiography for suspected PTE from March 20 to May 3, 2020. Data were collected from our PACS. CT pulmonary angiography findings of PTE were evaluated. On the basis of the presence or absence of PTE, patients were divided into two groups, and their clinical and radiologic conditions were compared using the Mann-Whitney U test and χ2 test.

RESULTS

The study population comprised 82 men and 19 women, with a mean age of 64.1 years ± 15.0 (95% confidence interval [CI]: 60.4, 67.6) years. CT pulmonary angiography was performed 19.8 days ± 6.1 (95% CI: 18.1, 20.2) after symptom onset and 10.5 days ± 3.8 (95% CI: 10.2, 12.9) after admission. Of 101 patients, 41 had PTE (40.6%). PTE was mostly bilateral or only right (37/41 [90.2%]), mainly involved segmental (37/41 [90.2%]) or subsegmental (25/41 [61.0%]) arteries and affected mainly the branches of the lower lobe (30/41 [73.2%]). Parenchymal segments supplied by segmental arteries with PTE showed a prevalent consolidation pattern (25/37 [67.6%]). Deep vein thrombosis was present only in five of 41 (12.2%) patients. Comparing groups with and without PTE, no significant difference was observed in age, sex, symptom onset, comorbidities, tumor history, use of respiratory supports, activated partial thromboplastin time, prothrombin time, and deep vein thrombosis. Conversely, differences were evaluated in CT lesion score (15.7 ± 1.4 [95% CI: 15.3, 16.1] vs 14.1 ± 1.1 [95% CI: 13.8, 14.4]; P = .035), d-dimer level (P < .001), lactate dehydrogenase level (P < .001), and C-reactive protein level (P = .042).

CONCLUSION

PTE in COVID-19 involves mainly the segmental and subsegmental arteries of segments affected by consolidations in patients with more severe lung disease. The authors hypothesize that the development of PTE in COVID-19 might be a pulmonary artery thrombosis because of severe lung inflammation and hypercoagulability rather than thromboembolism.© RSNA, 2020.

Cerebral Venous Thrombosis Associated with COVID-19

Despite the severity of coronavirus disease 2019 (COVID-19) being more frequently related to acute respiratory distress syndrome and acute cardiac and renal injuries, thromboembolic events have been increasingly reported. We report a unique series of young patients with COVID-19 presenting with cerebral venous system thrombosis. Three patients younger than 41 years of age with confirmed Severe Acute Respiratory Syndrome coronavirus 2 (SARS-Cov-2) infection had neurologic findings related to cerebral venous thrombosis. They were admitted during the short period of 10 days between March and April 2020 and were managed in an academic institution in a large city. One patient had thrombosis in both the superficial and deep systems; another had involvement of the straight sinus, vein of Galen, and internal cerebral veins; and a third patient had thrombosis of the deep medullary veins. Two patients presented with hemorrhagic venous infarcts. The median time from COVID-19 symptoms to a thrombotic event was 7 days (range, 2-7 days). One patient was diagnosed with new-onset diabetic ketoacidosis, and another one used oral contraceptive pills. Two patients were managed with both hydroxychloroquine and azithromycin; one was treated with lopinavir-ritonavir. All patients had a fatal outcome. Severe and potentially fatal deep cerebral thrombosis may complicate the initial clinical presentation of COVID-19. We urge awareness of this atypical manifestation.

Understanding the epidemiology, pathophysiology, diagnosis and management of SARS-CoV-2

The emergence of coronavirus disease 2019 (COVID-19) in December 2019 has resulted in over 20 million cases and 741,808 deaths globally, affecting more than 200 countries. COVID-19 was declared a pandemic on 11 March 2020 by the World Health Organization. The disease is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). There is limited information on COVID-19, and treatment has so far focused on supportive care and use of repurposed drugs. COVID-19 can be transmitted via person-to-person contact through droplet spread. Some of the recommended precautionary measures to reduce the rate of disease spread include social distancing, good hygiene practices, and avoidance of crowded areas. These measures are effective because the droplets are heavy and can only travel approximately 1 meter in the air, settling quickly on fixed surfaces. Promising strategies to combat SARS-CoV-2 include discovery of therapeutic targets/drugs and vaccines. In this review, we summarize the epidemiology, pathophysiology, and diagnosis of COVID-19. We also address the mechanisms of action of approved repurposed drugs for therapeutic management of the disease.

Overcoming Barriers: The Endothelium As a Linchpin of Coronavirus Disease 2019 Pathogenesis?

OBJECTIVE

Coronavirus disease 2019 (COVID-19) is a global pandemic involving >5 500 000 cases worldwide as of May 26, 2020. The culprit is the severe acute respiratory syndrome coronavirus-2, which invades cells by binding to ACE2 (angiotensin-converting enzyme 2). While the majority of patients mount an appropriate antiviral response and recover at home, others progress to respiratory distress requiring hospital admission for supplemental oxygen. In severe cases, deterioration to acute respiratory distress syndrome necessitating mechanical ventilation, development of severe thrombotic events, or cardiac injury and dysfunction occurs. In this review, we highlight what is known to date about COVID-19 and cardiovascular risk, focusing in on the putative role of the endothelium in disease susceptibility and pathogenesis. Approach and Results: Cytokine-driven vascular leak in the lung alveolar-endothelial interface facilitates acute lung injury in the setting of viral infection. Given that the virus affects multiple organs, including the heart, it likely gains access into systemic circulation by infecting or passing from the respiratory epithelium to the endothelium for viral dissemination. Indeed, cardiovascular complications of COVID-19 are highly prevalent and include acute cardiac injury, myocarditis, and a hypercoagulable state, all of which may be influenced by altered endothelial function. Notably, the disease course is worse in individuals with preexisting comorbidities that involve endothelial dysfunction and may be linked to elevated ACE2 expression, such as diabetes mellitus, hypertension, and cardiovascular disease.

CONCLUSIONS

Rapidly emerging data on COVID-19, together with results from studies on severe acute respiratory syndrome coronavirus-1, are providing insight into how endothelial dysfunction may contribute to the pandemic that is paralyzing the globe. This may, in turn, inform the design of biomarkers predictive of disease course, as well as therapeutics targeting pathogenic endothelial responses.

Patient blood management during the COVID-19 pandemic: a narrative review

As COVID-19 disease escalates globally, optimising patient outcome during this catastrophic healthcare crisis is the number one priority. The principles of patient blood management are fundamental strategies to improve patient outcomes and should be given high priority in this crisis situation. The aim of this expert review is to provide clinicians and healthcare authorities with information regarding how to apply established principles of patient blood management during the COVID-19 pandemic. In particular, this review considers the impact of the COVID-19 pandemic on blood supply and specifies important aspects of donor management. We discuss how preventative and control measures implemented during the COVID-19 crisis could affect the prevalence of anaemia, and highlight issues regarding the diagnosis and treatment of anaemia in patients requiring elective or emergency surgery. In addition, we review aspects related to patient blood management of critically ill patients with known or suspected COVID-19, and discuss important alterations of the coagulation system in patients hospitalised due to COVID-19. Finally, we address special considerations pertaining to supply-demand and cost-benefit issues of patient blood management during the COVID-19 pandemic.

The SARS-CoV-2 receptor, ACE-2, is expressed on many different cell types: implications for ACE-inhibitor- and angiotensin II receptor blocker-based cardiovascular therapies

SARS-CoV-2 is characterized by a spike protein allowing viral binding to the angiotensin-converting enzyme (ACE)-2, which acts as a viral receptor and is expressed on the surface of several pulmonary and extra-pulmonary cell types, including cardiac, renal, intestinal and endothelial cells. There is evidence that also endothelial cells are infected by SARS-COV-2, with subsequent occurrence of systemic vasculitis, thromboembolism and disseminated intravascular coagulation. Those effects, together with the "cytokine storm" are involved in a worse prognosis. In clinical practice, angiotensin-converting enzyme inhibitors (ACE-Is) and angiotensin II receptor blockers (ARBs) are extensively used for the treatment of hypertension and other cardiovascular diseases. In in vivo studies, ACE-Is and ARBs seem to paradoxically increase ACE-2 expression, which could favour SARS-CoV-2 infection of host's cells and tissues. By contrast, in patients treated with ACE-Is and ARBs, ACE-2 shows a downregulation at the mRNA and protein levels in kidney and cardiac tissues. Yet, it has been claimed that both ARBs and ACE-Is could result potentially useful in the clinical course of SARS-CoV-2-infected patients. As detected in China and as the Italian epidemiological situation confirms, the most prevalent comorbidities in deceased patients with COVID-19 are hypertension, diabetes and cardiovascular diseases. Older COVID-19-affected patients with cardiovascular comorbidities exhibit a more severe clinical course and a worse prognosis, with many of them being also treated with ARBs or ACE-Is. Another confounding factor is cigarette smoking, which has been reported to increase ACE-2 expression in both experimental models and humans. Sex also plays a role, with chromosome X harbouring the gene coding for ACE-2, which is one of the possible explanations of why mortality in female patients is lower. Viral entry also depends on TMPRSS2 protease activity, an androgen dependent enzyme. Despite the relevance of experimental animal studies, to comprehensively address the question of the potential hazards or benefits of ACE-Is and ARBs on the clinical course of COVID-19-affected patients treated by these anti-hypertensive drugs, we will need randomized human studies. We claim the need of adequately powered, prospective studies aimed at answering the following questions of paramount importance for cardiovascular, internal and emergency medicine: Do ACE-Is and ARBs exert similar or different effects on infection or disease course? Are such effects dangerous, neutral or even useful in older, COVID-19-affected patients? Do they act on multiple cell types? Since ACE-Is and ARBs have different molecular targets, the clinical course of SARS-CoV-2 infection could be also different in patients treated by one or the other of these two drug classes. At present, insufficient detailed data from trials have been made available.

SEDAR-SEMICYUC consensus recommendations on the management of haemostasis disorders in severely ill patients with COVID-19 infection

The infection by the coronavirus SARS-CoV-2, which causes the disease called COVID-19, mainly causes alterations in the respiratory system. In severely ill patients, the disease often evolves into an acute respiratory distress syndrome that can predispose patients to a state of hypercoagulability, with thrombosis at both venous and arterial levels. This predisposition presents a multifactorial physiopathology, related to hypoxia as well as to the severe inflammatory process linked to this pathology, including the additional thrombotic factors present in many of the patients.

In view of the need to optimise the management of hypercoagulability, the working groups of the Scientific Societies of Anaesthesiology-Resuscitation and Pain Therapy (SEDAR) and of Intensive, Critical Care Medicine and Coronary Units (SEMICYUC) have developed a consensus to establish guidelines for actions to be taken against alterations in haemostasis observed in severely ill patients with COVID-19. These recommendations include prophylaxis of venous thromboembolic disease in these patients, and in the peripartum, management of patients on long-term antiplatelet or anticoagulant treatment, bleeding complications in the course of the disease, and the interpretation of general alterations in haemostasis.

Cardiovascular manifestations and treatment considerations in COVID-19

Since its recognition in December 2019, covid-19 has rapidly spread globally causing a pandemic. Pre-existing comorbidities such as hypertension, diabetes, and cardiovascular disease are associated with a greater severity and higher fatality rate of covid-19. Furthermore, COVID-19 contributes to cardiovascular complications, including acute myocardial injury as a result of acute coronary syndrome, myocarditis, stress-cardiomyopathy, arrhythmias, cardiogenic shock, and cardiac arrest. The cardiovascular interactions of COVID-19 have similarities to that of severe acute respiratory syndrome, Middle East respiratory syndrome and influenza. Specific cardiovascular considerations are also necessary in supportive treatment with anticoagulation, the continued use of renin-angiotensin-aldosterone system inhibitors, arrhythmia monitoring, immunosuppression or modulation, and mechanical circulatory support.