The unique characteristics of COVID-19 coagulopathy

An Update on the Status of Vaccine Development for SARS-CoV-2 Including Variants. Practical Considerations for COVID-19 Special Populations

The progress in the development of various vaccine platforms against SARS-CoV-2 have been rather remarkable owing to advancement in molecular and biologic sciences. Most of the current vaccines and those in development focus on targeting the viral spike proteins by generating antibodies of varying spectrum. These vaccines represent a variety of platforms including whole virus vaccines, viral vector vaccines, nucleic acid vaccines representing RNA, DNA, and their hybrid forms.The therapeutic efficacy of these vaccines varies owing to their pharmacodynamic individualities. COVID-19 variants are capable of inducing different pathologic responses and some of which may be resistant to antibodies generated by current vaccines. The current clinical use of these vaccines has been through emergency use authorization until recently. Moreover, the efficacy and safety of these vaccines have been tested in substantial numbers of individuals but studies in special populations that better reflect the global population are pending results. These specialized populations include young children, immunocompromised patients, pregnant individuals, and other specialized groups. Combination approaches, molecularly modified vaccination approaches, and vaccines conferring longer periods of immunity are being currently being investigated, as well as pharmacovigilance studies.The continual transformation of SARS-CoV-2 and its variants are of concern along with the breakthrough infections. These considerations pose new challenges for the development of vaccination platforms. For this purpose, booster doses, combination vaccine approaches, and other modalities are being discussed. This review provides an updated account of currently available vaccines and those in advanced development with reference to their composition and mechanisms of action.A discussion on the use of vaccines in special populations including immunocompromised patients, pregnant women and other specialized populations are also included.

Cytokine Storm and Neuropathological Alterations in Patients with Neurological Manifestations of COVID-19

The COVID-19 pandemic is caused by the severe acute respiratory syndrome coronavirus (SARS-CoV-2), a respiratory pathogen with neuroinvasive potential. Neurological COVID-19 manifestations include loss of smell and taste, headache, dizziness, stroke, and potentially fatal encephalitis. Several studies found elevated proinflammatory cytokines, such as TNF-α, IFN-γ, IL-6 IL-8, IL- 10 IL-16, IL-17A, and IL-18 in severely and critically ill COVID-19 patients may persist even after apparent recovery from infection. Biomarker studies on CSF and plasma and serum from COVID-19 patients have also shown a high level of IL-6, intrathecal IgG, neurofilament light chain (NFL), glial fibrillary acidic protein (GFAP), and tau protein. Emerging evidence on the matter has established the concept of COVID-19-associated neuroinflammation, in the context of COVID-19-associated cytokine storm. While the short-term implications of this condition are extensively documented, its longterm implications are yet to be understood. The association of the aforementioned cytokines with the pathogenesis of neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis, may increase COVID-19 patients' risk of developing neurodegenerative diseases. Analysis of proinflammatory cytokines and CSF biomarkers in patients with COVID-19 can contribute to the early detection of the disease's exacerbation, monitoring the neurological implications of the disease and devising risk scales, and identifying treatment targets.

Assessment of Healthcare Resource Utilization by Anticoagulant Heparinoid Dosage Level in Patients Hospitalized with COVID-19

The aim was to describe inpatients with COVID-19 empirically prescribed heparinoid anticoagulants and compare resource utilization between prophylactic/low-dose and therapeutic/high-dose groups. Methods: This retrospective observational study used real-world data from 880 US hospitals in the PINC AI™ Healthcare Database during 4/1/2020–11/30/2020. Descriptive analysis was used to characterize patients. Multivariable regression was used to evaluate intensive care unit (ICU) admissions, length of stay (LOS), mortality, and costs by anticoagulation dose group, adjusting for cohort characteristics. Among 122,508 inpatients, 29,225 (23.9%) received therapeutic/high-dose, and 93,283 (76.1%) received prophylactic/low-dose anticoagulation. The high-dose group had more comorbidities and worse laboratory values compared with low-dose. Respectively, ICU admission rates were 36.7% and 19.1% and LOS median (Q1, Q3) was 8 (5, 15) and 5 (3, 9) days. In separate adjusted models, high-dose anticoagulation was associated with a 45% increase in odds of ICU admission, 26% increase in odds of in-hospital mortality, 21% longer average LOS, and 28% greater average total cost compared with low-dose (each P < 0.001). Prophylactic/low-dose anticoagulation treatment was associated with decreased healthcare resource utilization (HRU) in hospitalized patients with COVID-19.

Association of systemic complications with mortality in coronavirus disease of 2019: A cohort study on intensive care unit patients

Background:

Since the beginning of the coronavirus disease of 2019 (COVID-19) pandemic, concerns raised by the growing number of deaths worldwide. Acute respiratory distress syndrome (ARDS) and extrapulmonary complications can correlate with prognosis in COVID-19 patients. This study evaluated the association of systemic complications with mortality in severely affected COVID-19 patients.

Materials and Methods:

This retrospective study was done on 51 intensive care unit (ICU)-admitted COVID-19 adult patients who were admitted to the ICU ward of Khorshid hospital, affiliated with Isfahan University of Medical Sciences. Only the patients who had a definite hospitalization outcome (dead vs. survivors) were included in the study. Daily clinical and paraclinical records were used to diagnose in-hospital complications in these patients.

Results:

The sample was comprised of 37 males (72.5%) and 14 females (27.4%). The median age of patients was 63 years (Min: 20, Max: 84), with the mortality rate of 47.1%. In total, 70.6% of patients had at least one coexisting disorder. Chronic kidney disease was associated with the worse outcome (29.16% of dead patients against 3.70 of survived ones). Mechanical ventilation was used in 58.8% of patients. Patients who had received invasive ventilation were more likely to die (87.50% of dead patients against 7.40 of survivors), Complications including sepsis and secondary infections (odds ratio: 8.05, confidence interval: 2.11–30.63) was the strongest predictors of mortality.

Conclusion:

Complications including sepsis and secondary infections can increase the risk of death in ICU-admitted COVID-19 patients. Therefore, it is substantial that the physicians consider preventing or controlling these complications.

Insights into Fibrinogen-Mediated COVID-19 Hypercoagubility in Critically Ill Patients

Coronavirus disease-2019 (COVID-19) is associated with hypercoagulability that may cause thromobembolic complications. We describe our recent studies investigating the mechanisms of hypercoagulability in patients with severe COVID-19 requiring mechanical ventilation during the COVID-19 crisis in New York City in spring 2020. Using rotational thombelastometry we found that almost all patients with severe COVID-19 had signs of hypercoagulability compared with non-COVID-19 controls. Specifically, the maximal clot firmness in the fibrin-based extrinsically activated test was almost twice the upper limit of normal in COVID patients, indicating a fibrin-mediated cause for hypercoagulability. To better understand the mechanism of this hypercoagulability we measured the components of the fibrinolytic pathways. Fibrinogen, tissue plasminogen activator and plasminogen activator inhibitor-1, but not plasminogen levels were elevated in patients with severe COVID-19. Our studies indicate that hypercoagulability in COVID-19 may be because of decreased fibrinolysis resulting from inhibition of plasmin through high levels of plasminogen activator inhibitor-1. Clinicians creating treatment protocols for anticoagulation in critically ill COVID-19 patients should consider these potential mechanisms of hypercoaguability.

Harmonized D-dimer levels upon admission for prognosis of COVID-19 severity: Results from a Spanish multicenter registry (BIOCOVID-Spain study)

Coagulopathy is a key feature of COVID-19 and D-dimer has been reported as a predictor of severity. However, because D-dimer test results vary considerably among assays, resolving harmonization issues is fundamental to translate findings into clinical practice. In this retrospective multicenter study (BIOCOVID study), we aimed to analyze the value of harmonized D-dimer levels upon admission for the prediction of in-hospital mortality in COVID-19 patients. All-cause in-hospital mortality was defined as endpoint. For harmonization of D-dimer levels, we designed a model based on the transformation of method-specific regression lines to a reference regression line. The ability of D-dimer for prediction of death was explored by receiver operating characteristic curves analysis and the association with the endpoint by Cox regression analysis. Study population included 2663 patients. In-hospital mortality rate was 14.3%. Harmonized D-dimer upon admission yielded an area under the curve of 0.66, with an optimal cut-off value of 0.945 mg/L FEU. Patients with harmonized D-dimer ≥ 0.945 mg/L FEU had a higher mortality rate (22.4% vs. 9.2%; p < 0.001). D-dimer was an independent predictor of in-hospital mortality, with an adjusted hazard ratio of 1.709. This is the first study in which a harmonization approach was performed to assure comparability of D-dimer levels measured by different assays. Elevated D-dimer levels upon admission were associated with a greater risk of in-hospital mortality among COVID-19 patients, but had limited performance as prognostic test.

Pattern of conventional coagulation and thromboelastographic parameters in patients with COVID-19 diseases and association of COVID-associated coagulopathy with mortality in intensive care unit

Background:

Knowledge of underlying pathophysiology of coagulopathy is evolving and the pattern of coagulation parameters in coronavirus disease 2019 (COVID-19)–associated diseases is still not very clear.

Aims:

In the present study, we aimed to find out the pattern and distribution of conventional coagulation parameters and thromboelastographic (TEG) parameters in COVID-19–associated coagulopathy (CAC) in survivors and nonsurvivors at 28 days.

Setting and Design:

The present prospective observational study was conducted at a tertiary care COVID-19 intensive care unit (ICU) facility from March 21, 2020, to July 15, 2021.

Materials and Methods:

Admission clinical and laboratory data (conventional coagulation, inflammatory and TEG parameters, and disease severity parameters) of 64 COVID-19 patients admitted to the ICU were collected. Patients were divided into two groups, i.e., survivors and nonsurvivors.

Statistical Analysis:

Data were compared between two groups, i.e., survivors versus no survivors on 28 days using Student's t-test/Mann–Whitney U-test or Chi-square test/Fisher's exact test.

Results:

Admission mean plasma fibrinogen levels (474.82 ± 167.41 mg.dL⁻¹) and D-dimer were elevated (1.78 [0.66, 3.62] mg.mL⁻¹) in the COVID-19 ICU patients. Overall, COVID-19 patients had mean lower normal platelet count (150 ± 50 × 10³ cells.mm⁻³), with marginally elevated prothrombin time (16.25 ± 3.76 s) and activated partial thromboplastin time (38.22 ± 16.72 s). A 65.6% (42/64) TEG profile analysis showed a normal coagulation profile, and the rest 21.9% (14/64) and 12.5% (8/64) had hypercoagulable and hypocoagulable states, respectively. Plasma D-dimer level was markedly elevated in nonsurvivors compared to survivors (P < 0.05), while no other conventional coagulation parameters and TEG profile demonstrated statistically significant between the two groups.

Conclusion:

Markedly elevated plasma D-dimer level was observed in nonsurvivors of COVID-19 ICU patients. A large portion of COVID-19 ICU patients had a normal TEG profile. Conventional coagulation parameters and TEG profile were similar between survivors and nonsurvivors.

Association of Lupus Anticoagulant status with Disease Course in SARS-CoV-2 (COVID-19) Infection

Background: We investigated the importance of lupus anticoagulant (LA) in patients with SARS-CoV-2. Methods: Medical records of 41 SARS-CoV-2 infected patients were reviewed. Patients were classified into two groups according to the frequency of positive LA test results: “LA (−)” and “LA (+) ≥1” (LA positive at least once). Statistical analysis was performed to determine the association between LA presence and change in LA test results and disease course according to both hospital days (HD) and days after diagnosis (DD). Results: The prevalence of LA was 51.2%. Averagely, the first change in LA test result occurred during DD 12-13 and between HD 9-10. The second change occurred on DD 15-16 and HD 13-14. The presence of LA was associated with severe disease (P = .004) but was not associated with thrombotic complications or mortality. The change of results from negative to positive or vice versa or the frequency of the changes was not associated with disease severity, thrombotic complications, or mortality. Conclusions: LA positivity can be regarded as one of the findings suggesting more serious SARS-CoV-2 infection.

Dilemma of Anticoagulation Therapy in Mild or Asymptomatic COVID-19 Cases

Severe acute respiratory distress syndrome coronavirus 2 (SARS-CoV-2) infection can be a life-threatening disease, which has emerged as a public health hazard. Thrombotic events have been reported in hospitalized patients with severe disease however scarce data is available regarding the screening of thromboembolic disease and pulmonary embolism in those with mild or asymptomatic infection. Herein, we describe the development of pulmonary embolism in two asymptomatic patients with COVID-19 and suggest the need for close monitoring and anticoagulation to prevent this life-threatening complication.

Adverse Outcome in COVID-19 Is Associated With an Aggravating Hypo-Responsive Platelet Phenotype

Thromboembolic complications are frequently observed in Coronavirus disease 2019 (COVID-19). While COVID-19 is linked to platelet dysregulation, the association between disease outcome and platelet function is less clear. We prospectively monitored platelet activation and reactivity in 97 patients during the first week of hospitalization and determined plasma markers of platelet degranulation and inflammation. Adverse outcome in COVID-19 was associated with increased basal platelet activation and diminished platelet responses, which aggravated over time. Especially GPIIb/IIIa responses were abrogated, pointing toward impeded platelet aggregation. Moreover, platelet-leukocyte aggregate formation was diminished, pointing toward abrogated platelet-mediated immune responses in COVID-19. No general increase in plasma levels of platelet-derived granule components could be detected, arguing against platelet exhaustion. However, studies on platelets from healthy donors showed that plasma components in COVID-19 patients with unfavorable outcome were at least partly responsible for diminished platelet responses. Taken together this study shows that unfavorable outcome in COVID-19 is associated with a hypo-responsive platelet phenotype that aggravates with disease progression and may impact platelet-mediated immunoregulation.

Characteristics of hemodialysis patient with critical COVID-19

INTRODUCTION

The clinical course of hemodialysis patients with COVID-19 still remains unclear.

METHODS

Thirty-four hemodialysis patients were retrospectively enrolled. Patients were divided according to disease severity, and clinical symptoms and laboratory data at admission were compared.

RESULTS

The serum C-reactive protein (CRP) level, d-dimer level, and white blood cell (WBC) count were significantly higher in the group with critical disease than in the group with mild to severe disease (p = 0.005, p = 0.039, and p = 0.045). The serum CRP level exceeded 10 mg/dl within 7 days of clinical onset in all the cases with critical disease.

CONCLUSION

Hemodialysis patients with COVID-19 who have elevated serum CRP and d-dimer levels, and an elevated WBC count at admission and patients with serum CRP levels exceeding 10 mg/dl before day 7 after clinical onset should be carefully monitored for possible progression to critical disease.

[Features of pathological anatomy of COVID-19 according to autopsy results in the Volgograd Region]

In connection with the ongoing pandemic of the novel coronavirus infection, the study of its morphopathology and the analysis of autopsy data are relevant. At the same time, attention should be paid to thromboses that play a significant role in the development of fatal outcomes in COVID-19, even taking into account the prescription of anticoagulant therapy to most patients.

OBJECTIVE

To make an assessment of morphological changes and a statistical analysis of the structure of mortality in COVID-19 on the basis of autopsy results in the Volgograd Region in 2020.

MATERIAL AND METHODS

The study was based on data from «The system for information on the work of the Volgograd Regional Autopsy Bureau» with a search for cases according to U07.1 code (the COVID-19 virus was identified) in January 1, 2020, to December 31, 2020, as well as on the autopsy materials of the Volgograd Regional Autopsy Bureau, and microscopic examination with photo fixation. Statistical processing was performed using the R programming language.

RESULTS

During the above period, 1119 deaths were identified with a confirmed diagnosis of COVID-19. Anatomopathological examination of the autopsy material showed that 77.54% of cases had blood clots mainly in the vessels of the pulmonary microvasculature, often only in the single veins during the applied anticoagulant therapy.

Analysis of variance indicated that the obtained result statistically significantly differed from the random distribution, and the probability of the presence of blood clots of specified localization was 3.17 times higher (CI 2.3-4.4; p<0.05) than their absence, as evidenced by logistic regression. In addition, perivascular and intra-alveolar diapedesis hemorrhages were noted in most fatal cases.

CONCLUSION

Thus, this investigation has revealed that the high frequency of thrombosis detected in the presence of perivascular and intra-alveolar diapedesis hemorrhages in COVID-19 confirms the tendency of patients with a severe course of the disease to manifest hemostatic disorders, significant blood vascular endothelial injury, and obvious vascular impermeability.

Brachial Artery Thrombosis in a Covid-19 Positive Patient with Thoracic Outlet Syndrome

Severe coronavirus disease 2019 (COVID-19) has been complicated by coagulopathy and thrombotic events including venous thromboembolism, pulmonary embolism, and arterial thrombus at a rate higher than has traditionally been seen with sepsis-induced coagulopathy or disseminated intravascular coagulation leading most centers to treat hospitalized patients with prophylactic anticoagulation. We present a case of a patient with thoracic outlet syndrome who presents with brachial artery thrombosis in the setting of infection with COVID-19. Both thoracic outlet syndrome and COVID-19 infection are independently associated with increased risk of thrombotic events. The induced hypercoagulable state from COVID-19 infection may result in acute arterial thrombosis in patients with predisposing anatomic differences consistent with thoracic outlet syndrome. Level of Evidence: V.

COVID-19 and coagulopathy

The SARS-CoV-2 is a new coronavirus responsible for the COVID-19 disease and has caused the pandemic worldwide. A large number of cases have overwhelmed the healthcare system worldwide. The COVID-19 infection has been associated with a heightened risk of thromboembolic complications. Various mechanisms are leading to the high thrombotic risk in COVID-19 patients such as inflammation, endotheliitis, hyperviscosity, and hypercoagulability. We searched PubMed, EMBASE, and CINAHL from January 2020 to December 2020. We used the following search terms: COVID-19, coagulopathy, and thrombosis. We reviewed the epidemiology, clinical features, mechanisms, and treatment of COVID-19-associated coagulopathy.

COVID-19 and immunothrombosis: Pathophysiology and therapeutic implications

The coagulopathy of COVID-19 is characterised by significantly elevated D Dimer and fibrinogen, mild thrombocytopenia and a mildly prolonged PT/APTT. A high incidence of thrombotic complications occurs despite standard thromboprophylaxis. The evidence to date supports immunothrombosis as the underlying mechanism for this coagulopathy which is triggered by a hyperinflammatory response and endotheliopathy. A hypercoagulable state results from endothelial damage/activation, complement activation, platelet hyperactivity, release of Extracellular Neutrophil Traps, activation of the coagulation system and a "hypofibrinolytic" state. Significant cross-talk occurs between the innate/adaptive immune system, endothelium and the coagulation system. D dimer has been shown to be the most reliable predictor of disease severity, thrombosis, and overall survival. In this context, targeting pathways upstream of coagulation using novel or repurposed drugs alone or in combination with other anti-thrombotic agents may be a rational approach to prevent the mortality/morbidity due to COVID-19 associated coagulopathy.

Anti-prothrombin autoantibodies enriched after infection with SARS-CoV-2 and influenced by strength of antibody response against SARS-CoV-2 proteins

Antiphospholipid antibodies (aPL), assumed to cause antiphospholipid syndrome (APS), are notorious for their heterogeneity in targeting phospholipids and phospholipid-binding proteins. The persistent presence of Lupus anticoagulant and/or aPL against cardiolipin and/or β2-glycoprotein I have been shown to be independent risk factors for vascular thrombosis and pregnancy morbidity in APS. aPL production is thought to be triggered by-among other factors-viral infections, though infection-associated aPL have mostly been considered non-pathogenic. Recently, the potential pathogenicity of infection-associated aPL has gained momentum since an increasing number of patients infected with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has been described with coagulation abnormalities and hyperinflammation, together with the presence of aPL. Here, we present data from a multicentric, mixed-severity study including three cohorts of individuals who contracted SARS-CoV-2 as well as non-infected blood donors. We simultaneously measured 10 different criteria and non-criteria aPL (IgM and IgG) by using a line immunoassay. Further, IgG antibody response against three SARS-CoV-2 proteins was investigated using tripartite automated blood immunoassay technology. Our analyses revealed that selected non-criteria aPL were enriched concomitant to or after an infection with SARS-CoV-2. Linear mixed-effects models suggest an association of aPL with prothrombin (PT). The strength of the antibody response against SARS-CoV-2 was further influenced by SARS-CoV-2 disease severity and sex of the individuals. In conclusion, our study is the first to report an association between disease severity, anti-SARS-CoV-2 immunoreactivity, and aPL against PT in patients with SARS-CoV-2.

Crohn's and Colitis Canada's 2021 Impact of COVID-19 and Inflammatory Bowel Disease in Canada: Seniors With IBD

The risk of hospitalization and death from Coronavirus disease-19 (COVID-19) increases with age. The extreme elderly have been particularly vulnerable, with those above the age of 80 having a case-fatality rate as high as 15%. Aging of the immune system can lead to impaired inflammatory responses where eradication of an organism such as Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV2) is inadequate but is exaggerated in such a way as to enhance pneumonia and acute respiratory distress syndrome. Frailty and comorbidity are both more common in the elderly, and these can enhance the morbidity and mortality from COVID-19. Studies from Northern California and Italy suggest that elderly persons with inflammatory bowel disease (IBD) were more likely to acquire SARS-CoV-2 infection than youths with IBD. While the specific impact of age-related comorbidity is less well established among people with IBD who acquire COVID-19, data from the Surveillance Epidemiology of Coronavirus Under Research Exclusion (SECURE-IBD) database reported that having two or more chronic illnesses was independently associated with developing severe COVID-19 among people with IBD. Despite having exaggerated auto-inflammatory responses, people with IBD do not appear to have an overall increased risk of developing severe COVID-19 than the general population. However, whether seniors with IBD do worse once they acquire COVID-19 compared with seniors without IBD is not known. The advent of telehealth care has posed an information technology challenge for many seniors with and without IBD. Most persons with IBD have expressed satisfaction with virtual IBD health care (phone or video-based visits). While the elderly may have less robust immune responses to vaccinations, learning from experiences with other vaccination programs, especially influenza, have shown that vaccinating seniors decreases both morbidity and mortality and, in turn, healthcare resources.

Native and transplant kidney histopathological manifestations in association with COVID-19 infection: A systematic review

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can result in clinically significant multi-system disease including involvement in the kidney. The underlying histopathological processes were unknown at the start of the pandemic. As case reports and series have been published describing the underlying renal histopathology from kidney biopsies, we have started to gain an insight into the renal manifestations of this novel disease.

AIM

To provide an overview of the current literature on the renal histopathological features and mechanistic insights described in association with coronavirus disease 2019 (COVID-19) infection.

METHODS

A systematic review was performed by conducting a literature search in the following websites-‘PubMed’, ‘Web of Science’, ‘Embase’ and ‘Medline-ProQuest’ with the following search terms-“COVID-19 AND kidney biopsy”, “COVID-19 AND renal biopsy”, “SARS-CoV-2 AND kidney biopsy” and “SARS-CoV-2 AND renal biopsy”. We have included published data up until February 15, 2021, which includes kidney biopsies (native, transplant and postmortem) from patients with COVID-19. Data on clinical presentation, histopathological features, management and outcome was extracted from the reported studies.

RESULTS

The total number of biopsies reported on here is 288, of which 189 are postmortem, 84 native and 15 transplants. The results are varied and show underlying pathologies ranging from collapsing glomerulopathy and acute tubular injury (ATI) to anti-nuclear cytoplasmic antibody associated vasculitis and pigment nephropathy. There was variation in the specific treatment used for the various renal conditions, which included steroids, hydroxychloroquine, eculizumab, convalescent plasma, rituximab, anakinra, cyclophosphamide and renal replacement therapy, amongst others. The pathological process which occurs in the kidney following COVID-19 infection and leads to the described biopsy findings has been hypothesized in some conditions but not others (for example, sepsis related hypoperfusion for ATI). It is important to note that this represents a very small minority of the total number of cases of COVID-19 related kidney disease, and as such there may be inherent selection bias in the results described. Further work will be required to determine the pathogenetic link, if any, between COVID-19 and the other renal pathologies.

CONCLUSION

This report has clinical relevance as certain renal pathologies have specific management, with the implication that kidney biopsy in the setting of renal disease and COVID-19 should be an early consideration, dependent upon the clinical presentation.

The Pathophysiology and Management of Diabetic Ketoacidosis in COVID-19 Patients: A Literature Review

Diabetic individuals are considered a vulnerable population during the COVID-19 Pandemic, and several studies noted worse outcomes, including death, among those who get infected. Diabetic emergencies, such as ketoacidosis (DKA), are common and potentially life-threatening conditions in uncontrolled patients. While the pathophysiological background of the relationship between COVID-19 and DKA is not fully understood, early reports available so far indicate that patients with pre-existing diabetes who get infected with the SARS-CoV 2 virus are at higher risk of DKA. It was also suggested that DKA is a poor prognostic sign for infected patients, these being at higher risk of developing worse forms of COVID-19 disease and having high mortality. Therefore, healthcare personnel dealing with such patients face a considerable challenge, as the correct and safe emergency management of such cases is far from established. This article aimed to conduct a study that reviews the current published data available about patients with DKA and COVID-19.

To clot or not to clot? Ad is the question-Insights on mechanisms related to vaccine-induced thrombotic thrombocytopenia

Vaccine-induced immune thrombotic thrombocytopenia (VITT) has caused global concern. VITT is characterized by thrombosis and thrombocytopenia following COVID-19 vaccinations with the AstraZeneca ChAdOx1 nCov-19 and the Janssen Ad26.COV2.S vaccines. Patients present with thrombosis, severe thrombocytopenia developing 5-24 days following first dose of vaccine, with elevated D-dimer, and PF4 antibodies, signifying platelet activation. As of June 1, 2021, more than 1.93 billion COVID-19 vaccine doses had been administered worldwide. Currently, 467 VITT cases (0.000024%) have been reported across the UK, Europe, Canada, and Australia. Guidance on diagnosis and management of VITT has been reported but the pathogenic mechanism is yet to be fully elucidated. Here, we propose and discuss potential mechanisms in relation to adenovirus induction of VITT. We provide insights and clues into areas warranting investigation into the mechanistic basis of VITT, highlighting the unanswered questions. Further research is required to help solidify a pathogenic model for this condition.

Clinical Features and Factors Associated with Occult Gastrointestinal Bleeding in COVID-19 Patients

Background

There has been an increasing number of COVID-19 patients around the world. Since some patients developed with gastrointestinal bleeding, our study focused on the clinical features and gastroscopic findings of these patients, and factors associated with occult gastrointestinal bleeding.

Patients and Methods

In this retrospective, observational study, we collected 368 COVID-19 patients who performed fecal or gastric occult blood from Wuhan Tongji Hospital, Jin Yin-tan Hospital, and Wuhan Union Hospital between February 1, 2020 and March 6, 2020. Clinical features were compared between patients with or without occult gastrointestinal bleeding, and gastroscopic findings of seven patients were described. Logistic regression analyses were performed to explore the factors associated with occult gastrointestinal bleeding.

Results

In total, 43 (11.7%) patients presented occult gastrointestinal bleeding, whereas 35 (81.4%) of severe cases. CRP level, prothrombin time and D-dimer were higher, while lymphocyte count and albumin levels were decreased in patients with occult gastrointestinal bleeding. Gastroscopy in seven COVID-19 patients showed mucosal congestion, erosion or scattered bleeding at different sites. Albumin levels (OR, 0.856 [95% CI 0.793–0.924]; p < 0.001), prothrombin time (OR, 1.267 [1.089–1.475]; p = 0.002) on admission and severe disease (OR, 4.157 [1.765–9.791]; p = 0.001) were independent factors associated with GIB in COVID-19 patients, while antiviral drugs and glucocorticoid therapy were not associated with it.

Conclusion

COVID-19 patients with occult gastrointestinal bleeding suffered from worse prognosis. Patients with decreased serum albumin levels or prolonged prothrombin time, and severe cases were at higher risk of occult gastrointestinal bleeding.

American Society of Hematology living guidelines on the use of anticoagulation for thromboprophylaxis in patients with COVID-19: May 2021 update on the use of intermediate-intensity anticoagulation in critically ill patients

BACKGROUND

COVID-19-related critical illness is associated with an increased risk of venous thromboembolism (VTE).

OBJECTIVE

These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in making decisions about the use of anticoagulation for thromboprophylaxis in patients with COVID-19-related critical illness who do not have confirmed or suspected VTE.

METHODS

ASH formed a multidisciplinary guideline panel that included 3 patient representatives and applied strategies to minimize potential bias from conflicts of interest. The McMaster University Grading of Recommendations Assessment, Development and Evaluation (GRADE) Centre supported the guideline development process by performing systematic evidence reviews (up to 5 March 2021). The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the GRADE approach to assess evidence and make recommendations, which were subject to public comment. This is an update on guidelines published in February 2021.

RESULTS

The panel agreed on 1 additional recommendation. The panel issued a conditional recommendation in favor of prophylactic-intensity over intermediate-intensity anticoagulation in patients with COVID-19-related critical illness who do not have confirmed or suspected VTE.

CONCLUSIONS

This recommendation was based on low certainty in the evidence, which underscores the need for additional high-quality, randomized, controlled trials comparing different intensities of anticoagulation in critically ill patients. Other key research priorities include better evidence regarding predictors of thrombosis and bleeding risk in critically ill patients with COVID-19 and the impact of nonanticoagulant therapies (eg, antiviral agents, corticosteroids) on thrombotic risk.

An interactive single cell web portal identifies gene and cell networks in COVID-19 host responses

Numerous studies have provided single-cell transcriptome profiles of host responses to SARS-CoV-2 infection. Critically lacking however is a data mine that allows users to compare and explore cell profiles to gain insights and develop new hypotheses. To accomplish this, we harmonized datasets from COVID-19 and other control condition blood, bronchoalveolar lavage, and tissue samples, and derived a compendium of gene signature modules per cell type, subtype, clinical condition, and compartment. We demonstrate approaches to interacting with, exploring, and functional evaluating these modules via a new interactive web portal ToppCell (http://toppcell.cchmc.org/). As examples, we develop three hypotheses: (1) alternatively-differentiated monocyte-derived macrophages form a multicelllar signaling cascade that drives T cell recruitment and activation; (2) COVID-19-generated platelet subtypes exhibit dramatically altered potential to adhere, coagulate, and thrombose; and (3) extrafollicular B maturation is driven by a multilineage cell activation network that expresses an ensemble of genes strongly associated with risk for developing post-viral autoimmunity.

Angiotensin II receptor blocker intake associates with reduced markers of inflammatory activation and decreased mortality in patients with cardiovascular comorbidities and COVID-19 disease

AIMS

Patients with cardiovascular comorbidities have a significantly increased risk for a critical course of COVID-19. As the SARS-CoV2 virus enters cells via the angiotensin-converting enzyme receptor II (ACE2), drugs which interact with the renin angiotensin aldosterone system (RAAS) were suspected to influence disease severity.

METHODS AND RESULTS

We analyzed 1946 consecutive patients with cardiovascular comorbidities or hypertension enrolled in one of the largest European COVID-19 registries, the Lean European Open Survey on SARS-CoV-2 (LEOSS) registry. Here, we show that angiotensin II receptor blocker intake is associated with decreased mortality in patients with COVID-19 [OR 0.75 (95% CI 0,59-0.96; p = 0.013)]. This effect was mainly driven by patients, who presented in an early phase of COVID-19 at baseline [OR 0,64 (95% CI 0,43-0,96; p = 0.029)]. Kaplan-Meier analysis revealed a significantly lower incidence of death in patients on an angiotensin receptor blocker (ARB) (n = 33/318;10,4%) compared to patients using an angiotensin-converting enzyme inhibitor (ACEi) (n = 60/348;17,2%) or patients who received neither an ACE-inhibitor nor an ARB at baseline in the uncomplicated phase (n = 90/466; 19,3%; p<0.034). Patients taking an ARB were significantly less frequently reaching the mortality predicting threshold for leukocytes (p<0.001), neutrophils (p = 0.002) and the inflammatory markers CRP (p = 0.021), procalcitonin (p = 0.001) and IL-6 (p = 0.049). ACE2 expression levels in human lung samples were not altered in patients taking RAAS modulators.

CONCLUSION

These data suggest a beneficial effect of ARBs on disease severity in patients with cardiovascular comorbidities and COVID-19, which is linked to dampened systemic inflammatory activity.

Development of Arterial Thrombosis in a Patient on Therapeutic Anticoagulation for COVID-19

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV2) virus has been known to manifest various non-pulmonary complications in the affected patient, including both venous and less frequently, arterial thrombosis. Ongoing research is necessary to determine who might benefit from therapeutic anticoagulation as well as potentially develop an algorithm to predict thromboembolic events in this patient population. We present a case of a 65-year-old man with a past medical history of hypertension, diabetes type 2, and a previous cerebrovascular accident who was admitted with acute hypoxemic respiratory failure due to coronavirus disease 2019 (COVID-19). On admission to the hospital, the patient was initiated on therapeutic anticoagulation. Subsequently, he developed left lower limb ischemia. Imaging discovered arterial thrombosis in the bilateral deep femoral and left popliteal arteries. Consequently, the patient required catheter directed thrombolysis for partial reperfusion. Unfortunately, the patient succumbed to the complications of COVID-19. This case is notable in that it highlights the arterial thrombophilia associated with COVID-19 despite early intervention with therapeutic anticoagulation.

Intriguing findings of liver fibrosis following COVID-19

Background

Studies on a new coronavirus disease (COVID-19) show the elevation of liver enzymes and liver fibrosis index (FIB-4) independently on pre-existing liver diseases. It points to increased liver fibrogenesis during acute COVID-19 with possible long-term consequences. This study aimed to assess liver fibrosis in COVID-19 patients by serum hyaluronic acid (HA) and FIB-4.

Methods

The study included the acute COVID-19 group (66 patients, 50% females, mean age 58.3 ± 14.6), the post-COVID group (58 patients in 3–6 months after the recovery, 47% females, mean age 41.2 ± 13.4), and a control group (17 people, 47% females, mean age 42.8 ± 11.0). Ultrasound elastography was performed in the post-COVID and control groups.

Results

Sixty-five percent of the acute COVID-19 group had increased FIB-4 (> 1.45), and 38% of patients had FIB-4 ≥ 3.25. After matching by demographics, 52% of acute COVID-19 and 5% of the post-COVID group had FIB-4 > 1.45, and 29% and 2% of patients had FIB-4 ≥ 3.25, respectively. Increased serum HA (≥ 75 ng/ml) was observed in 54% of the acute COVID-19 and 15% of the post-COVID group. In the acute COVID-19 group, HA positively correlated with FIB-4, AST, ALT, LDH, IL-6, and ferritin and negatively with blood oxygen saturation. In the post-COVID group, HA did not correlate with FIB-4, but it was positively associated with higher liver stiffness and ALT.

Conclusion

More than half of acute COVID-19 patients had increased serum HA and FIB-4 related to liver function tests, inflammatory markers, and blood oxygen saturation. It provides evidence for the induction of liver fibrosis by multiple factors during acute COVID-19. Findings also indicate possible liver fibrosis in about 5% of the post-COVID group.

Gender Characteristics of the Novel Coronavirus Infection (COVID-19) in Middle-Aged Adults

The aim of the study is to assess the gender-related specifics of the COVID-19 course in patients under 55 years of age.

Platelets in the perspective of COVID-19; pathophysiology of thrombocytopenia and its implication as prognostic and therapeutic opportunity

Despite endorsed and exponential research to improve diagnostic and therapeutic strategies, efforts have not yet converted into a better prospect for patients infected with the novel coronavirus (2019nCoV), and still, the name of SARS-CoV-2 is coupled with numerous unanswered questions. One of these questions is concerning how this respiratory virus reduces the number of platelets (PLTs)? The results of laboratory examinations showed that about a quarter of COVID-19 cases experience thrombocytopenia, and more remarkably, about half of these patients succumb to the infection due to coagulopathy. These findings have positioned PLTs as a pillar in the management as well as stratifying COVID-19 patients; however, not all the physicians came into a consensus about the prognostic value of these cells. The current review aims to unravel the contributory role of PLTs s in COVID-19; and alsoto summarize the original data obtained from international research laboratories on the association between COVID-19 and PLT production, activation, and clearance. In addition, we provide a special focus on the prognostic value of PLTs and their related parameters in COVID-19. Questions on how SARS-CoV-2 induces thrombocytopenia are also responded to. The last section provides a general overview of the most recent PLT- or thrombocytopenia-related therapeutic approaches. In conclusion, since SARS-CoV-2 reduces the number of PLTs by eliciting different mechanisms, treatment of thrombocytopenia in COVID-19 patients is not as simple as it appears and serious cautions should be considered to deal with the problem through scrutiny awareness of the causal mechanisms.

COVID19 Disease Map, a computational knowledge repository of virus-host interaction mechanisms

We need to effectively combine the knowledge from surging literature with complex datasets to propose mechanistic models of SARS-CoV-2 infection, improving data interpretation and predicting key targets of intervention. Here, we describe a large-scale community effort to build an open access, interoperable and computable repository of COVID-19 molecular mechanisms. The COVID-19 Disease Map (C19DMap) is a graphical, interactive representation of disease-relevant molecular mechanisms linking many knowledge sources. Notably, it is a computational resource for graph-based analyses and disease modelling. To this end, we established a framework of tools, platforms and guidelines necessary for a multifaceted community of biocurators, domain experts, bioinformaticians and computational biologists. The diagrams of the C19DMap, curated from the literature, are integrated with relevant interaction and text mining databases. We demonstrate the application of network analysis and modelling approaches by concrete examples to highlight new testable hypotheses. This framework helps to find signatures of SARS-CoV-2 predisposition, treatment response or prioritisation of drug candidates. Such an approach may help deal with new waves of COVID-19 or similar pandemics in the long-term perspective.

Coronavirus disease 2019 and stroke

The multisystem nature of coronavirus disease 2019 has become increasingly clear over the course of the pandemic. Both the neurological and vascular systems are affected, impacting acute stroke. This impact can be conceptualised as direct and indirect effects of the disease. The direct effects of coronavirus disease 2019 on stroke are thought to relate to receptor-mediated tissue invasion and the marked inflammatory response to the presence of the virus. These effects include coagulopathies, endotheliitis, systemic inflammation and atherosclerotic plaque instability, with possibly long-term cardiovascular effects. The indirect effects impact all aspects of stroke care delivery. These extend far beyond the direct effects of coronavirus disease 2019, and represent an essential focus for stroke systems of care. In this article, we detail the impact of coronavirus disease 2019 on acute stroke.

Liver-Dependent Lung Remodeling during Systemic Inflammation Shapes Responses to Secondary Infection

Systemic duress, such as that elicited by sepsis, burns, or trauma, predisposes patients to secondary pneumonia, demanding better understanding of host pathways influencing this deleterious connection. These pre-existing circumstances are capable of triggering the hepatic acute-phase response (APR), which we previously demonstrated is essential for limiting susceptibility to secondary lung infections. To identify potential mechanisms underlying protection afforded by the lung-liver axis, our studies aimed to evaluate liver-dependent lung reprogramming when a systemic inflammatory challenge precedes pneumonia. Wild-type mice and APR-deficient littermate mice with hepatocyte-specific deletion of STAT3 (hepSTAT3-/-), a transcription factor necessary for full APR initiation, were challenged i.p. with LPS to induce endotoxemia. After 18 h, pneumonia was induced by intratracheal Escherichia coli instillation. Endotoxemia elicited significant transcriptional alterations in the lungs of wild-type and hepSTAT3-/- mice, with nearly 2000 differentially expressed genes between genotypes. The gene signatures revealed exaggerated immune activity in the lungs of hepSTAT3-/- mice, which were compromised in their capacity to launch additional cytokine responses to secondary infection. Proteomics revealed substantial liver-dependent modifications in the airspaces of pneumonic mice, implicating a network of dispatched liver-derived mediators influencing lung homeostasis. These results indicate that after systemic inflammation, liver acute-phase changes dramatically remodel the lungs, resulting in a modified landscape for any stimuli encountered thereafter. Based on the established vulnerability of hepSTAT3-/- mice to secondary lung infections, we believe that intact liver function is critical for maintaining the immunological responsiveness of the lungs.

Skin Failure Among Critically Ill Patients Afflicted with Coronavirus Disease 2019 (COVID-19)

Objective: To characterize skin integrity among coronavirus disease 2019 (COVID-19) patients treated in the intensive care unit (ICU), and identify risk factors for skin failure (SF) in these patients. Design: The characteristic, profound pro-inflammatory, hypercoagulable state of COVID-19 is manifested by the high severity of illness and extensive organ dysfunction observed in these patients. SF in critically ill patients, although described previously, exhibits a uniquely complex pathogenesis in this population. Patients: Retrospective review of all COVID-19 patients (confirmed positive for severe acute respiratory syndrome coronavirus-2 [SARS-CoV-2]) admitted to a single surgical ICU for at least 48 hours between March-June 2020. Interventions: Data were extracted from a COVID-19 institutional data repository that harvested data from electronic health records and other clinical data sources. Demographics; coagulation/inflammation biomarkers; number, location, and stage of SF lesions; resource utilization; and outcomes were captured. Measurements and Main Results: 64 patients met inclusion criteria; 51 (80%) developed SF (SF+ ). Forty-three (85%) developed stage 3 or higher SF (χ²  =  22.66, P < .0001). Thirty-nine of 51 (76%) SF+ patients developed more than one SF lesion (χ²  =  13.26, P  =  .0003). SF+ patients manifested a profound pro-inflammatory, hypercoagulable phenotype (lower serum albumin and higher ferritin, interleukin [IL]-6 and D-dimer concentrations [all, P < .001]). Durations of mechanical ventilation, vasopressor therapy, and ICU length of stay were significantly longer (all, P < .05) in the SF + patients. Conclusions: The unique characteristics of COVID-19 dermatopathology and the strong correlation between markers of inflammation and development of SF reflect COVID-19-related organ dysfunction and its deleterious effects on the microcirculation. Considering that skin is invaded directly by SARS-CoV-2 and affected by COVID-19-related immune complex deposition and microthrombosis, SF may reflect disease as opposed to pressure injuries related to processes of care. In the context of COVID-19 critical illness, SF should not be considered a "never event."

Characterization by Quantitative Serum Proteomics of Immune-Related Prognostic Biomarkers for COVID-19 Symptomatology

The COVID-19 pandemic caused by SARS-CoV-2 challenges the understanding of factors affecting disease progression and severity. The identification of prognostic biomarkers and physiological processes associated with disease symptoms is relevant for the development of new diagnostic and therapeutic interventions to contribute to the control of this pandemic. To address this challenge, in this study, we used a quantitative proteomics together with multiple data analysis algorithms to characterize serum protein profiles in five cohorts from healthy to SARS-CoV-2-infected recovered (hospital discharge), nonsevere (hospitalized), and severe [at the intensive care unit (ICU)] cases with increasing systemic inflammation in comparison with healthy individuals sampled prior to the COVID-19 pandemic. The results showed significantly dysregulated proteins and associated biological processes and disorders associated to COVID-19. These results corroborated previous findings in COVID-19 studies and highlighted how the representation of dysregulated serum proteins and associated BPs increases with COVID-19 disease symptomatology from asymptomatic to severe cases. The analysis was then focused on novel disease processes and biomarkers that were correlated with disease symptomatology. To contribute to translational medicine, results corroborated the predictive value of selected immune-related biomarkers for disease recovery [Selenoprotein P (SELENOP) and Serum paraoxonase/arylesterase 1 (PON1)], severity [Carboxypeptidase B2 (CBP2)], and symptomatology [Pregnancy zone protein (PZP)] using protein-specific ELISA tests. Our results contributed to the characterization of SARS-CoV-2–host molecular interactions with potential contributions to the monitoring and control of this pandemic by using immune-related biomarkers associated with disease symptomatology.

Systemic inflammation in COVID‐19 patients may induce various types of venous and arterial thrombosis: A systematic review

COVID‐19 is a global pandemic with a daily increasing number of affected individuals. Thrombosis is a severe complication of COVID‐19 that leads to a worse clinical course with higher rates of mortality. Multiple lines of evidence suggest that hyperinflammation plays a crucial role in disease progression. This review compiles clinical data of COVID‐19 patients who developed thrombotic complications to investigate the possible role of hyperinflammation in inducing hypercoagulation. A systematic literature search was performed using PubMed, Embase, Medline and Scopus to identify relevant clinical studies that investigated thrombotic manifestations and reported inflammatory and coagulation biomarkers in COVID‐19 patients. Only 54 studies met our inclusion criteria, the majority of which demonstrated significantly elevated inflammatory markers. In the cohort studies with control, D‐dimer was significantly higher in COVID‐19 patients with thrombosis as compared to the control. Pulmonary embolism, deep vein thrombosis and strokes were frequently reported which could be attributed to the hyperinflammatory response associated with COVID‐19 and/or to the direct viral activation of platelets and endothelial cells, two mechanisms that are discussed in this review. It is recommended that all admitted COVID‐19 patients should be assessed for hypercoagulation. Furthermore, several studies have suggested that anticoagulation may be beneficial, especially in hospitalized non‐ICU patients. Although vaccines against SARS‐CoV‐2 have been approved and distributed in several countries, research should continue in the field of prevention and treatment of COVID‐19 and its severe complications including thrombosis due to the emergence of new variants against which the efficacy of the vaccines is not yet clear.

[COVID-19-associated stroke]

Neurological complications of COVID-19 occur in almost a third of patients. According to various studies, the frequency of cerebrovascular manifestations in patients with a positive test result for SARS-CoV-2 ranges from 1% to 3%. The most common manifestation was acute ischemic stroke. Cerebrovascular complications in COVID-19 patients are likely multifactorial. They can be associated with coagulopathy, systemic inflammatory response, endothelial dysfunction and microthrombosis, as well as organ failure, impaired cardiac functions. The peculiarities of stroke in patients with COVID-19 include occlusion of large vessels, involvement of several vascular pools, a high incidence of damage to the vertebrobasilar system, a cryptogenic nature and a high severity of the course with high mortality and disability. Particular attention should be paid to impaired cognitive functions as a clinical manifestation of the consequences of stroke associated with a new coronavirus infection.

COVID-19 and features of cardiovascular involvement

The article provides an overview of current information on the pathogenesis of COVID-19 and organ-specific lesions developing in this disease. The data on inflammation and its biochemical markers, on the features of coagulopathy, endothelial damage and microthrombosis are presented in detail. Particular attention is paid to the role of receptors for angiotensin converting enzyme type 2 and transmembrane serine protease type 2 in the development of organ-specific lesions in COVID-19. The pathogenesis of damage to the cardiovascular system is considered in detail with the presentation of data from foreign literature on changes in the myocardium and the author's results of transthoracic echocardiographic examination in patients who have undergone COVID-19.

Phlegmasia cerulea dolens superimposed on disseminated intravascular coagulation in COVID-19

COVID-19 infection has several cardiovascular implications, and coagulopathy is a common abnormality in these patients, often coupled with elevated plasma fibrinogen and D-dimer levels, contributing to adverse outcomes. Phlegmasia cerulea dolens (PCD) is a rare manifestation of deep vein thrombosis. It is life-threatening and can rapidly lead to venous gangrene of the extremity. Only a few cases of COVID-19 associated with PCD are reported in the literature, despite thromboembolism being the common paradigm between the two diseases. We present the case of a 64-year-old adult with acute severe COVID-19 pneumonia who developed PCD despite constantly elevated activated partial thromboplastin time and international normalized ratio. (www.actabiomedica.it)

Placental Thrombus After Maternal COVID-19 Infection: A Case Study

A 34-year-old patient developed an area of thrombus within her placenta. This resulted in severe fetal growth restriction which physicians felt was due to contracting and recovering from the coronavirus disease (COVID-19), during her pregnancy. Serial sonograms demonstrated a slowing of fetal growth and an area of thrombosis within the placenta. This was confirmed by pathologic examination of the placenta after delivery. Since COVID-19 and pregnancy are both known hypercoagulable states, it is vital for the ultrasonographer to recognize thrombosis in the placenta. It is also important to understand the possible pregnancy outcomes, based on the location and appearance of a nonvascular placental lesion.

COVID-19 as a cause of chronic pulmonary hypertension: pathophysiological rationale and potential of instrumental investigations

Coronavirus disease 2019 (COVID-19) is a poorly understood and dangerous medical problem. COVID-19-related pulmonary vessels involvement is a complex set of interrelated pathophysiological processes associated with vascular endothelial dysfunction and accompanied by thrombosis of various localization, vasomotor disorders, severe respiratory failure, as well as pulmonary embolism (PE) resulting in chronic thromboembolic pulmonary hypertension (CTEPH). According to computed tomographic pulmonary angiography, the incidence of PE in patients with COVID-19 ranges from 23 to 30%. The aim of this work was to focus the doctors' attention on the risk of pulmonary hypertension in patients after COVID-19.

Despite the ability of severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) to infect various organs and systems, the main and most serious complications are pulmonary infiltration, acute respiratory distress syndrome, acute respiratory failure and PE, which in some cases becomes the triggering mechanism for CTEPH development. The literature review presents data on main pathological abnormalities developing in target organs during COVID-19 and playing an important role in increasing the CTEPH risk. The paper describes the main methods of instrumental investigations of CTEPH and an algorithm for its use in COVID-19 survivors.

The revealed data demonstrated that the absence of obvious signs of pulmonary hypertension/CTEPH, the cardiopulmonary system abnormalities cannot be ruled out. Therefore, it seems appropriate to actively follow up COVID-19 survivors. A thoroughly, purposefully collected anamnesis, pulmonary function tests and stress echocardiography in an ambiguous clinical situation will play a leading role as they identify cardiopulmonary disorders and provide the doctor with basic information for further planning of patient management.

Extracellular Vesicles and Thrombosis: Update on the Clinical and Experimental Evidence

Extracellular vesicles (EVs) compose a heterogenous group of membrane-derived particles, including exosomes, microvesicles and apoptotic bodies, which are released into the extracellular environment in response to proinflammatory or proapoptotic stimuli. From earlier studies suggesting that EV shedding constitutes a cellular clearance mechanism, it has become evident that EV formation, secretion and uptake represent important mechanisms of intercellular communication and exchange of a wide variety of molecules, with relevance in both physiological and pathological situations. The putative role of EVs in hemostasis and thrombosis is supported by clinical and experimental studies unraveling how these cell-derived structures affect clot formation (and resolution). From those studies, it has become clear that the prothrombotic effects of EVs are not restricted to the exposure of tissue factor (TF) and phosphatidylserines (PS), but also involve multiplication of procoagulant surfaces, cross-linking of different cellular players at the site of injury and transfer of activation signals to other cell types. Here, we summarize the existing and novel clinical and experimental evidence on the role and function of EVs during arterial and venous thrombus formation and how they may be used as biomarkers as well as therapeutic vectors.

Specific Features of the Coagulopathy Signature in Severe COVID-19 Pneumonia

Rationale: COVID-19 displays distinct characteristics that suggest a unique pathogenesis. The objective of this study was to compare biomarkers of coagulopathy and outcomes in COVID-19 and non-COVID-19 patients with severe pneumonia. Methods: Thirty-six non-COVID-19 and 27 COVID-19 non-immunocompromised patients with severe pneumonia were prospectively enrolled, most requiring intensive care. Clinical and biological characteristics (including plasma biomarkers of coagulopathy) were compared. Results: At similar baseline severity, COVID-19 patients required mechanical ventilation (MV) for significantly longer than non-COVID-19 patients (p = 0.0049) and more frequently developed venous thrombotic complications (p = 0.031). COVID-19 patients had significantly higher plasma concentrations of soluble VCAM1 (sVCAM1) (5,739 ± 3,293 vs. 3,700 ± 2,124 ng/ml; p = 0.009), but lower levels of D-dimers, vWF-A2, sICAM1, sTREM1, VEGF, and P-selectin, compared to non-COVID-19 patients. Principal component analysis identified two main patterns, with a clear distinction between non-COVID-19 and COVID-19 patients. Multivariable regression analysis confirmed that sVCAM1 rising levels were independently associated with a longer duration of MV. Finally, we identified close correlations between sVCAM1 and some features of COVID-19 immune dysregulation (ie. CXCL10, GM-CSF, and IL-10). Conclusion: We identified specific features of the coagulopathy signature in severe COVID-19 patients, with higher plasma sVCAM1 levels, that were independently associated with the longer duration of mechanical ventilation. Clinical Trial Registration:ClinicalTrials.gov, identifier: NCT03505281.

Case Report: Prolonged VV-ECMO (111 Days) Support in a Patient With Severe COVID-19

Venovenous extracorporeal membrane oxygenation (VV-ECMO) may be a lifesaving rescue therapy for patients with severe coronavirus disease 2019 (COVID-19). However, little is known regarding the efficacy of prolonged ECMO (duration longer than 14 days) in patients with COVID-19. In this case report, we report the successful use of prolonged VV-ECMO (111 days) in a 61-year-old man with severe COVID-19. Given the high mortality rate of severe COVID-19, this case provided evidence for use of prolonged VV-ECMO as supportive care in patients with severe COVID-19.

Neurological symptoms and complications in predominantly hospitalized COVID-19 patients: Results of the European multinational Lean European Open Survey on SARS-Infected Patients (LEOSS)

Background and purpose

During acute coronavirus disease 2019 (COVID‐19) infection, neurological signs, symptoms and complications occur. We aimed to assess their clinical relevance by evaluating real‐world data from a multinational registry.

Methods

We analyzed COVID‐19 patients from 127 centers, diagnosed between January 2020 and February 2021, and registered in the European multinational LEOSS (Lean European Open Survey on SARS‐Infected Patients) registry. The effects of prior neurological diseases and the effect of neurological symptoms on outcome were studied using multivariate logistic regression.

Results

A total of 6537 COVID‐19 patients (97.7% PCR‐confirmed) were analyzed, of whom 92.1% were hospitalized and 14.7% died. Commonly, excessive tiredness (28.0%), headache (18.5%), nausea/emesis (16.6%), muscular weakness (17.0%), impaired sense of smell (9.0%) and taste (12.8%), and delirium (6.7%) were reported. In patients with a complicated or critical disease course (53%) the most frequent neurological complications were ischemic stroke (1.0%) and intracerebral bleeding (ICB; 2.2%). ICB peaked in the critical disease phase (5%) and was associated with the administration of anticoagulation and extracorporeal membrane oxygenation (ECMO). Excessive tiredness (odds ratio [OR] 1.42, 95% confidence interval [CI] 1.20–1.68) and prior neurodegenerative diseases (OR 1.32, 95% CI 1.07–1.63) were associated with an increased risk of an unfavorable outcome. Prior cerebrovascular and neuroimmunological diseases were not associated with an unfavorable short‐term outcome of COVID‐19.

Conclusion

Our data on mostly hospitalized COVID‐19 patients show that excessive tiredness or prior neurodegenerative disease at first presentation increase the risk of an unfavorable short‐term outcome. ICB in critical COVID‐19 was associated with therapeutic interventions, such as anticoagulation and ECMO, and thus may be an indirect complication of a life‐threatening systemic viral infection.

COVID-19 Associated Coagulopathy in an Indian Scenario: A Correlation with Disease Severity and Survival Status

Covid-19 pandemic reveals that the virus causes Covid-19 associated coagulopathy and it is well known that thrombotic risk is associated with ethnicity. To describe the Covid-19 associated coagulopathy in Indian population and to correlate it with the disease severity and survivor status. A cross sectional descriptive study of 391 confirmed Covid-19 cases was carried out over a period of 1.5 months. Patients were categorised as mild to moderate, severe and very severe and also labelled as survivors and non survivors. Prothrombin time (PT), International normalised ratio (INR), activated partial thromboplastin time, D dimer, Fibrin degradation products (FDP), fibrinogen and thrombin time and platelet counts were investigated among the subgroups. Mean age was higher in patients with severe disease (57.62 ± 13.08) and among the non survivors (56.54 ± 12.78). Statistically significant differences in D dimer, FDP, PT, INR and age were seen among the 3 subgroups and survivors. Strong significant positive correlation was noted between D dimer and FDP (r = 0.838, p < .001), PT and INR (r = 0.986, p < 0.001). D dimer was the best single coagulation parameter as per the area under curve (AUC: 0.762, p < 0.001) and D dimer + FDP was the best combination parameter (AUC: 0.764, p = 0) to differentiate mild moderate from severe disease. Raised levels of D dimer, FDP, PT, PT INR and higher age correlated positively with disease severity and mortality in Indian Population.