Clinical features of thrombosis and bleeding in COVID-19

Impact of COVID-19 pandemic on acute stroke care in a tertiary stroke centre

The aim of this study was to evaluate how COVID-19 affected acute stroke care and outcome in patients with acute ischemic or hemorrhagic stroke. We performed a retrospective analysis on patients who were admitted with acute ischemic (AIS) or hemorrhagic (ICH) stroke from September 2020 to May 2021 with and without COVID-19. We recorded demographic and clinical data, imaging parameters, functional outcome and mortality at one year. Beside descriptive statistics we performed χ2-probe, Mann-Witney U-test, Student t-probe and multivariate testing. We found a 29%-reduction in the number of AIS cases during the pandemic. The number of the large vessel occlusions /LVOs/ (N = 83, 41.7%), from them 37 (17.7%) had mechanical thrombectomy (MT), was higher than before the COVID-19 period (p = 0.02 and p = 0.001, respectively). From all patients needing acute revascularization therapy (N = 137) 118 patients received it, among them 20 (16.9%) had COVID-19. Those positive for COVID-19 were more likely to have a higher median NIHSS score at baseline and at 24 h (p = 0.02 and p = 0.03, respectively). They also had a lower rate of favourable outcome at discharge (15% vs. 41.8%; p = 0.024) and at three months (25% vs. 52%, p = 0.02), longer median hospitalization (p < 0.0001), and a higher mortality rate (52% vs. 25%; p = 0.03). The incidence of symptomatic intracerebral hemorrhage (sICH) did not differ between the groups. Regarding the ICH patients, NIHSS score at 24 h (p = 0.036), mortality at 3 months (p = 0.004) and at one year (p = 0.00) were higher in the COVID-19 group. We concluded that the pandemic resulted fewer admission due to AIS with an increased number of LVOs and MTs. AIS patients with concomitant SARS-CoV-2 infection have more severe strokes and unfavorable long term outcome. The risk of sICH was not increased in COVID-19 positive patients therefore reperfusion therapies appear to be safe and beneficial for some individuals. Patients with ICH and comorbid COVID-19 have a very poor prognosis.

Thrombotic Long-Term Consequences of SARS-CoV-2 Infection in Patients with Compensated Cirrhosis: A Propensity Score-Matched Analysis of a U.S. Database

BACKGROUND

Cirrhosis causes an imbalance in the coagulation pathway and leads to a tendency for both bleeding and clotting. SARS-CoV-2 has been reported to be associated with a hypercoagulable state. This study examines SARS-CoV-2's impact on hemostasis in compensated patients with cirrhosis.

METHODS

We analyzed the US Collaborative Network, which comprises 63 HCOs in the U.S.A. Compensated cirrhosis patients were split into two groups: SARS-CoV-2-positive and -negative. Patients' baseline characteristics were used in a 1:1 propensity score-matched module to create comparable cohorts. We compared the risk of portal vein thrombosis (PVT), deep venous thrombosis (DVT), and pulmonary embolism (PE) at 6 months, and 1 and 3 years.

RESULTS

Of 330,521 patients, 27% tested positive and 73% remained negative. After PSM, both cohorts included 74,738 patients. Patients with SARS-CoV-2 had a higher rate of PVT compared to those without at 6 months (0.63% vs 0.5%, p < 0.05), 1 year (0.8% vs 0.6%, p < 0.05), and 3 years (1% vs. 0.7%, p < 0.05), a higher rate of DVT at 6 months (0.8% vs. 0.4%, p < 0.05), 1 year (1% vs. 0.5%, p < 0.05), and 3 years (1.4% vs. 0.8%, p < 0.05), and a higher rate of PE at 6 months (0.6% vs. 0.3%, p < 0.05), 1 year (0.7% vs. 0.4%, p < 0.05), and 3 years (1% vs. 0.6%, p < 0.05).

CONCLUSIONS

The presence of SARS-CoV-2 infection in patients with compensated cirrhosis was associated with a higher rate of PVT, DVT, and PE at 6 months, and 1 and 3 years.

Subacute Limb Ischemia Suspected from COVID-19-Related Arterial Thrombosis Presenting with Local Occlusion Site Tenderness

A 59-year-old man was admitted to our hospital with severe popliteal fossa pain and mild left calf claudication. He had had an episode of pyrexia and dyspnea approximately 3 weeks prior. Contrast-enhanced computed tomography revealed acute occlusion of the left popliteal artery and multiple infiltration shadows with bilateral multifocal parenchymal consolidation of the lungs, suggesting post-coronavirus disease 2019 (COVID-19) pneumonia. As he had no comorbid risk of cardiogenic embolism or atherosclerosis, we diagnosed him with COVID-19-related arterial thrombosis. COVID-19-related arterial thrombosis should be considered a possible cause of acute limb ischemia, even when ischemic symptoms occur several weeks post infection.

Effects of the Omicron variant of coronavirus disease 2019 on anaemia treatment for patients undergoing peritoneal dialysis

AIM

Patients undergoing dialysis are at high risk for coronavirus disease 2019 (COVID-19). Haemoglobin (Hb) levels may be changed in patients infected with the Omicron variant of COVID-19 who are undergoing peritoneal dialysis (PD). Therefore, we aimed to explore the effect of anti-anaemia treatment on such patients.

METHODS

This study enrolled patients undergoing PD who were infected with the Omicron variant of COVID-19 at our centre between November 2022 and February 2023. We retrospectively analysed changes in Hb levels and explored the effectiveness of roxadustat and recombinant human erythropoietin (rhEPO) for patients infected with the Omicron variant of COVID-19.

RESULTS

Among 125 enrolled patients, 83 (66.4%) were infected with the Omicron variant and 75 (90.4%) patients mainly experienced mild or moderate disease. During infection, C-reactive protein (CRP) levels were higher than those before infection (p < .001). Additionally, their CRP levels were negatively correlated with Hb levels (p = .002). However, Hb levels were decreased 1 month after infection (109.61 ± 10.64 g/L vs. 115.69 ± 12.04 g/L; p < .001). The roxadustat treatment group did not exhibit significantly decreased Hb levels 1 month after infection (114.57 ± 14.11 vs. 117.51 ± 10.74 g/L; p = .225). Conversely, the rhEPO treatment group experienced a mild decrease in Hb levels (108.69 ± 11.20 vs. 115.03 ± 12.23 g/L; p = .001). Ferritin levels increased in both groups during infection (p = .495). Two months after infection, ferritin levels (median, 205.0 ng/mL) were significantly decreased compared with during infection (median, 377.4 ng/mL) (p < .001) in the roxadustat treatment group.

CONCLUSION

Roxadustat was effective than rhEPO for treating anaemia in patients undergoing PD who were infected with the Omicron variant of COVID-19.

Prevention of Venous Thromboembolism in Medical Patients with Thrombocytopenia or with Platelet Dysfunction: The Last 10 Years

Current guideline recommendations for primary prophylaxis of venous thromboembolism (VTE) are based on randomized clinical trials that usually exclude subjects at a potentially high risk of bleeding complications. For this reason, no specific guideline is available for thromboprophylaxis in hospitalized patients with thrombocytopenia and/or platelet dysfunction. However, except in patients with absolute contraindications to anticoagulant drugs, antithrombotic prophylaxis should always be considered, for example, in hospitalized cancer patients with thrombocytopenia, especially in those with multiple VTE risk factors. Low platelet number, platelet dysfunction, and clotting abnormalities are also very common in patients with liver cirrhosis, but these patients have a high incidence of portal venous thrombosis, implying that cirrhotic coagulopathy does not fully protect against thrombosis. These patients may benefit from antithrombotic prophylaxis during hospitalization. Patients hospitalized for COVID-19 need prophylaxis, but frequently experience thrombocytopenia or coagulopathy. In patients with antiphospholipid antibodies, a high thrombotic risk is usually present, even in the presence of thrombocytopenia. VTE prophylaxis in high-risk conditions is thus suggested in these patients. At variance with severe thrombocytopenia (< 50,000/mm3), mild/moderate thrombocytopenia (≥ 50,000/mm3) should not interfere with VTE prevention decisions. In patients with severe thrombocytopenia, pharmacological prophylaxis should be considered on an individual basis. Aspirin is not as effective as heparins in lowering the risk of VTE. Studies in patients with ischemic stroke demonstrated that thromboprophylaxis with heparins is safe in these patients also during antiplatelet treatment. The use of direct oral anticoagulants in the prophylaxis of VTE in internal medicine patients has been recently evaluated, but no specific recommendation exists for patients with thrombocytopenia. The need for VTE prophylaxis in patients on chronic treatment with antiplatelet agents should be evaluated after assessing the individual risk of bleeding complications. Finally, the selection of patients who require post-discharge pharmacological prophylaxis remains debated. New molecules currently under development (such as the inhibitors of factor XI) may contribute to improve the risk/benefit ratio of VTE primary prevention in this setting of patients.

Damage to endothelial barriers and its contribution to long COVID

The world continues to contend with COVID-19, fueled by the emergence of viral variants. At the same time, a subset of convalescent individuals continues to experience persistent and prolonged sequelae, known as long COVID. Clinical, autopsy, animal and in vitro studies all reveal endothelial injury in acute COVID-19 and convalescent patients. Endothelial dysfunction is now recognized as a central factor in COVID-19 progression and long COVID development. Different organs contain different types of endothelia, each with specific features, forming different endothelial barriers and executing different physiological functions. Endothelial injury results in contraction of cell margins (increased permeability), shedding of glycocalyx, extension of phosphatidylserine-rich filopods, and barrier damage. During acute SARS-CoV-2 infection, damaged endothelial cells promote diffuse microthrombi and destroy the endothelial (including blood-air, blood-brain, glomerular filtration and intestinal-blood) barriers, leading to multiple organ dysfunction. During the convalescence period, a subset of patients is unable to fully recover due to persistent endothelial dysfunction, contributing to long COVID. There is still an important knowledge gap between endothelial barrier damage in different organs and COVID-19 sequelae. In this article, we mainly focus on these endothelial barriers and their contribution to long COVID.

Infectious Diseases

Microglia, brain-resident innate immune cells, have been extensively studied in neurodegenerative contexts like Alzheimer's disease. The Coronavirus disease 2019 (COVID-19) pandemic highlighted how peripheral infection and inflammation can be detrimental to the neuroimmune milieu and initiate microgliosis driven by peripheral inflammation. Microglia can remain deleterious to brain health by sustaining inflammation in the central nervous system even after the clearance of the original immunogenic agents. In this chapter, we discuss how pulmonary infection with Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2) can lead to neurovascular and neuroimmune inflammation causing the neurological syndrome of post-acute sequelae of COVID-19 (PASC). Further, we incorporate lessons from the Human Immunodeficiency Virus' (HIV's) effects on microglial functioning in the era of combined antiretroviral therapies (cART) that contribute to HIV-1 associated neurocognitive disorders (HAND). Finally, we describe roles for mixed lineage kinase 3 (MLK3) and leucine-rich repeat kinase (LRRK2) as key regulators of multiple inflammatory and apoptotic pathways important to the pathogenesis of PASC and HAND. Inhibition of these pathways provides a therapeutically synergistic method of treating both PASC and HAND.

Genetic and immunological insights into COVID-19 with acute myocardial infarction: integrated analysis of mendelian randomization, transcriptomics, and clinical samples

Background

Globally, most deaths result from cardiovascular diseases, particularly ischemic heart disease. COVID-19 affects the heart, worsening existing heart conditions and causing myocardial injury. The mechanistic link between COVID-19 and acute myocardial infarction (AMI) is still being investigated to elucidate the underlying molecular perspectives.

Methods

Genetic risk assessment was conducted using two-sample Mendelian randomization (TSMR) to determine the causality between COVID-19 and AMI. Weighted gene co-expression network analysis (WGCNA) and machine learning were used to discover and validate shared hub genes for the two diseases using bulk RNA sequencing (RNA-seq) datasets. Additionally, gene set enrichment analysis (GSEA) and single-cell RNA-seq (scRNA-seq) analyses were performed to characterize immune cell infiltration, communication, and immune correlation of the hub genes. To validate the findings, the expression patterns of hub genes were confirmed in clinical blood samples collected from COVID-19 patients with AMI.

Results

TSMR did not find evidence supporting a causal association between COVID-19 or severe COVID-19 and AMI. In the bulk RNA-seq discovery cohorts for both COVID-19 and AMI, WGCNA's intersection analysis and machine learning identified TLR4 and ABCA1 as significant hub genes, demonstrating high diagnostic and predictive value in the RNA-seq validation cohort. Single-gene GSEA and single-sample GSEA (ssGSEA) revealed immune and inflammatory roles for TLR4 and ABCA1, linked to various immune cell infiltrations. Furthermore, scRNA-seq analysis unveiled significant immune dysregulation in COVID-19 patients, characterized by altered immune cell proportions, phenotypic shifts, enhanced cell-cell communication, and elevated TLR4 and ABCA1 in CD16 monocytes. Lastly, the increased expression of TLR4, but not ABCA1, was validated in clinical blood samples from COVID-19 patients with AMI.

Conclusion

No genetic causal link between COVID-19 and AMI and dysregulated TLR4 and ABCA1 may be responsible for the development of immune and inflammatory responses in COVID-19 patients with AMI.

COVID-19 Associated Micro-Anastomotic Thrombosis After Abdominal Free Tissue Transfer: A Case Report and Literature Review

The hypercoagulable state of COVID-19 infection presents a challenge to microsurgeons. While the American Society of Anesthesiologists recommends deferring surgery for 4-10 weeks for COVID-19-infected patients, little else is known regarding how to mitigate thrombotic complications for patients undergoing free tissue transfer. Here, we present a presumed COVID-19-induced hypercoagulable state in a patient undergoing abdominally based free tissue transfer for breast reconstruction as a brief review of the literature to guide clinical decision making.

Utility of pre-chemoradiotherapy Pan-Immune-Inflammation-Value for predicting the osteoradionecrosis rates in locally advanced nasopharyngeal cancers

PURPOSE

The aim of this retrospective study was to explore whether pretreatment Pan-Immune-Inflammation-Value (PIV) measurements might predict the risk of mandibular osteoradionecrosis (ORN) in patients receiving concurrent chemoradiotherapy (CCRT) for locally advanced nasopharyngeal cancer (LA-NPC).

METHODS

The platelet, monocyte, neutrophil, and lymphocyte counts acquired on the first day of CCRT were used to compute pretreatment PIV levels: PIV = (Platelets × Monocytes × Neutrophils) ÷ Lymphocytes. Receiver operating characteristic curve analysis was used to determine the association between ORN rates and PIV levels. Spearman correlation analysis was used to examine the probable intergroup correlations. The potential link between the pretreatment PIV levels and the post-treatment ORN rates was determined as the primary objective.

RESULTS

21 (10.0%) of 210 eligible patients were diagnosed with ORN. The optimal pre-CCRT PIV cutoff was 833, which separated patients into two PIV groups with divergent ORN prevalence estimates: Group 1: PIV < 833 (N = 153), and Group 2: PIV ≥ 833 (N = 57). The comparison analysis found that the PIV ≥ 833 cohort had significantly higher ORN rates than the PIV < 833 cohort (29.8% vs. 2.6%; P < 0.001). Other characteristics linked to significantly higher ORN rates were the patient's continuing smoking, the use of the Three-dimensional conformal radiation therapy technique, the mean mandibular dose of ≥ 58.1 Gy, the number of tooth extractions before CCRT ≥ 4, and the presence of tooth extractions after CCRT. The independent importance of all factors on higher ORN occurrence rates were retained in multivariate analysis (P < 0.05).

CONCLUSIONS

Our findings revealed a strong link between aggravated inflammatory response and ORN genesis, with high pretreatment PIV levels related to significantly higher ORN rates.

Thombosis, major bleeding, and survival in COVID-19 supported by veno-venous extracorporeal membrane oxygenation in the first vs second wave: a multicenter observational study in the United Kingdom

BACKGROUND

Bleeding and thrombosis are major complications of veno-venous (VV) extracorporeal membrane oxygenation (ECMO).

OBJECTIVES

To assess thrombosis, major bleeding (MB), and 180-day survival in patients supported by VV-ECMO between the first (March 1 to May 31, 2020) and second (June 1, 2020, to June 30, 2021) waves of the COVID-19 pandemic.

METHODS

An observational study of 309 consecutive patients (aged ≥18years) with severe COVID-19 supported by VV-ECMO was performed in 4 nationally commissioned ECMO centers in the United Kingdom.

RESULTS

Median age was 48 (19-75) years, and 70.6% were male. Probabilities of survival, thrombosis, and MB at 180 days in the overall cohort were 62.5% (193/309), 39.8% (123/309), and 30% (93/309), respectively. In multivariate analysis, an age of >55 years (hazard ratio [HR], 2.29; 95% CI, 1.33-3.93; P = .003) and an elevated creatinine level (HR, 1.91; 95% CI, 1.19-3.08; P = .008) were associated with increased mortality. Correction for duration of VV-ECMO support, arterial thrombosis alone (HR, 3.0; 95% CI, 1.5-5.9; P = .002) or circuit thrombosis alone (HR, 3.9; 95% CI, 2.4-6.3; P < .001) but not venous thrombosis increased mortality. MB during ECMO had a 3-fold risk (95% CI, 2.6-5.8, P < .001) of mortality. The first wave cohort had more males (76.7% vs 64%; P = .014), higher 180-day survival (71.1% vs 53.3%; P = .003), more venous thrombosis alone (46.4% vs 29.2%; P = .02), and lower circuit thrombosis (9.2% vs 28.1%; P < .001). The second wave cohort received more steroids (121/150 [80.6%] vs 86/159 [54.1%]; P < .0001) and tocilizumab (20/150 [13.3%] vs 4/159 [2.5%]; P = .005).

CONCLUSION

MB and thrombosis are frequent complications in patients on VV-ECMO and significantly increase mortality. Arterial thrombosis alone or circuit thrombosis alone increased mortality, while venous thrombosis alone had no effect. MB during ECMO support increased mortality by 3.9-fold.

Investigation of Cognitive Impairment in the Course of Post-COVID Syndrome

(1) Background: The study presents results from an investigation of cognitive impairment in patients hospitalized in the first psychiatric clinic in Bulgaria to treat patients with COVID-19 during the pandemic period between 2020 and 2022. One hundred and twenty patients who had recovered from acute COVID-19 infection (up to 12 weeks ago) and had no previous history of cognitive impairment participated in the study. In 23 of them (19.17%), disturbance of cognitive functioning was observed. (2) Methods: All 23 patients underwent neuropsychological (Luria's test, Platonov's Maze test, MMSE, Boston Naming test) and neuroimaging examinations. Only seven of them had evidence of cortical atrophy on CT/MRI images. The most significantly demonstrative image of one of those patients is presented. (3) Results: The neuropsychological testing results of both groups show a certain decrease in fixation and memory retention as well as in the range, concentration, distribution and switching of attention. Deviations from the norm on the MMSE, as well as on the Boston Naming Test, were found in the group of patients with cortical atrophy (mild to moderate aphasia). Neuroprotective agents such as Citicoline, Piracetam and Memantine were prescribed to the patients with evident cortical atrophy. After 3 months, positive results of the neuropsychological examination were reported in both groups. (4) Conclusions: Although there are limited data on the benefit of prescribing pro-cognitive agents in the post-COVID period, our clinical experience suggests that it might be useful in the recovery process from the infection's consequences on cognition for patients with brain pathology.

Incidence, Risk Factors and Mortality Associated with Major Bleeding Events in Hospitalized COVID-19 Patients

Thromboprophylaxis is a mainstay of treatment of hospitalized COVID-19 patients, due to the high occurrence of thrombotic events. This increases the risk of bleeding. However, data on bleeding events and associated risk factors are scarce. Thus, we aimed to investigate the incidence, predictors and clinical outcomes associated with major bleeding in hospitalized COVID-19 patients. We retrospectively evaluated a cohort of 4014 consecutively hospitalized COVID-19 patients treated in a tertiary-level institution in the period 3/2020-3/2021. Bleeding of any kind was documented in 322 (8%) and major bleeding in 129 (3.2%) patients. A total of 129 (40.1%) bleeding events were present at the time of hospital admission, and 193 (59.9%) occurred during hospitalization. In the multivariate logistic regression analysis, intensive-care-unit treatment (adjusted odds ratio (aOR) 6.55; p < 0.001), atrial fibrillation (aOR 2.55; p = 0.029), higher white-blood-cell count (WBC) (aOR 1.03; p = 0.021), lower hemoglobin (aOR 0.97; p = 0.002) and history of bleeding (aOR 17.39; p < 0.001) were recognized as mutually independent predictors of major bleeding. Major bleeding was significantly associated with increased in-hospital mortality compared to non-major-bleeding patients (59.7% vs. 34.8%, p < 0.001), especially if occurring during hospitalization. Median time from major bleeding to death was 5 days. Bleeding events are frequent in hospitalized COVID-19 patients, with a significant proportion of patients presenting at the time of hospital admission, and others almost universally exposed to anticoagulant and corticosteroid therapies. Major bleeding is associated with high mortality, especially if occurring during hospitalization. The recognition of patients at risk and implementation of timely interventions are of high clinical importance.

In Situ Pulmonary Arterial Thrombosis: Literature Review and Clinical Significance of a Distinct Entity

Filling defects identified in the pulmonary arterial tree are commonly presumed to represent an embolic phenomenon originating from thrombi formed in remote veins, particularly lower-extremity deep venous thrombosis (DVT). However, accumulating evidence supports an underappreciated cause for pulmonary arterial thrombosis (PAT), namely, de novo thrombogenesis-whereby thrombosis arises within the pulmonary arteries in the absence of DVT. Although historically underrecognized, in situ PAT has become of heightened importance with the emergence of SARS-CoV-2 infection. In situ PAT is attributed to endothelial dysfunction, systemic inflammation, and acute lung injury and has been described in a range of conditions including COVID-19, trauma, acute chest syndrome in sickle cell disease, pulmonary infections, and severe pulmonary arterial hypertension. The distinction between pulmonary embolism and in situ PAT may have important implications regarding management decisions and clinical outcomes. In this review, we summarize the pathophysiology, imaging appearances, and management of in situ PAT in various clinical situations. This understanding will promote optimal tailored treatment strategies for this increasingly recognized entity.

Integral assays of hemostasis in hospitalized patients with COVID-19 on admission and during heparin thromboprophylaxis

BACKGROUND

Blood coagulation abnormalities play a major role in COVID-19 pathophysiology. However, the specific details of hypercoagulation and anticoagulation treatment require investigation. The aim of this study was to investigate the status of the coagulation system by means of integral and local clotting assays in COVID-19 patients on admission to the hospital and in hospitalized COVID-19 patients receiving heparin thromboprophylaxis.

METHODS

Thrombodynamics (TD), thromboelastography (TEG), and standard clotting assays were performed in 153 COVID-19 patients observed in a hospital setting. All patients receiving treatment, except extracorporeal membrane oxygenation (ECMO) patients (n = 108), were administered therapeutic doses of low molecular weight heparin (LMWH) depending on body weight. The ECMO patients (n = 15) were administered unfractionated heparin (UFH).

RESULTS

On admission, the patients (n = 30) had extreme hypercoagulation by all integral assays: TD showed hypercoagulation in ~75% of patients, while TEG showed hypercoagulation in ~50% of patients. The patients receiving treatment showed a significant heparin response based on TD; 77% of measurements were in the hypocoagulation range, 15% were normal, and 8% remained in hypercoagulation. TEG showed less of a response to heparin: 24% of measurements were in the hypocoagulation range, 59% were normal and 17% remained in hypercoagulation. While hypocoagulation is likely due to heparin treatment, remaining in significant hypercoagulation may indicate insufficient anticoagulation for some patients, which is in agreement with our clinical findings. There were 3 study patients with registered thrombosis episodes, and all were outside the target range for TD parameters typical for effective thromboprophylaxis (1 patient was in weak hypocoagulation, atypical for the LMWH dose used, and 2 patients remained in the hypercoagulation range despite therapeutic LMWH doses).

CONCLUSION

Patients with COVID-19 have severe hypercoagulation, which persists in some patients receiving anticoagulation treatment, while significant hypocoagulation is observed in others. The data suggest critical issues of hemostasis balance in these patients and indicate the potential importance of integral assays in its control.

An Evolving Understanding of the Basis and Management of Vascular Complications of COVID-19: Where Do We Go From Here?

The COVID-19 pandemic led to millions of deaths worldwide after its emergence in 2020. The SARS-CoV-2 virus primarily affects respiratory function, but immune dysregulation leading to systemic inflammation, endothelial dysfunction, and coagulopathy can predispose to systemic complications including hematologic and vascular complications. Treatment strategies for patients with COVID-19 have rapidly evolved and the effectiveness and safety of antithrombotic agents have been evaluated in multiple clinical trials. The findings have spurred interest in the prevention and treatment of the hematologic and vascular complications of non-COVID-19 respiratory infections. This review is focused on hematological and vascular complications of COVID-19, including their pathophysiology, clinical manifestations, and management. Because of the perpetually changing nature of the disease, the review places previous data in temporal contexts and outlines potential next steps for future research in COVID-19 and other severe respiratory infections.

A Zebra Diagnosis: A Case of Spontaneous Hematomyelia Associated With COVID-19

Spontaneous non-traumatic spinal hematomyelia, characterized by intramedullary spinal hematoma, is a rare neurological emergency. Bleeding arteriovenous malformation, coagulopathies, and neoplasms are reported causes of this rare diagnosis. The authors present a case of a previously healthy man who presented with acute paraplegia and was found to have a spontaneous hematomyelia in association with covid infection. He underwent laminectomy and hematoma evacuation but did not recover any neurological function.

Clinical characteristics of COVID-19 associated vasculopathic diseases

Coronavirus disease 19 (COVID-19) has shown to be an infectious disease affecting not only of the respiratory system, but also cardiovascular system leading to different COVID-19-associated vasculopathies. Venous and arterial thromboembolic events have been frequently described among hospitalized patients with COVID-19 and inflammatory vasculopathic changes have also been observed. Several of the reported COVID-19 associated vasculopathies exhibit differences on epidemiology, clinical characteristics and outcome compared to non-COVID-19 types. This review focuses on the epidemiology, clinical, diagnostic and therapeutic characteristics as well as outcome data of COVID-19 associated thromboembolic events and inflammatory vasculopathies, elaborating similarities and differences with non-COVID-19 cohorts.

Effects of 12 mg vs. 6 mg dexamethasone on thromboembolism and bleeding in patients with critical COVID-19 - a post hoc analysis of the randomized, blinded COVID STEROID 2 trial

BACKGROUND

Thromboembolism is more common in patients with critical COVID-19 than in other critically ill patients, and inflammation has been proposed as a possible mechanism. The aim of this study was to investigate if 12 mg vs. 6 mg dexamethasone daily reduced the composite outcome of death or thromboembolism in patients with critical COVID-19.

METHODS

Using additional data on thromboembolism and bleeding we did a post hoc analysis of Swedish and Danish intensive care unit patients enrolled in the blinded randomized COVID STEROID 2 trial comparing 12 mg vs. 6 mg dexamethasone daily for up to 10 days. The primary outcome was a composite outcome of death or thromboembolism during intensive care. Secondary outcomes were thromboembolism, major bleeding, and any bleeding during intensive care.

RESULTS

We included 357 patients. Whilst in intensive care, 53 patients (29%) in the 12 mg group and 53 patients (30%) in the 6 mg group met the primary outcome with an unadjusted absolute risk difference of - 0.5% (95% CI - 10 to 9.5%, p = 1.00) and an adjusted OR of 0.93 (CI 95% 0.58 to 1.49, p = 0.77). We found no firm evidence of differences in any of the secondary outcomes.

CONCLUSIONS

Among patients with critical COVID-19, 12 mg vs. 6 mg dexamethasone daily did not result in a statistically significant difference in the composite outcome of death or thromboembolism. However, uncertainty remains due to the limited number of patients.

An Integrated Radiologic-Pathologic Understanding of COVID-19 Pneumonia

This article reviews the radiologic and pathologic findings of the epithelial and endothelial injuries in COVID-19 pneumonia to help radiologists understand the fundamental nature of the disease. The radiologic and pathologic manifestations of COVID-19 pneumonia result from epithelial and endothelial injuries based on viral toxicity and immunopathologic effects. The pathologic features of mild and reversible COVID-19 pneumonia involve nonspecific pneumonia or an organizing pneumonia pattern, while the pathologic features of potentially fatal and irreversible COVID-19 pneumonia are characterized by diffuse alveolar damage followed by fibrosis or acute fibrinous organizing pneumonia. These pathologic responses of epithelial injuries observed in COVID-19 pneumonia are not specific to SARS-CoV-2 but rather constitute universal responses to viral pneumonia. Endothelial injury in COVID-19 pneumonia is a prominent feature compared with other types of viral pneumonia and encompasses various vascular abnormalities at different levels, including pulmonary thromboembolism, vascular engorgement, peripheral vascular reduction, a vascular tree-in-bud pattern, and lung perfusion abnormality. Chest CT with different imaging techniques (eg, CT quantification, dual-energy CT perfusion) can fully capture the various manifestations of epithelial and endothelial injuries. CT can thus aid in establishing prognosis and identifying patients at risk for deterioration.

Time series analysis revealed prognostic value of continuous nasopharyngeal SARS-CoV-2 nucleic acid quantification for COVID-19: A retrospective study of >3000 COVID-19 patients from 2 centers

BACKGROUND

Early stratification of disease progression remains one of the major challenges towards the post-coronavirus disease 2019 (COVID-19) era. The clinical relevance of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid load is debated due to the heterogeneity in patients' underlying health conditions. We determined the prognostic value of nasopharyngeal viral load dynamic conversion for COVID-19.

METHODS

The cycling threshold (Ct) values of 28,937 nasopharyngeal SARS-CoV-2 RT-PCRs were retrospectively collected from 3,364 COVID-19 patients during hospitalization and coordinated to the onset of disease progression. The ROC curve was utilized to determine the predictive performance of the rate of Ct value alteration between two consecutive RT-PCR runs within 48 h (ΔCt%) for disease transformation across patients with different COVID-19 severity and immune backgrounds, and further validated with 1,860 SARS-CoV-2 RT-PCR results from an independent validation cohort of 262 patients. For the 67 patients with severe COVID-19, Kaplan-Meier analysis was performed to evaluate the difference in survival between patients stratified by the magnitude of Ct value alteration between the late and early stages of hospitalization.

RESULTS

The kinetics of viral nucleic acid conversion diversified across COVID-19 patients with different clinical characteristics and disease severities. The ΔCt% is a clinical characteristic- and host immune status-independent indicator for COVID-19 progression prediction (AUC = 0.79, 95 % CI = 0.76 to 0.81), which outperformed the canonical blood test markers, including c-reactive protein (AUC = 0.57, 95 % CI = 0.53 to 0.61), serum amyloid A (AUC = 0.61, 95 % CI = 0.54 to 0.68), lactate dehydrogenase (AUC = 0.61, 95 % CI = 0.56 to 0.67), d-dimer (AUC = 0.56, 95 % CI = 0.46 to 0.66), and lymphocyte count (AUC = 0.62, 95 % CI = 0.58 to 0.66). Patients with persistent high SARS-CoV-2 viral load (an increase of mean Ct value < 50 %) during the first 3 days of hospitalization demonstrated a significantly unfavorable survival (HR = 0.16, 95 % CI = 0.04 to 0.65, P = 2.41 × 10^-3).

CONCLUSIONS

Viral nucleic acid dynamics of SARS-CoV-2 eliminates the inter-patient variance of basic health conditions and therefore, can serve as a prognostic marker for COVID-19.

Omicron, Long-COVID, and the Safety of Elective Surgery for Adults and Children: Joint Guidance from the Therapeutics and Guidelines Committee of the Surgical Infection Society and the Surgery Strategic Clinical Network, Alberta Health Services

Background: Active and recent coronavirus disease 2019 (COVID-19) infections are associated with morbidity and mortality after surgery in adults. Current recommendations suggest delaying elective surgery in survivors for four to 12 weeks, depending on initial illness severity. Recently, the predominant causes of COVID-19 are the highly transmissible/less virulent Omicron variant/subvariants. Moreover, increased survivability of primary infections has engendered the long-COVID syndrome, with protean manifestations that may persist for months. Considering the more than 600,000,000 COVID-19 survivors, surgeons will likely be consulted by recovered patients seeking elective operations. Knowledge gaps of the aftermath of Omicron infections raise questions whether extant guidance for timing of surgery still applies to adults or should apply to the pediatric population. Methods: Scoping review of relevant English-language literature. Results: Most supporting data derive from early in the pandemic when the Alpha variant of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) predominated. The Omicron variant/subvariants generally cause milder infections with less organ dysfunction; many infections are asymptomatic, especially in children. Data are scant with respect to adult surgical outcomes after Omicron infection, and especially so for pediatric surgical outcomes at any stage of the pandemic. Conclusions: Numerous knowledge gaps persist with respect to the disease, the recovered pre-operative patient, the nature of the proposed procedure, and supporting data. For example, should the waiting period for all but urgent elective surgery be extended beyond 12 weeks, e.g., after serious/critical illness, or for patients with long-COVID and organ dysfunction? Conversely, can the waiting periods for asymptomatic patients or vaccinated patients be shortened? How shall children be risk-stratified, considering the distinctiveness of pediatric COVID-19 and the paucity of data? Forthcoming guidelines will hopefully answer these questions but may require ongoing modifications based on additional new data and the epidemiology of emerging strains.

Evaluation of a fast-and-frugal clinical decision algorithm ('pathways') on clinical outcomes in hospitalised patients with COVID-19 treated with anticoagulants

RATIONALE, AIMS AND OBJECTIVES

Critics have charged that evidence-based medicine (EBM) overemphasises algorithmic rules over unstructured clinical experience and intuition, but the role of structured decision support systems in improving health outcomes remains uncertain. We aim to assess if delivery of anticoagulant prophylaxis in hospitalised patients with COVID-19 according to an algorithm based on evidence-based clinical practice guideline (CPG) improved clinical outcomes compared with administration of anticoagulant treatment given at individual practitioners' discretion.

METHODS

An observational design consisting of the analysis of all acutely ill, consecutive patients (n = 1783) with confirmed COVID-19 diagnosis admitted between 10 March 2020 to 11 January 2022 to an US academic center. American Society of Haematology CPG for anticoagulant prophylaxis in hospitalised patients with COVID-19 was converted into a clinical pathway and translated into fast-and-frugal decision (FFT) tree ('algorithm'). We compared delivery of anticoagulant prophylaxis in hospitalised patients with COVID-19 according to the FFT algorithm with administration of anticoagulant treatment given at individual practitioners' discretion.

RESULTS

In an adjusted analysis, using combination of Lasso (least absolute shrinkage and selection operator) and propensity score based weighting [augmented inverse-probability weighting] statistical techniques controlling for cluster data, the algorithm did not reduce death, venous thromboembolism, or major bleeding, but helped avoid longer hospital stay [number of patients needed to be treated (NNT) = 40 (95% CI: 23-143), indicating that for every 40 patients (23-143) managed on FFT algorithm, one avoided staying in hospital longer than 10 days] and averted admission to intensive-care unit (ICU) [NNT = 19 (95% CI: 13-40)]. All model's selected covariates were well balanced. The results remained robust to sensitivity analyses used to test the stability of the findings.

CONCLUSIONS

When delivered using a structured FFT algorithm, CPG shortened the hospital stay and help avoided admission to ICU, but it did not affect other relevant outcomes.

A Review of Coronavirus Disease 2019 in Pregnancy

Pregnancy is an independent risk factor for morbidity and mortality in coronavirus disease 2019 (COVID-19) with increased rates of operative delivery, intensive care unit admission, and mechanical ventilation as well as a possible increased risk of death, independent of other risk factors, compared with nonpregnant women with COVID-19. Furthermore, pregnancy outcomes are worse in those with COVID-19 with increased risk for preeclampsia, venous thromboembolism, preterm birth, miscarriage, and stillbirth compared with pregnant women without COVID-19. Importantly, pregnant women of nonwhite ethnicity appear to be at greater risk of severe COVID-19, necessitating improved access to care and closer monitoring in these women. The management of COVID-19 in pregnancy is largely similar to that in nonpregnant people; however, there is an important emphasis on multidisciplinary team involvement to ensure favorable outcomes in both mother and baby. Similarly, vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is safe in pregnancy and improves maternal and neonatal outcomes.

The Role of the Plasminogen/Plasmin System in Inflammation of the Oral Cavity

The oral cavity is a unique environment that consists of teeth surrounded by periodontal tissues, oral mucosae with minor salivary glands, and terminal parts of major salivary glands that open into the oral cavity. The cavity is constantly exposed to viral and microbial pathogens. Recent studies indicate that components of the plasminogen (Plg)/plasmin (Pm) system are expressed in tissues of the oral cavity, such as the salivary gland, and contribute to microbial infection and inflammation, such as periodontitis. The Plg/Pm system fulfills two major functions: (a) the destruction of fibrin deposits in the bloodstream or damaged tissues, a process called fibrinolysis, and (b) non-fibrinolytic actions that include the proteolytic modulation of proteins. One can observe both functions during inflammation. The virus that causes the coronavirus disease 2019 (COVID-19) exploits the fibrinolytic and non-fibrinolytic functions of the Plg/Pm system in the oral cavity. During COVID-19, well-established coagulopathy with the development of microthrombi requires constant activation of the fibrinolytic function. Furthermore, viral entry is modulated by receptors such as TMPRSS2, which is necessary in the oral cavity, leading to a derailed immune response that peaks in cytokine storm syndrome. This paper outlines the significance of the Plg/Pm system for infectious and inflammatory diseases that start in the oral cavity.

Association of COVID-19 Infection and Acute Mesenteric Ischemia

COVID-19 is an infectious disease that is considered to be a thromboinflammatory disorder. The study was aimed to determine the prevalence of COVID-19 in patients with acute mesenteric ischemia (AMI) and the outcomes of surgical treatment in relation to COVID-19. A total of 140 patients were included in this multicentric study divided into two groups: the test group (n=65) consisted of cases of AMI detected during the COVID-19 pandemic and the control group (n=65) consisted of cases of AMI detected before the pandemic. Test group patients were classified as COVID-positive (COVID+), or COVID-negative (COVID-) if they tested positive, respectively negative test for COVID-19 on admission. Primary outcomes were: prevalence of COVID-19 infection among test group patients, association between COVID-19 infection and inoperability, and between COVID-19 and treatment outcome. Secondary outcomes were association between each blood parameter and inoperability and treatment outcome. There were no statistically significant differences between inoperability and COVID-19 positivity on admission, overall mortality between the control group and the test group and overall mortality between COVID+ and COVID- patients, as well as among those patients that have been surgically treated (p>0.05). There were statistically significant differences between serum amylase levels (p=0.034), and serum LDH levels (p=0.0382) and inoperability, between serum LDH levels and postoperative mortality (p=0.0151), and overall mortality (p=0.00163). High level of LDH and serum pancreatic amylase are associated with a higher rate of inoperability and a higher postoperative and overall mortality rate. COVID-19 does not seem to independently influence the treatment outcome of AMI.

Thrombosis and lymphocyte subsets of COVID-19 omicron BA.2 variant patients with cancer

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused an ongoing global pandemic of COVID-19. It has been found that COVID-19 has an influence on the changes of blood coagulation parameters and the high incidence of thrombosis. Changchun experienced the epidemic of the Omicron BA.2 variant SARS-CoV-2 in March 2022 in China. Once infected, BA.2 spreads rapidly and most of them are asymptomatic. The purpose of this study is to research venous thrombosis and laboratory changes (including PLT, PT, APTT, DD, FDP, CRP, WBC, IL-6 and lymphocyte subsets) among 92 cancer patients with COVID-19 and 73 COVID-19 patients with non-cancer by Mann-Whitney U and Chi-square test. It was found that the levels of D-dimer, FDP, CRP and IL-6 in cancer patients were significantly higher than those in the COVID-19 cohort. There were 9 (9.8%) cancer patients and 2 (2.7%) non-cancer patients found VTE, with no significant difference. The results showed that WBC, lymphocytes and B cells in cancer patients were significantly lower than those in the other group. Prophylactic anticoagulation was recommended for cancer patients with high risk factors, while paying attention to the occurrence of bleeding events. The detection of leukocyte classification, D-dimer, prothrombin time and fibrinogen at different time points are helpful for the diagnosis and anticoagulation of COVID-19 patients with cancer.

Activated Platelets and Platelet-Derived Extracellular Vesicles Mediate COVID-19-Associated Immunothrombosis

Activated platelets and platelet-derived extracellular vesicles (EVs) have emerged as central players in thromboembolic complications associated with severe coronavirus disease 2019 (COVID-19). Platelets bridge hemostatic, inflammatory, and immune responses by their ability to sense pathogens via various pattern recognition receptors, and they respond to infection through a diverse repertoire of mechanisms. Dysregulated platelet activation, however, can lead to immunothrombosis, a simultaneous overactivation of blood coagulation and the innate immune response. Mediators released by activated platelets in response to infection, such as antimicrobial peptides, high mobility group box 1 protein, platelet factor 4 (PF4), and PF4⁺ extracellular vesicles promote neutrophil activation, resulting in the release of neutrophil extracellular traps and histones. Many of the factors released during platelet and neutrophil activation are positively charged and interact with endogenous heparan sulfate or exogenously administered heparin via electrostatic interactions or via specific binding sites. Here, we review the current state of knowledge regarding the involvement of platelets and platelet-derived EVs in the pathogenesis of immunothrombosis, and we discuss the potential of extracorporeal therapies using adsorbents functionalized with heparin to deplete platelet-derived and neutrophil-derived mediators of immunothrombosis.

Screening the Potential Biomarkers of COVID-19-Related Thrombosis Through Bioinformatics Analysis

A high proportion of critically ill patients with coronavirus disease 2019 (COVID-19) experience thrombosis, and there is a strong correlation between anticoagulant therapy and the COVID-19 survival rate, indicating that common COVID-19 and thrombosis targets have potential therapeutic value for severe COVID-19.Gene expression profiling data were downloaded from Gene Expression Omnibus (GEO), and common differentially expressed genes (co-DEGs) were identified. The potential biological functions of these co-DEGs were explored by functional enrichment analysis, and protein–protein interaction (PPI) networks were constructed to elucidate the molecular mechanisms of the co-DEGs. Finally, hub genes in the co-DEG network were identified, and correlation analysis was performed.We identified 8320 upregulated genes and 7651 downregulated genes from blood samples of COVID-19 patients and 368 upregulated genes and 240 downregulated genes from blood samples of thrombosis patients. The enriched cellular component terms were mainly related to cytosolic ribosomes and ribosomal subunits. The enriched molecular function terms were mainly related to structural constituents of ribosomes and electron transfer activity. Construction of the PPI network and identification of hub genes ultimately confirmed that RPS7, IGF1R, DICER1, ERH, MCTS1, and TNPO1 were jointly upregulated hub genes, and FLNA and PXN were jointly downregulated hub genes.The identification of novel potential biomarkers provides new options for treating COVID-19-related thrombosis and reducing the rate of severe COVID-19.