Pulmonary thrombosis in 2019-nCoV pneumonia?

A journey to vasculopathy in systemic sclerosis: focus on haemostasis and thrombosis

Systemic sclerosis is a multisystem connective tissue disease, characterized by endothelial autoimmune activation, along with tissue and vascular fibrosis leading to vasculopathy and to a progressive loss of angiogenesis. This condition further deranges the endothelial barrier favouring the opening of the endothelial junctions allowing the vascular leak in the surrounding tissues: this process may induce cell detachment which allows the contact between platelets and collagen present in the exposed subendothelial layer. Platelets first adhere to collagen via glycoprotein VI and then, immediately aggregate because of the release of von Willebrand factor which is a strong activator of platelet aggregation. Activated platelets exert their procoagulant activity, exposing on their membrane phospholipids and phosphatidylserine, enabling the adsorption of clotting factors ready to form thrombin which in turn drives the amplification of the coagulative cascade. An essential role in the activation of blood coagulation is the tissue factor (TF), which triggers blood coagulation. The TF is found abundantly in the subendothelial collagen and is also expressed by fibroblasts providing a haemostatic covering layer ready to activate coagulation when the endothelial injury occurs. The aim of this review is to focus the attention on the underlying mechanisms related to haemostasis and thrombosis pathophysiology which may have a relevant role in SSc as well as on a possible role of anticoagulation in this disease.

The impact of daily troponin I and D-dimer serum levels on mortality in COVID-19 pneumonia patients

BACKGROUND

Coronavirus disease 2019 (COVID-19) is an infection resulting in very high morbidity and mortality rates globally. Limited data are available on the cardiovascular manifestations in these patients. The aim of this study was to analyse the daily troponin I and D-dimer levels and their impact on the need for intensive care and on mortality rates of COVID-19-infected patients.

METHODS

Two-hundred and five patients who were hospitalised between 20 March and 5 May 2020, with a diagnosis of moderate-to-severe COVID-19 pneumonia, were analysed retrospectively. Serum troponin I and D-dimer levels were recorded for at least 10 days after admission.

RESULTS

The average age was higher in the group of patients who died compared to the group who were discharged (67.79 ± 14.9 vs 56.87 ± 18.15 years, respectively, p < 0.001). The presence of hypertension, diabetes mellitus, previous coronary bypass surgery, heart failure, chronic renal failure and chronic obstructive pulmonary disease statistically significantly affected mortality rates (p = 0.003, 0.004, 0.045, 0.02, 0.003, 0.007, respectively). The first 10 days of measurements of troponin I and D-dimer were associated with intensive care requirements and mortality (p < 0.001). Both troponin I and D-dimer were higher in the group who died compared to the patients requiring intensive care. Troponin I values of ≥ 16.05 pg/ml on the seventh day were related to the need for intensive care [area under the curve (AUC) 0.896, sensitivity 78.6%, specificity 78.3%, p < 0.001). Troponin I values ≥ 30.25 pg/ml on the ninth day were related to mortality (AUC 0.920, sensitivity 89.5%, specificity 89.3%, p < 0.001). D-dimer values ≥ 878 hg/ml on the second day were associated with intensive care need (AUC 0.896, sensitivity 78.6%, specificity 78.3%, p < 0.001). D-dimer values ≥ 1 106 hg/ml on the 10th day were associated with mortality (AUC 0.817, sensitivity 68.4%, specificity 65.2%, p < 0.001). It was observed that hospitalisation periods ≥ 9.5 days were associated with mortality (AUC 0.738, sensitivity 68.4%, specificity 65.9%, p < 0.001).

CONCLUSIONS

We showed that hospitalisations ≥ 9.5 days in duration were related to increased mortality rates. Troponin I and D-dimer follow-up values in the serum were more effective than other inflammatory markers in predicting mortality and the need for intensive care. A high troponin I value should alert the clinician in terms of clinical deterioration.

Investigation of Pulmonary Artery and Ascending Aorta Morphology in the Coronavirus Disease 2019: A Radioanatomical Study

OBJECTIVE

This study aimed to determine the maximum diameters of the pulmonary artery and ascending aorta and their ratio to each other to enable early diagnosis and treatment of possible pulmonary hypertension and to prevent possible complications in patients infected with severe acute respiratory syndrome coronavirus 2.

MATERIAL AND METHODS

A total of 120 patients aged 40 years and older, 60 patients (30 females and 30 males) with severe acute respiratory syndrome coronavirus 2 infection and 60 individuals (30 females and 30 males), were included in this retrospective study. Maximum pulmonary artery and maximum ascending aorta diameters were measured at the level of bifurcatio trunci pulmonalis in the transverse axial plane by computed tomography, and their ratios to each other were determined.

RESULTS

Our study revealed a statistically significant increase in maximum pulmonary artery and maximum ascending aorta diameters in both genders in patients with coronavirus disease 2019 compared to the control group and a statistically significant increase was found in the maximum pulmonary artery-maximum ascending aorta ratio in women with coronavirus disease 2019 compared to the control group (P < .05).

CONCLUSIONS

Knowing the diameters of maximum pulmonary artery and maximum ascending aorta and the maximum pulmonary artery-maximum ascending aorta ratio in hospitalized severe acute respiratory syndrome coronavirus 2-infected patients is a valuable predictive marker of pulmonary hypertension and a guide in determining the appropriate treatment. These data, which are easy to calculate from thorax computed tomography, may be beneficial in the prognosis of the disease.

The Dual Pandemics of COVID-19 and Obesity: Bidirectional Impact

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), responsible for the COVID-19 pandemic, has been shown to disrupt many organ systems in the human body. Though several medical disorders have been affected by this infection, a few illnesses in addition may also play a role in determining the outcome of COVID-19. Obesity is one such disease which is not only affected by the occurrence of COVID-19 but can also result in a worse clinical outcome of COVID-19 infection. This manuscript summarizes the most recent evidence supporting the bidirectional impact of COVID-19 and obesity. It highlights how the presence of obesity can be detrimental to the outcome of COVID-19 in a given patient because of the mechanical limitations in lung compliance and also by the activation of several thrombo-inflammatory pathways. The sociodemographic changes brought about by the pandemic in turn have facilitated the already increasing prevalence of obesity. This manuscript highlights the importance of recognizing these pathways which may further help in policy changes that facilitate appropriate measures to prevent the further worsening of these two pandemics.

COVID-19 and the potential of Janus family kinase (JAK) pathway inhibition: A novel treatment strategy

Recent evidence proposed that the severity of the coronavirus disease 2019 (COVID-19) in patients is a consequence of cytokine storm, characterized by increased IL-1β, IL-6, IL-18, TNF-α, and IFN-γ. Hence, managing the cytokine storm by drugs has been suggested for the treatment of patients with severe COVID-19. Several of the proinflammatory cytokines involved in the pathogenesis of COVID-19 infection recruit a distinct intracellular signaling pathway mediated by JAKs. Consequently, JAK inhibitors, including baricitinib, pacritinib, ruxolitinib, and tofacitinib, may represent an effective therapeutic strategy for controlling the JAK to treat COVID-19. This study indicates the mechanism of cytokine storm and JAK/STAT pathway in COVID-19 as well as the medications used for JAK/STAT inhibitors.

Pharmacotherapy consideration of thrombolytic medications in COVID-19-associated ARDS

BACKGROUND

In late 2019, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which is responsible for coronavirus disease (COVID-19), was identified as the new pathogen to lead pneumonia in Wuhan, China, which has spread all over the world and developed into a pandemic. Despite the over 1 year of pandemic, due to the lack of an effective treatment plan, the morbidity and mortality of COVID-19 remains high. Efforts are underway to find the optimal management for this viral disease.

MAIN BODY

SARS-CoV-2 could simultaneously affect multiple organs with variable degrees of severity, from mild to critical disease. Overproduction of pro-inflammatory mediators, exacerbated cellular and humoral immune responses, and coagulopathy such as Pulmonary Intravascular Coagulopathy (PIC) contributes to cell injuries. Considering the pathophysiology of the disease and multiple microthrombi developments in COVID-19, thrombolytic medications seem to play a role in the management of the disease. Beyond the anticoagulation, the exact role of thrombolytic medications in the management of patients with COVID-19-associated acute respiratory distress syndrome (ARDS) is not explicit. This review focuses on current progress in underlying mechanisms of COVID-19-associated pulmonary intravascular coagulopathy, the historical use of thrombolytic drugs in the management of ARDS, and pharmacotherapy considerations of thrombolytic therapy, their possible benefits, and pitfalls in COVID-19-associated ARDS.

CONCLUSIONS

Inhaled or intravenous administration of thrombolytics appears to be a salvage therapy for severe ARDS associated with COVID-19 by prompt attenuation of lung injury. Considering the pathogenesis of COVID-19-related ARDS and mechanism of action of thrombolytic agents, thrombolytics appear attractive options in stable patients without contraindications.

Haemostatic differences between SARS-CoV-2 PCR-positive and negative patients at the time of hospital admission

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is associated with thrombosis. We conducted a cohort study of consecutive patients, suspected of SARS-CoV-2 infection presented to the emergency department. We investigated haemostatic differences between SARS-CoV-2 PCR positive and negative patients, with dedicated coagulation analysis. The 519 included patients had a median age of 66 years, and 52.5% of the patients were male. Twenty-six percent of the patients were PCR-positive for SARS-CoV-2.PCR positive patients had increased levels of fibrinogen and (active) von Willebrand Factor (VWF) and decreased levels of protein C and α2-macroglobulin compared to the PCR negative patients. In addition, we found acquired activated protein C resistance in PCR positive patients. Furthermore, we found that elevated levels of factor VIII and VWF and decreased levels of ADAMTS-13 were associated with an increased incidence of thrombosis in PCR positive patients. In conclusion, we found that PCR positive patients had a pronounced prothrombotic phenotype, mainly due to an increase of endothelial activation upon admission to the hospital. These findings show that coagulation tests may be considered useful to discriminate severe cases of COVID-19 at risk for thrombosis.

A review of COVID-19: Treatment strategies and CRISPR/Cas9 gene editing technology approaches to the coronavirus disease

The new coronavirus SARS-CoV-2 pandemic has put the world on lockdown for the first time in decades. This has wreaked havoc on the global economy, put additional burden on local and global public health resources, and, most importantly, jeopardised human health. CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats, and the CRISPR associated (Cas) protein (CRISPR/Cas) was identified to have structures in E. coli. The most modern of these systems is CRISPR/Cas. Editing the genomes of plants and animals took several years and cost hundreds of thousands of dollars until the CRISPR approach was discovered in 2012. As a result, CRISPR/Cas has piqued the scientific community's attention, particularly for disease diagnosis and treatment, because it is faster, less expensive, and more precise than previous genome editing technologies. Data from gene mutations in specific patients gathered using CRISPR/Cas can aid in the identification of the best treatment strategy for each patient, as well as other research domains such as coronavirus replication in cell culture, such as SARS-CoV2. The implications of the most prevalent driver mutations, on the other hand, are often unknown, making treatment interpretation difficult. For detecting a wide range of target genes, the CRISPR/Cas categories provide highly sensitive and selective tools. Genome-wide association studies are a relatively new strategy to discovering genes involved in human disease when it comes to the next steps in genomic research. Furthermore, CRISPR/Cas provides a method for modifying non-coding portions of the genome, which will help advance whole genome libraries by speeding up the analysis of these poorly defined parts of the genome.

The association between the CT severity index and the pulmonary artery area in COVID-19 pneumonia

BACKGROUND

The pulmonary artery area (PAA) is a valuable non-invasive method for the diagnosis of pulmonary hypertension.

PURPOSE

To compare the change in PAA in patients with COVID-19 with the computed tomography (CT) severity index using follow-up imaging.

MATERIAL AND METHODS

A total of 81 patients who were followed up and underwent CT assessment more than once at our hospital's pandemic department were evaluated retrospectively. Patients with progression were separated into three groups: progression ranging from mild-to-mild infiltration (Group A, CT severity index of 0-2); progression from mild to severe infiltration (Group B, CT severity index of 0-2 to 3-5); and progression from severe-to-severe infiltration (Group C, CT severity index of 3-5). The PAAs were calculated separately.

RESULTS

The mean age was 56 ± 12 years. In terms of those patients showing progression in the CT images, the number of patients in Groups A, B, and C was 29, 40, and 12 in the right lung; 32, 45, and 4 in the left lung; 23, 45, and 13 on both lungs, respectively. There was no significant difference between the main, right, and left PAAs in Group A (P > 0.05). In Group B, there were significant increases in the areas of the main, right, and left PAAs (P < 0.05). There were also significant increases in the areas of the right and main pulmonary arteries in Group C (P < 0.05).

CONCLUSION

PAAs increase as disease involvement advances in cases with COVID-19 pneumonia, which is thought to be correlated with progression.

Upper extremity deep vein thrombosis in COVID-19: Incidence and correlated risk factors in a cohort of non-ICU patients

Background

Venous thromboembolism is a frequent complication of COVID-19 infection. Less than 50% of pulmonary embolism (PE) is associated with the evidence of deep venous thrombosis (DVT) of the lower extremities. DVT may also occur in the venous system of the upper limbs especially if provoking conditions are present such as continuous positive airway pressure (CPAP). The aim of this study was to evaluate the incidence of UEDVT in patients affected by moderate-severe COVID-19 infection and to identify potential associated risk factors for its occurrence.

Methods

We performed a retrospective analysis of all patients affected by moderate-severe COVID-19 infection admitted to our unit. In accordance with the local protocol, all patients had undergone a systematic screening for the diagnosis of UEDVT, by vein compression ultrasonography (CUS). All the patients were receiving pharmacological thromboprophylaxis according to international guidelines recommendations. Univariate and multivariate analyses were used to identify risk factors associated with UEDVT.

Results

257 patients were included in the study, 28 patients were affected by UEDVT with an incidence of 10.9% (95% CI, 7.1–14.7). At univariate analysis UEDVT appeared to be significantly associated (p< 0.05) with pneumonia, ARDS, PaO2/FiO2, D-dimer value higher than the age adjusted cut off value and need for CPAP ventilation. Multivariate analysis showed a significant association between UEDVT and the need for CPAP ventilation (OR 5.95; 95% IC 1.33–26.58). Increased mortality was found in patients affected by UEDVT compared to those who were not (OR 3.71; 95% CI, 1.41–9.78).

Conclusions

UEDVT can occur in COVID-19 patients despite adequate prophylaxis especially in patients undergoing helmet CPAP ventilation. Further studies are needed to identify the correct strategy to prevent DVT in these patients.

Trombosis y COVID-19: revisión de alcance

La enfermedad por coronavirus COVID-19 ha generado la mayor crisis de salud pública de la era moderna. Se considera que el estado protrombótico inducido por la infección tiene una relación directa y de importancia sustancial con el daño agudo en el pulmón y con las complicaciones de la infección, incluida la muerte. Esta revisión de alcance (scoping review) resume y evalúa críticamente la evidencia sobre la relación entre la trombosis y la COVID-19, y se basa en una búsqueda bibliográfica sistemática de todos los artículos publicados hasta el 5 de mayo de 2020 e incluidos en las bases de datos PubMed, Scopus, Cochrane y Clinicaltrials.gov. Hemos incluido 26 artículos en la revisión, y hemos evaluado su calidad empleando la guía STROBE. Los principales síntomas que presentan los pacientes diagnosticados con COVID-19 son disnea, fiebre, tos, diarrea y vómitos. A nivel analítico destaca, en esta enfermedad, un aumento de dímero-D, fibrinógeno, tiempo de protrombina y linfopenia. En cuanto a las pruebas radiológicas, las técnicas más usadas para el diagnóstico de tromboembolismo pulmonar, trombosis venosa profunda y otros fenómenos trombóticos fueron la ecografía y la tomografía computarizada. Como conclusión, en la actualidad existe escasa evidencia científica con respecto a la COVID-19 y sus complicaciones trombóticas. Esta revisión resume este cuerpo de evidencia, evalúa su calidad, y ofrece conclusiones que orientan los siguientes pasos a dar en este área de investigación de enorme relevancia y crecimiento exponencial.

NEUT-SFL in Patients with COVID-ARDS: A Novel Biomarker for Thrombotic Events?

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an enveloped RNA virus first identified in December 2019 in Wuhan, China, and responsible for coronavirus disease 2019 (COVID-19). The ongoing COVID-19 pandemic is impacting healthcare worldwide. Patients who develop coagulopathy have worse outcomes. The pathophysiology of COVID-19 suggests a strong interplay between hemostasis and immune cells, especially neutrophils. Our purpose was to assess neutrophil fluorescence as a potential biomarker of deep vein thrombosis (DVT) in patients with COVID-acute respiratory distress syndrome (COVID-ARDS). Sixty-one patients with COVID-ARDS admitted to the four intensive care units (ICUs) of a French general hospital were included in this prospective study. Neutrophil activation was assessed by measuring neutrophil fluorescence (NEUT-Side Fluorescence Light, NEUT-SFL) with a specific fluorescent dye staining analyzed by a routine automated flow cytometer Sysmex XN-3000™ (Sysmex, Kobe, Japan). DVT was diagnosed by complete duplex ultrasound (CDU). We found that NEUT-SFL was elevated on admission in patients with COVID-ARDS (49.76 AU, reference value 46.40 AU, p < 0.001), but did not differ between patients with DVT (49.99 AU) and those without (49.52 AU, p = 0.555). NEUT-SFL is elevated in patients with COVID-ARDS, reflecting neutrophil activation, but cannot be used as a marker of thrombosis. Because neutrophils are at interface between immune response and hemostasis through release of neutrophil extracellular traps, monitoring their activation could be an interesting approach to improve our management of coagulopathy during COVID-ARDS. Further research is needed to better understand the pathophysiology of COVID-19 and identify high-performance biomarkers.

COVID-19 and obesity: the meeting of two pandemics

COVID-19 and obesity are two pandemic diseases that the world is currently facing. Both activate the immune system and mediate inflammation. A sequence of disease phases in patients with severe COVID-19 results in a cytokine storm, which amplifies the subclinical inflammation that already exists in patients with obesity. Pro-inflammatory cytokines and chemotactic factors increase insulin resistance in obesity. Therefore, a greater systemic inflammatory response is establishe, along with an increased risk of thrombotic phenomena and hyperglycemic conditions. These changes further impair pulmonary, cardiac, hepatic, and renal functions, in addition to hindering glycemic control in people with diabetes and pre-diabetes. This review explains the pathophysiological mechanisms of these two pandemic diseases, provides a deeper understanding of this harmful interaction and lists possible therapeutic strategies for this risk group.

Venous thromboembolism in patients with COVID-19 infection: risk factors, prevention, and management

Venous thromboembolic complications have emerged as serious sequelae in COVID-19 infections. This article summarizes the most current information regarding pathophysiology, risk factors and hematologic markers, incidence and timing of events, atypical venous thromboembolic complications, prophylaxis recommendations, and therapeutic recommendations. Data will likely to continue to rapidly evolve as more knowledge is gained regarding venous events in COVID-19 patients.

Association between Hypomagnesemia, COVID-19, Respiratory Tract and Lung Disease

The complexity of COVID-19 is also related to the multiple molecular pathways triggered by SARS-CoV-2, which is able to cause type I pneumocyte death, trigger intravascular coagulation, interfere with the renin-angiotensin system, dysregulate iron metabolism, ending with the insurgence of a cytokine storm which may lead to death. Old adults with obesity, hypertension, and diabetes are among the high-risk category groups more prone to SARS-CoV-2 infection. Magnesium has been reported to play a major role both in physiology and in pathology, particularly in elderly people, regulating cytotoxic functions of natural killer (NK) cells and CD8+ T lymphocytes. In spite of the absence of controlled trials, the possibility of magnesium supplementation for supportive treatment in patients with COVID-19 should be encouraged. This could be useful in all phases of the COVID-19 disease.

High immature platelet fraction with reduced platelet count on hospital admission. Can it be useful for COVID-19 diagnosis?

Introduction

Health professions are heavily engaged facing the current threat of SARS‐CoV‐2 (COVID‐19). Although there are many diagnostic tools, an accurate and rapid laboratory procedure for diagnosing COVID‐19 is recommended. We focused on platelet parameters as the additional biomarkers for clinical diagnosis in patients presenting to the emergency department (ED).

Materials and Methods

Five hundred and sixty‐one patients from February to April 2020 have been recruited. Patients were divided into three groups: (N = 50) COVID‐19 positive and (N = 21) COVID‐19 negative with molecular testing, (N = 490) as reference population without molecular testing. A Multiplex rRT‐PCR from samples collected by nasopharyngeal swabs was performed and the hematological data collected.

Results

We detected a mild anemia in COVID‐19 group and lymphopenia against reference population: hemoglobin (g/dL) 13.0 (11.5‐14.8) versus 13.9 (12.8‐15.0) (P = .0135); lymphocytes (10⁹/L) 1.24 (0.94‐1.73) versus 1.99 (1.49‐2.64) (P < .0001). In addition, abnormal platelet parameters as follows (COVID group vs reference population): PLT (×10⁹/L) 209 (160‐258) vs 236 (193‐279) (P = .0239). IPF (%) 4.05 (2.5‐5.9) versus 3.4 (2.2‐4.9) (P = .0576); H‐IPF (%) 1.25 (0.8‐2.2) versus 0.95 (0.6‐1.5) (P = .0171) were identified. In particular, COVID positive group had a high H‐IPF/IPF Ratio compared to reference population [0.32 (0.29‐0.36) versus 0.29 (0.26‐0.32), respectively, (P = .0003)]. Finally, a PLT difference of nearly 50 × 10⁹/L between pre/postCOVID‐19 sampling for each patient was found (N = 42) (P = .0194).

Conclusions

COVID‐19 group results highlighted higher IPF and H‐IPF values, with increased H‐IPF/IPF Ratio, associated to PLT count reduction. These findings shall be adopted for a timely diagnosis of patients upon hospital admission.

Neurological manifestations of COVID-19 in patients: from path physiology to therapy

Coronavirus is a family of ARN positive single-stranded belonging to the family of Coronaviridae. There are several families of coronavirus that transmit more or less serious diseases. However, the so-called coronavirus-19 (SARS-CoV2) is the one that is currently causing most of the problems; in fact, biological dysfunctions that this virus causes provoke damage in various organs, from the lung to the heart, the kidney, the circulatory system, and even the brain. The neurological manifestations caused by viral infection, as well as the hypercoagulopathy and systemic inflammation, have been reported in several studies. In this review, we update the neurological mechanisms by which coronavirus-19 causes neurological manifestation in patients such as encephalomyelitis, Guillain-Barré syndrome, lacunars infarcts, neuropsychiatry disorders such as anxiety and depression, and vascular alterations. This review explains (a) the possible pathways by which coronavirus-19 can induce the different neurological manifestations, (b) the strategies used by the virus to cross the barrier system, (c) how the immune system responds to the infection, and (d) the treatment than can be administered to the COVID-19 patients.

Venous thromboembolism and COVID-19: a single center experience from an academic tertiary referral hospital of Northern Italy

Preliminary evidence supports the notion that COVID-19 patients may have an increased susceptibility to develop venous thromboembolism (VTE). However, the magnitude of this association still needs to be defined. Furthermore, clinical predictors of thrombogenesis, and the relationship with the inflammatory status are currently unknown. On this basis, we conducted a retrospective, observational study on 259 consecutive COVID-19 patients admitted to an academic tertiary referral hospital in Northern Italy between March 19th and April 6th, 2020. Records of COVID-19 patients with a definite VTE event were reviewed for demographic information, co-morbidities, risk factors for VTE, laboratory tests, and anticoagulation treatment. Twenty-five cases among 259 COVID-19 patients developed VTE (9.6%), all of them having a Padua score > 4, although being under standard anticoagulation prophylaxis since hospital admission. In the VTE subcohort, we found a significant positive correlation between platelet count (PLT) and either C reactive protein (CRP) (p < 0.0001) or lactate dehydrogenase (LDH) (p = 0.0013), while a significant inverse correlation was observed between PLT and mean platelet volume (p < 0.0001). Platelet-to-lymphocyte ratio significantly correlated with CRP (p < 0.0001). The majority of VTE patients was male and younger compared to non-VTE patients (p = 0.002 and p = 0.005, respectively). No significant difference was found in D-dimer levels between VTE and non VTE patients, while significantly higher levels of LDH (p = 0.04) and IL-6 (p = 0.04) were observed in VTE patients in comparison to non-VTE patients. In conclusion, our findings showed a quite high prevalence of VTE in COVID-19 patients. Raised inflammatory indexes and increased serum levels of pro-inflammatory cytokines should raise the clinical suspicion of VTE.

A thrombin-PAR1/2 feedback loop amplifies thromboinflammatory endothelial responses to the viral RNA analogue poly(I:C)

Activation of blood coagulation and endothelial inflammation are hallmarks of respiratory infections with RNA viruses that contribute significantly to the morbidity and mortality of patients with severe disease. We investigated how signaling by coagulation proteases affects the quality and extent of the response to the TLR3-ligand poly(I:C) in human endothelial cells. Genome-wide RNA profiling documented additive and synergistic effects of thrombin and poly(I:C) on the expression level of many genes. The most significantly active genes exhibiting synergistic induction by costimulation with thrombin and poly(I:C) included the key mediators of 2 critical biological mechanisms known to promote endothelial thromboinflammatory functions: the initiation of blood coagulation by tissue factor and the control of leukocyte trafficking by the endothelial-leukocyte adhesion receptors E-selectin (gene symbol, SELE) and VCAM1, and the cytokines and chemokines CXCL8, IL-6, CXCL2, and CCL20. Mechanistic studies have indicated that synergistic costimulation with thrombin and poly(I:C) requires proteolytic activation of protease-activated receptor 1 (PAR1) by thrombin and transactivation of PAR2 by the PAR1-tethered ligand. Accordingly, a small-molecule PAR2 inhibitor suppressed poly(I:C)/thrombin-induced leukocyte-endothelial adhesion, cytokine production, and endothelial tissue factor expression. In summary, this study describes a positive feedback mechanism by which thrombin sustains and amplifies the prothrombotic and proinflammatory function of endothelial cells exposed to the viral RNA analogue, poly(I:C) via activation of PAR1/2.

Drug repurposing against SARS-CoV-2 receptor binding domain using ensemble-based virtual screening and molecular dynamics simulations

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused worldwide pandemic and is responsible for millions of worldwide deaths due to -a respiratory disease known as COVID-19. In the search for a cure of COVID-19, drug repurposing is a fast and cost-effective approach to identify anti-COVID-19 drugs from existing drugs. The receptor binding domain (RBD) of the SARS-CoV-2 spike protein has been a main target for drug designs to block spike protein binding to ACE2 proteins. In this study, we probed the conformational plasticity of the RBD using long molecular dynamics (MD) simulations, from which, representative conformations were identified using clustering analysis. Three simulated conformations and the original crystal structure were used to screen FDA approved drugs (2466 drugs) against the predicted binding site at the ACE2-RBD interface, leading to 18 drugs with top docking scores. Notably, 16 out of the 18 drugs were obtained from the simulated conformations, while the crystal structure suggests poor binding. The binding stability of the 18 drugs were further investigated using MD simulations. Encouragingly, 6 drugs exhibited stable binding with RBD at the ACE2-RBD interface and 3 of them (gonadorelin, fondaparinux and atorvastatin) showed significantly enhanced binding after the MD simulations. Our study shows that flexibility modeling of SARS-CoV-2 RBD using MD simulation is of great help in identifying novel agents which might block the interaction between human ACE2 and the SARS-CoV-2 RBD for inhibiting the virus infection.

Practical Recommendations for the Management of Patients with ITP During the COVID-19 Pandemic

The current COVID-19 pandemic requires revisiting our current approach to major blood disorders, including ITP (Immune Thrombocytopenia), stirring up the production of several disease-specific practical guidelines. This report describes an updated version of consensus-based practical guidelines on the management of ITP, adapted to the Italian health system and social context. It highlights the role of the hematologist in offering guidance for choosing differentiated approaches in relation to specific circumstances and is intended to provide them with a useful tool for sharing the decision-making process with their patients.

Probably, the greatest risk to avoid for a patient with suspected, ongoing or relapsed ITP - that is not severe enough to place him or her at risk for major bleeding - is to be infected in non-hospital and hospital healthcare settings. This risk must be carefully considered when adapting the diagnostic and therapeutic approach.

More in detail, the document first addresses the appropriate management for COVID-19 negative patients with newly diagnosed ITP or who experience a relapse of previous ITP, according to first and second lines of treatment and then the management of COVID-19 positive patients according to their severity, from paucisymptomatic to those requiring admission to Intensive Cure Units (ICU). The pros and cons of the different treatments required to correct platelet count are discussed, as are some specific situations, including chronic ITP, splenectomy, thromboembolic complication and anti COVID-19 vaccination.

Diagnostic Delay of Pulmonary Embolism in COVID-19 Patients

Pulmonary embolism (PE) is a frequent, life-threatening COVID-19 complication, whose diagnosis can be challenging because of its non-specific symptoms. There are no studies assessing the impact of diagnostic delay on COVID-19 related PE. The aim of our exploratory study was to assess the diagnostic delay of PE in COVID-19 patients, and to identify potential associations between patient- or physician-related variables and the delay. This is a single-center observational retrospective study that included 29 consecutive COVID-19 patients admitted to the San Matteo Hospital Foundation between February and May 2020, with a diagnosis of PE, and a control population of 23 non-COVID-19 patients admitted at our hospital during the same time lapse in 2019. We calculated the patient-related delay (i.e., the time between the onset of the symptoms and the first medical examination), and the physician-related delay (i.e., the time between the first medical examination and the diagnosis of PE). The overall diagnostic delay significantly correlated with the physician-related delay (p < 0.0001), with the tendency to a worse outcome in long physician-related diagnostic delay (p = 0.04). The delay was related to the presence of fever, respiratory symptoms and high levels of lactate dehydrogenase. It is important to rule out PE as soon as possible, in order to start the right therapy, to improve patient's outcome and to shorten the hospitalization.

The Potency of Seaweed Sulfated Polysaccharides for the Correction of Hemostasis Disorders in COVID-19

Hemostasis disorders play an important role in the pathogenesis, clinical manifestations, and outcome of COVID-19. First of all, the hemostasis system suffers due to a complicated and severe course of COVID-19. A significant number of COVID-19 patients develop signs of hypercoagulability, thrombocytopenia, and hyperfibrinolysis. Patients with severe COVID-19 have a tendency toward thrombotic complications in the venous and arterial systems, which is the leading cause of death in this disease. Despite the success achieved in the treatment of SARS-CoV-2, the search for new effective anticoagulants, thrombolytics, and fibrinolytics, as well as their optimal dose strategies, continues to be relevant. The wide therapeutic potential of seaweed sulfated polysaccharides (PSs), including anticoagulant, thrombolytic, and fibrinolytic activities, opens up new possibilities for their study in experimental and clinical trials. These natural compounds can be important complementary drugs for the recovery from hemostasis disorders due to their natural origin, safety, and low cost compared to synthetic drugs. In this review, the authors analyze possible pathophysiological mechanisms involved in the hemostasis disorders observed in the pathological progression of COVID-19, and also focus the attention of researchers on seaweed PSs as potential drugs aimed to correction these disorders in COVID-19 patients. Modern literature data on the anticoagulant, antithrombotic, and fibrinolytic activities of seaweed PSs are presented, depending on their structural features (content and position of sulfate groups on the main chain of PSs, molecular weight, monosaccharide composition and type of glycosidic bonds, the degree of PS chain branching, etc.). The mechanisms of PS action on the hemostasis system and the issues of oral bioavailability of PSs, important for their clinical use as oral anticoagulant and antithrombotic agents, are considered. The combination of the anticoagulant, thrombolytic, and fibrinolytic properties, along with low toxicity and relative cheapness of production, open up prospects for the clinical use of PSs as alternative sources of new anticoagulant and antithrombotic compounds. However, further investigation and clinical trials are needed to confirm their efficacy.

Use of low-molecular weight heparin, transfusion and mortality in COVID-19 patients not requiring ventilation

It is still debated whether prophylactic doses of low-molecular- weight heparin (LMWH) are always effective in preventing Venous Thromboembolism (VTE) and mortality in COVID-19. Furthermore, there is paucity of data for those patients not requiring ventilation. We explored mortality and the safety/efficacy profile of LMWH in a cohort of Italian patients with COVID-19 who did not undergo ventilation. From the initial cohort of 422 patients, 264 were enrolled. Most (n = 156, 87.7%) received standard LMWH prophylaxis during hospitalization, with no significant difference between medical wards and Intensive Care Unit (ICU). Major or not major but clinically relevant hemorrhages were recorded in 13 (4.9%) patients: twelve in those taking prophylactic LMWH and one in a patient taking oral anticoagulants (p: n.s.). Thirty-nine patients (14.8%) with median age 75 years. were transfused. Hemoglobin (Hb) at admission was significantly lower in transfused patients and Hb at admission inversely correlated with the number of red blood cells units transfused (p < 0.001). In-hospital mortality occurred in 76 (28.8%) patients, 46 (24.3%) of whom admitted to medical wards. Furthermore, Hb levels at admittance were significantly lower in fatalities (g/dl 12.3; IQR 2.4 vs. 13.3; IQR 2.8; Mann–Whitney U-test; p = 0.001). After the exclusion of patients treated by LMWH intermediate or therapeutic doses (n = 32), the logistic regression showed that prophylaxis significantly and independently reduced mortality (OR 0.31, 95% CI 0.13–0.85). Present data show that COVID-19 patients who do not require ventilation benefit from prophylactic doses of LMWH.

Mechanisms of thrombosis and cardiovascular complications in COVID-19

BACKGROUND

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

METHODS

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

RESULTS AND CONCLUSIONS

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

Endothelialitis plays a central role in the pathophysiology of severe COVID-19 and its cardiovascular complications

This clinical review paper discusses the pathophysiology of the pulmonary and cardiovascular manifestations of a SARS-CoV-2 infection and the ensuing implications on acute cardiovascular care in patients presenting with a severe COVID-19 syndrome admitted to an intensive acute cardiac care unit. The high prevalence of old age, obesity, diabetes, hypertension, heart failure, and ischaemic heart disease in patients who develop a severe to critical COVID-19 syndrome suggests shared pathophysiological mechanisms. Pre-existing endothelial dysfunction and an impaired innate immune response promote the development by the viral infection of an acute endothelialitis in the pulmonary microcirculation complicated by abnormal vasoconstrictor responses, luminal plugging by inflammatory cells, and intravascular thrombosis. This endothelialitis extends into the systemic circulation what may lead to acute myocardial injury, myocarditis, and thromboembolic complications both in the arterial and venous circulation.

Vascular Abnormalities Detected with Chest CT in COVID-19: Spectrum, Association with Parenchymal Lesions, Cardiac Changes, and Correlation with Clinical Severity (COVID-CAVA Study)

Although vascular abnormalities are thought to affect coronavirus disease 2019 (COVID-19) patients’ outcomes, they have not been thoroughly characterized in large series of unselected patients. The Swiss national registry coronavirus-associated vascular abnormalities (CAVA) is a multicentric cohort of patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection who underwent a clinically indicated chest computed tomography (CT) aiming to assess the prevalence, severity, distribution, and prognostic value of vascular and non-vascular-related CT findings. Clinical outcomes, stratified as outpatient treatment, inpatient without mechanical ventilation, inpatient with mechanical ventilation, or death, will be correlated with CT and biological markers. The main objective is to assess the prevalence of cardiovascular abnormalities–including pulmonary embolism (PE), cardiac morphology, and vascular congestion. Secondary objectives include the predictive value of cardiovascular abnormalities in terms of disease severity and fatal outcome and the association of lung inflammation with vascular abnormalities at the segmental level. New quantitative approaches derived from CT imaging are developed and evaluated in this study. Patients with and without vascular abnormalities will be compared, which is supposed to provide insights into the prognostic role and potential impact of such signs on treatment strategy. Results are expected to enable the development of an integrative score combining both clinical data and imaging findings to predict outcomes.

Acute Coronary Syndrome and Arrhytmia Induced by SARS-CoV-2 Infection in a Patient with Non-Significant LAD Lesion. A Case Report

Background: Coronavirus disease 2019 (COVID-19) has emerged as a pandemic and public health crisis of an unprecedent effect. Clinical studies reported an association between COVID-19 and cardiovascular disease, whereas COVID-19 itself can induce myocardial injury, arrhythmia, acute coronary syndrome, and venous thromboembolism.

Case summary: A patient diagnosed via screening coronary computed tomography angiography with non-obstructive coronary artery disease was hospitalized with non-ST elevation myocardial infarction and atrial flutter during a severe respiratory infection episode with SARS-CoV-2. After recovery from the infectious episode, fractional flow reserve-guided elective percutaneous coronary intervention with drug-eluting stent was performed.

Conclusions: COVID-19 intercurrence in a cardiovascular patient with nonobstructive coronary artery disease triggered coronary plaque vulnerabilization with subsequent development of an acute coronary syndrome. SARS-CoV-2 proved to be involved via direct viral tissue involvement and concomitant mechanisms derived from systemic illness in the development of a severe supraventricular arrhythmic event.

Role of biomaterials in the diagnosis, prevention, treatment, and study of corona virus disease 2019 (COVID-19)

Recently emerged novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the resulting corona virus disease 2019 (COVID-19) led to urgent search for methods to prevent and treat COVID-19. Among important disciplines that were mobilized is the biomaterials science and engineering. Biomaterials offer a range of possibilities to develop disease models, protective, diagnostic, therapeutic, monitoring measures, and vaccines. Among the most important contributions made so far from this field are tissue engineering, organoids, and organ-on-a-chip systems, which have been the important frontiers in developing tissue models for viral infection studies. Also, due to low bioavailability and limited circulation time of conventional antiviral drugs, controlled and targeted drug delivery could be applied alternatively. Fortunately, at the time of writing this paper, we have two successful vaccines and new at-home detection platforms. In this paper, we aim to review recent advances of biomaterial-based platforms for protection, diagnosis, vaccination, therapeutics, and monitoring of SARS-CoV-2 and discuss challenges and possible future research directions in this field.

Differential diagnoses of COVID-19 pneumonia: the current challenge for the radiologist-a pictorial essay

BACKGROUND

COVID-19 pneumonia represents the most severe pandemic of the twenty-first century and has crucial clinical, social and economical implications. The scientific community has focused attention and resources on clinical and radiological features of COVID-19 pneumonia. Few papers analysing the vast spectrum of differential diagnoses have been published.

MAIN BODY

Complexity of differential diagnosis lays in the evidence of similar radiological findings as ground-glass opacities, crazy paving pattern and consolidations in COVID-19 pneumonia and a multitude of other lung diseases. Differential diagnosis is and will be extremely important during and after the pandemic peak, when there are fewer COVID-19 pneumonia cases. The aim of our pictorial essay is to schematically present COVID-19 pneumonia most frequent differential diagnoses to help the radiologist face the current COVID-19 pneumonia challenge.

CONCLUSIONS

Clinical data, laboratory tests and imaging are pillars of a trident, which allows to reach a correct diagnosis in order to grant an excellent allocation of human and economical resources. The radiologist has a pivotal role in the early diagnosis of COVID-19 pneumonia because he may raise suspicion of the pathology and help to avoid COVID-19 virus spread.

Incidence of venous thromboembolism among patients with severe COVID-19 requiring mechanical ventilation compared to other causes of respiratory failure: a prospective cohort study

Previous studies have suggested that COVID-19 pneumonia is associated with an increased risk of venous thromboembolism (VTE). This study aimed to investigate the incidence of VTE among mechanically ventilated adults with COVID-19 pneumonia, compared to patients with respiratory failure related to other causes. Prospective study that enrolled critically ill adults with suspected COVID-19 pneumonia between June 2, 2020 and August 11, 2020. Critically ill adults with suspected COVID-19 pneumonia who required mechanical ventilation within 24 h after hospital admission were followed until death or hospital discharge. Sequential ultrasonography screening of the lower extremities and catheter insertion sites, as well as testing for plasma biochemical markers, were performed at the intensive care unit admission, day 3, day 7, and day 14. The primary outcome was a composite of deep venous thrombosis, pulmonary embolism, and thrombosis at the central catheter insertion sites. We enrolled 70 patients, including 57 patients with COVID-19 and 13 patients without COVID-19, and all patients completed follow-up. The incidence of the primary outcome was higher among patients with COVID-19 than among patients with respiratory failure related to other etiologies (36.8% vs. 0%, p = 0.023). Multivariate regression analysis revealed that VTE was independently associated with a COVID-19 diagnosis (odds ratio: 6.28, 95% confidence interval: 1.19–68.07) and D-dimer concentration (1-ng/mL increase, odds ratio: 1.15, 95% confidence interval: 1.05–1.30). The incidence of VTE was higher among critically ill mechanically ventilated patients, relative to among patients with respiratory failure related to other causes.

Edoxaban, a direct oral factor Xa inhibitor, ameliorates coagulation, microvascular thrombus formation, and acute liver injury in a lipopolysaccharide-induced coagulopathy model in rats

Infection increases the risk of thrombosis through the activation of inflammation and coagulation. Edoxaban, a direct oral factor Xa inhibitor, is used for the prevention and treatment of thrombotic diseases. The aim of this study was to determine the effects of edoxaban on microvascular thrombus formation in a rat model of lipopolysaccharide (LPS)-induced coagulopathy. Rats were intravenously injected with 7.5 mg/kg of LPS (Escherichia coli 055:B5). Immediately after LPS injection, the rats were treated with subcutaneous injection of edoxaban. At 2 and 6 h after the injection of LPS, biomarkers of coagulation and organ damages and inflammatory cytokines were measured. Microvascular thrombus formation in organs was evaluated using ¹²⁵I-fibrinogen (human) or by the pathological analysis. Mortality was examined 24 h after LPS injection. After the injection of LPS, D-dimer and thrombin-antithrombin complex increased and platelet numbers decreased, indicating the activation of coagulation. Microvascular thrombi were found in the liver. Markers of liver injury (aspartate aminotransferase and alanine aminotransferase) also increased. Treatment with edoxaban attenuated the changes in the coagulation markers and microvascular thrombus formation in the liver. Edoxaban suppressed the increase in the liver injury markers and reduced the mortality. Edoxaban did not affect the levels of inflammatory cytokines. In conclusions, edoxaban significantly inhibited the activation of coagulation, the formation of microvascular thrombus in the liver and the liver damage, and reduced mortality in rats injected with LPS. These results suggest that the FXa inhibition by edoxaban might be a beneficial therapy for the management of infection-associated thrombosis.

Complement activation and coagulopathy - an ominous duo in COVID19

INTRODUCTION

COVID-19 has similarities to the Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) outbreaks, as severe patients and non-survivors have frequently shown abnormal coagulation profiles. Immune-mediated pathology is a key player in this disease; hence, the role of the complement system needs assessment. The complement system and the coagulation cascade share an intricate network, where multiple mediators maintain a balance between both pathways. Coagulopathy in COVID-19, showing mixed features of complement-mediated and consumption coagulopathy, creates a dilemma in diagnosis and management.

AREAS COVERED

Pathophysiology of coagulopathy in COVID-19 patients, with a particular focus on D-dimer and its role in predicting the severity of COVID-19 has been discussed. A comprehensive search of the medical literature on PubMed was done till May 30th, 2020 with the keywords 'COVID-19', 'SARS-CoV-2', 'Coronavirus', 'Coagulopathy', and 'D-dimer'. Twenty-two studies were taken for weighted pooled analysis of D-dimer.

EXPERT OPINION

A tailored anticoagulant regimen, including intensification of standard prophylactic regimens with low-molecular-weight heparin is advisable for COVID-19 patients. Atypical manifestations and varying D-dimer levels seen in different populations bring forth the futility of uniform recommendations for anticoagulant therapy. Further, direct thrombin inhibitors and platelet inhibitors in a patient-specific manner should also be considered.

Pulmonary thromboembolism in coronavirus disease 2019 patients undergoing thromboprophylaxis

We aimed to investigate the prevalence of pulmonary thromboembolism (PTE) and its association with clinical variables in a cohort of hospitalized coronavirus disease 2019 (COVID-19) patients receiving low-molecular-weight heparin (LMWH) at prophylactic dosage.In this retrospective observational study we included COVID-19 patients receiving prophylactic LMWH from admission but still referred for lower-limbs venous Doppler ultrasound (LL-US) and computed tomography pulmonary angiography (CTPA) for clinical PTE suspicion. A dedicated radiologist reviewed CTPA images to assess PTE presence/extension.From March 1 to April 30, 2020, 45 patients were included (34 men, median age 67 years, interquartile range [IQR] 60-76). Twenty-seven (60%) had PTE signs at CTPA, 17/27 (63%) with bilateral involvement, none with main branch PTE. In 33/45 patients (73%) patients LL-US was performed before CTPA, with 3 patients having superficial vein thrombosis (9%, none with CTPA-confirmed PTE) and 1 patient having deep vein thrombosis (3%, with CTPA-confirmed PTE). Thirty-three patients (73%) had at least one comorbidity, mainly hypertension (23/45, 51%) and cardiovascular disease (15/45, 33%). Before CTPA, 5 patients had high D-dimer (11.21 μg/mL, IQR 9.10-13.02), 19 high fibrinogen (550 mg/dL, IQR 476-590), 26 high interleukin-6 (79 pg/mL, IQR 31-282), and 11 high C-reactive protein (9.60 mg/dL, IQR 6.75-10.65), C-reactive protein being the only laboratory parameter significantly differing between patients with and without PTE (P = .002)High PTE incidence (60%) in COVID-19 hospitalized patients under prophylactic LMWH could substantiate further tailoring of anticoagulation therapy.

Heparin in COVID-19 Patients Is Associated with Reduced In-Hospital Mortality: The Multicenter Italian CORIST Study

INTRODUCTION

 A hypercoagulable condition was described in patients with coronavirus disease 2019 (COVID-19) and proposed as a possible pathogenic mechanism contributing to disease progression and lethality.

AIM

 We evaluated if in-hospital administration of heparin improved survival in a large cohort of Italian COVID-19 patients.

METHODS

 In a retrospective observational study, 2,574 unselected patients hospitalized in 30 clinical centers in Italy from February 19, 2020 to June 5, 2020 with laboratory-confirmed severe acute respiratory syndrome coronavirus-2 infection were analyzed. The primary endpoint in a time-to event analysis was in-hospital death, comparing patients who received heparin (low-molecular-weight heparin [LMWH] or unfractionated heparin [UFH]) with patients who did not. We used multivariable Cox proportional-hazards regression models with inverse probability for treatment weighting by propensity scores.

RESULTS

 Out of 2,574 COVID-19 patients, 70.1% received heparin. LMWH was largely the most used formulation (99.5%). Death rates for patients receiving heparin or not were 7.4 and 14.0 per 1,000 person-days, respectively. After adjustment for propensity scores, we found a 40% lower risk of death in patients receiving heparin (hazard ratio = 0.60; 95% confidence interval: 0.49-0.74; E-value = 2.04). This association was particularly evident in patients with a higher severity of disease or strong coagulation activation.

CONCLUSION

 In-hospital heparin treatment was associated with a lower mortality, particularly in severely ill COVID-19 patients and in those with strong coagulation activation. The results from randomized clinical trials are eagerly awaited to provide clear-cut recommendations.

COVID-19 and Obesity: Overlapping of Two Pandemics

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic has recently led to worldwide research efforts to identify subjects at greater risk of developing more severe illness: overall obesity displayed a strong correlation with critical illness and major severity of COVID-19 manifestations.

SUMMARY

Obesity and metabolic disorders are closely linked to chronic systemic inflammation. The adipose tissue constitutes a source of cytokines, which configure a low-grade inflammation and a hypercoagulation status; in addition, diagnosis and care of obese patients are often complicated by excess weight and ventilation difficulties. Key Messages: This review aims to examine the intersection between obesity and adverse outcomes of COVID-19, in order to investigate its preventive and/or therapeutic potential in the management of obesity-related COVID-19 complications.

Review: Obesity and COVID-19: A Detrimental Intersection

Obesity has been recognized as an independent risk factor for critical illness and major severity in subjects with coronavirus disease 2019 (COVID-19). The role of fat distribution, particularly visceral fat (often linked to metabolic abnormalities), is still unclear. The adipose tissue represents a direct source of cytokines responsible for the pathological modifications occurring within adipose tissue in obese subjects. Adipokines are a crucial connection between metabolism and immune system: their dysregulation in obesity contributes to chronic low-grade systemic inflammation and metabolic comorbidities. Therefore the increased amount of visceral fat can lead to a proinflammatory phenotypic shift. This review analyzes the interrelation between obesity and COVID-19 severity, as well as the cellular key players and molecular mechanisms implicated in adipose inflammation, investigating if adipose tissue can constitute a reservoir for viral spread, and contribute to immune activation and cytokines storm. Targeting the underlying molecular mechanisms might have therapeutic potential in the management of obesity-related complications in COVID-19 patients.

Blood test dynamics in hospitalized COVID-19 patients: Potential utility of D-dimer for pulmonary embolism diagnosis

BACKGROUND

A higher incidence of thrombotic events, mainly pulmonary embolism (PE), has been reported in hospitalized patients with COVID-19. The main objective was to assess clinical and laboratory differences in hospitalized COVID-19 patients according to occurrence of PE.

METHODS

This retrospective study included all consecutive patients hospitalized with COVID-19 who underwent a computed tomography (CT) angiography for PE clinical suspicion. Clinical data and median blood test results distributed into weekly periods from COVID-19 symptoms onset, were compared between PE and non-PE patients.

RESULTS

Ninety-two patients were included, 29 (32%) had PE. PE patients were younger (63.9 (SD 13.7) vs 69.9 (SD 12.5) years). Clinical symptoms and COVID-19 CT features were similar in both groups. PE was diagnosed after a mean of 20.0 (SD 8.6) days from the onset of COVID-19 symptoms. Corticosteroid boluses were more frequently used in PE patients (62% vs. 43%). No patients met ISTH DIC criteria. Any parameter was statistically significant or clinically relevant except for D-Dimer when comparing both groups. Median values [IQR] of D-dimer in PE vs non-PE patients were: week 2 (2010.7 [770.1-11208.9] vs 626.0 [374.0-2382.2]; p = 0.004); week 3 (3893.1 [1388.2-6694.0] vs 1184.4 [461.8-2447.8]; p = 0.003); and week 4 (2736.3 [1202.1-8514.1] vs 1129.1 [542.5-2834.6]; p = 0.01). Median fold-increase of D-dimer between week 1 and 2 differed between groups (6.64 [3.02-23.05] vs 1.57 [0.64-2.71], p = 0.003); ROC curve AUC was 0.879 (p = 0.003) with a sensitivity and specificity for PE of 86% and 80%, respectively.

CONCLUSIONS

Among hospitalized COVID-19 patients, D-dimer levels are higher at weeks 2, 3 and 4 after COVID-19 symptom onset in patients who develop PE. This difference is more pronounced when the fold increase between weeks 1 and 2 is compared.

A comprehensive review on sarilumab in COVID-19

Introduction: The coronavirus disease 2019 (COVID-19) pandemic, caused by a newly discovered coronavirus (severe acute respiratory syndrome coronavirus 2, or SARS-CoV-2), continues to spread all around the world. Despite the emergency of COVID-19 worldwide, remdesivir is the only treatment that has been recently approved to treat the diseases, and other effective therapies are still lacking. SARS-CoV-2 may cause severe illness in 20% of patients. Based on available data, there is an association between interleukin-6 (IL-6) and severe COVID-19. Sarilumab is a fully human immunoglobulin G1 monoclonal antibody binding to both membrane-bound and soluble IL-6 receptors with high affinity and has been considered for off-label use in the treatment of COVID-19.Areas covered: The present article reviews recently published literature focusing on the pathophysiology of COVID-19 induced cytokine storm, the potential therapeutic role, and important clinical issues of sarilumab in the treatment of COVID-19 patients.Expert opinion: The off-label treatment administration is unavoidable in the critical situation of the COVID-19 pandemic. Further efforts should be directed to determine mechanisms of SARS-CoV-2 induced immune dysregulation as well as indications of sarilumab in the patients with COVID-19 to minimize concerns regarding its off-label administration.

Atypical Endovascular Cells in SARS-CoV-2 Pneumonia

The autopsy findings for 3 cases of SARS-(CoV-2) pneumonia-related deaths are reported with pulmonary histology and immunohistochemistry findings. In 2 cases (cases 1 and 2), the time interval from presentation to death was approximately 1 week, whereas for case 3, the time interval from presentation to death was hours. Case 1 and case 2 presented with shortness of breath, cough, and flu-like symptoms. The decedent from case 3 died shortly after presenting to a local emergency room with high fever, chest and abdominal pain, and shortness of breath. All 3 cases had 1 or more comorbidities. The postmortem interval for cases 1 and 2 was 2 weeks as they died at sea and were stored on board within the respective cruise ships' refrigeration units, whereas case 3 was examined within 24 hours of death. The autopsies were conducted at the Miami-Dade County Medical Examiners Department under routine infectious precautions. Salient clinical history and autopsy findings are summarized. Microscopic examination revealed pneumonia with associated atypical endovascular cells.

An Evidence-based Protocol for Minimizing Thromboembolic Events in SARS-CoV-2 Infection

Coronavirus Disease 2019 (COVID-19) is complicated by significant coagulopathy, that manifests in the form of both pulmonary artery microthromboses and systemic venous thromboembolism (VTE) leading to excess mortality. Dysregulated innate immune response in the lung due to viral-entry mediated angiotensin-I-converting enzyme 2 (ACE2) receptor downregulation causes endothelial injury in the pulmonary vasculature, inflammatory cytokine release, increased thrombin generation and impaired fibrinolysis. The inflammatory disease process, immobilization with prolonged hospital stay, hypoxia due to extensive lung injury and pre-existing comorbidities can contribute to thromboembolic episodes (TE). The observed risk for TE in COVID-19 is high despite anticoagulation, particularly in intensive care unit (ICU) patients. A high level of clinical suspicion, lower threshold for diagnostic imaging and aggressive early and extended thromboprophylaxis is indicated. The available evidence on the optimal strategies to prevent, diagnose, and treat VTE in patients with COVID-19 is heterogenous, but rapidly evolving. We propose an evidence-based, risk-stratified protocol in approaching the risk of TE episodes in COVID-19 patients.

Coagulopathy, Venous Thromboembolism, and Anticoagulation in Patients with COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has led to a worldwide pandemic, and patients with the infection are referred to as having COVID‐19. Although COVID‐19 is commonly considered a respiratory disease, there is clearly a thrombotic potential that was not expected. The pathophysiology of the disease and subsequent coagulopathy produce an inflammatory, hypercoagulable, and hypofibrinolytic state. Several observational studies have demonstrated surprisingly high rates of venous thromboembolism (VTE) in both general ward and intensive care patients with COVID‐19. Many of these observational studies demonstrate high rates of VTE despite patients being on standard, or even higher intensity, pharmacologic VTE prophylaxis. Fibrinolytic therapy has also been used in patients with acute respiratory distress syndrome. Unfortunately, high quality randomized controlled trials are lacking. A literature search was performed to provide the most up‐to‐date information on the pathophysiology, coagulopathy, risk of VTE, and prevention and treatment of VTE in patients with COVID‐19. These topics are reviewed in detail, along with practical issues of anticoagulant selection and duration. Although many international organizations have produced guidelines or consensus statements, they do not all cover the same issues regarding anticoagulant therapy for patients with COVID‐19, and they do not all agree. These statements and the most recent literature are combined into a list of clinical considerations that clinicians can use for the prevention and treatment of VTE in patients with COVID‐19.

COVID-19, coagulopathy and venous thromboembolism: more questions than answers

The acute respiratory illnesses caused by severe acquired respiratory syndrome corona Virus-2 (SARS-CoV-2) is a global health emergency, involving more than 8.6 million people worldwide with more than 450,000 deaths. Among the clinical manifestations of COVID-19, the disease that results from SARS-CoV-2 infection in humans, a prominent feature is a pro-thrombotic derangement of the hemostatic system, possibly representing a peculiar clinicopathologic manifestation of viral sepsis. The severity of the derangement of coagulation parameters in COVID-19 patients has been associated with a poor prognosis, and the use of low molecular weight heparin (LMWH) at doses registered for prevention of venous thromboembolism (VTE) has been endorsed by the World Health Organization and by Several Scientific societies. However, some relevant issues on the relationships between COVID-19, coagulopathy and VTE have yet to be fully elucidated. This review is particularly focused on four clinical questions: What is the incidence of VTE in COVID-19 patients? How do we frame the COVID-19 associated coagulopathy? Which role, if any, do antiphospolipid antibodies have? How do we tackle COVID-19 coagulopathy? In the complex scenario of an overwhelming pandemic, most everyday clinical decisions have to be taken without delay, although not yet supported by a sound scientific evidence. This review discusses the most recent findings of basic and clinical research about the COVID-associated coagulopathy, to foster a more thorough knowledge of the mechanisms underlying this compelling disease.

Management of a COVID-19 Patient during ECMO: Paying Attention to Acquired von Willebrand Syndrome

Patients with severe COVID-19 often experience complications including coagulopathy and fatal thrombosis. COVID-19 pneumonia sometimes leads to acute respiratory distress syndrome, requiring extracorporeal membrane oxygenation (ECMO), during which thrombosis and bleeding are major causes of death. Anticoagulation such as heparin is essential for COVID-19 patients on ECMO; however, bleeding might be caused by not only heparin, but also acquired von Willebrand syndrome (AVWS). To date, no study has examined ECMO-related bleeding and AVWS in COVID-19 patients.

We report a COVID-19 patient who experienced bleeding from AVWS in addition to disseminated intravascular coagulation (DIC) during ECMO. The level of high–molecular weight VWF multimers decreased during ECMO therapy, and these findings promptly improved after discontinuation of ECMO. Plasma levels of VWF antigen were extremely high, probably due to endothelial cell damage caused by COVID-19. On the other hand, plasma levels of ADAMTS13 activity were moderately reduced, to 20–30% of normal. The patient was successfully treated with cryoprecipitate in bleeding during ECMO without a reduction in heparin, which might have induced thromboembolism. Bleeding found in this patient might be caused by AVWS and DIC.

Severe COVID-19 patients are in a thrombotic state and need to receive anticoagulant therapy. However, once they receive ECMO therapy, bleeding symptoms could be observed. In such cases, physicians should think of AVWS in addition to the side effect of heparin and DIC.

Coagulation Dysfunction

CONTEXT.—

The coronavirus disease 2019 (COVID-19) is a highly contagious respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Coagulation dysfunction is a hallmark in patients with COVID-19. Fulminant thrombotic complications emerge as critical issues in patients with severe COVID-19.

OBJECTIVE.—

To present a review of the literature and discuss the mechanisms of COVID-19 underlying coagulation activation and the implications for anticoagulant and thrombolytic treatment in the management of COVID-19.

DATA SOURCES.—

We performed a systemic review of scientific papers on the topic of COVID-19, available online via the PubMed NCBI, medRxiv, and Preprints as of May 15, 2020. We also shared our experience on the management of thrombotic events in patients with COVID-19.

CONCLUSIONS.—

COVID-19-associated coagulopathy ranges from mild laboratory alterations to disseminated intravascular coagulation (DIC) with a predominant phenotype of thrombotic/multiple organ failure. Characteristically, high D-dimer levels on admission and/or continuously increasing concentrations of D-dimer are associated with disease progression and poor overall survival. SARS-CoV-2 infection triggers the immune-hemostatic response. Drastic inflammatory responses including, but not limited to, cytokine storm, vasculopathy, and NETosis may contribute to an overwhelming activation of coagulation. Hypercoagulability and systemic thrombotic complications necessitate anticoagulant and thrombolytic interventions, which provide opportunities to prevent or reduce "excessive" thrombin generation while preserving "adaptive" hemostasis and bring additional benefit via their anti-inflammatory effect in the setting of COVID-19.

Emerging patterns of hypercoagulability associated with critical COVID-19: A review

While the COVID-19 pandemic sweeps the world, much evidence is being gathered regarding its novel pathological mechanisms. It is the authors' clinical experience that patients in the intensive care unit suffering from COVID-19 are extremely pro-coagulable, with venous and arterial thromboembolism frequently observed, and losses of vascular access lines and filtration circuits to thrombosis now commonplace. Here, we explore the evidence for hypercoagulability in this group, presenting evidence of both a localised pulmonary hypercoagulability, and a systemic hypercoagulability resulting in thrombosis distant to the pulmonary vasculature. Furthermore, we discuss the possible risk factors exacerbated by, or selected for in COVID-19. We review the available evidence for use of plasma D-dimer as a prognostic marker, exploring the possibility that it acts as a marker of a COVID-19-associated hypercoagulability. We review the evidence for a pro-coagulant subtype of disseminated intravascular coagulation, discussing its clinical significance. Finally, we discuss the current evidence surrounding treatment of COVID-19 hypercoagulability, including prophylactic and treatment-dose heparin, thrombolytic agents, antiplatelet agents, and direct thrombin inhibitors, among others. We suggest areas in which further investigation is urgently needed to reduce the startling incidence of thrombosis in this group, a complication no doubt contributing to morbidity and mortality.

The hypercoagulable state in COVID-19: Incidence, pathophysiology, and management

The 2019 coronavirus disease (COVID-19) presents with a large variety of clinical manifestations ranging from asymptomatic carrier state to severe respiratory distress, multiple organ dysfunction and death. While it was initially considered primarily a respiratory illness, rapidly accumulating data suggests that COVID-19 results in a unique, profoundly prothrombotic milieu leading to both arterial and venous thrombosis. Consistently, elevated D-dimer level has emerged as an independent risk factor for poor outcomes, including death. Several other laboratory markers and blood counts have also been associated with poor prognosis, possibly due to their connection to thrombosis. At present, the pathophysiology underlying the hypercoagulable state is poorly understood. However, a growing body of data suggests that the initial events occur in the lung. A severe inflammatory response, originating in the alveoli, triggers a dysfunctional cascade of inflammatory thrombosis in the pulmonary vasculature, leading to a state of local coagulopathy. This is followed, in patients with more severe disease, by a generalized hypercoagulable state that results in macro- and microvascular thrombosis. Of concern, is the observation that anticoagulation may be inadequate in many circumstances, highlighting the need for alternative or additional therapies. Numerous ongoing studies investigating the pathophysiology of the COVID-19 associated coagulopathy may provide mechanistic insights that can direct appropriate interventional strategies.

One disease, many faces-typical and atypical presentations of SARS-CoV-2 infection-related COVID-19 disease

Since the appearance of the novel coronavirus (severe acute respiratory syndrome-coronavirus-2) and related coronavirus disease 2019 (COVID-19) in China in December 2019, a very high number of small and large patient series have been published in literature from around the world. Even though the classical presentation of COVID-19 is one with respiratory symptoms with or without pneumonia that can be self-limiting or evolve into severe respiratory distress syndrome with multiple organ failure, and secondary bacterial sepsis, a large body of evidence suggests a plethora of other types of clinical presentation. In this exhaustive review, we reviewed all of the published literature on COVID-19 to identify different types of clinical presentations affecting various organ systems, to provide an in-depth analysis that may prove useful for clinicians and health-workers on the frontline, battling the severe pandemic.