Venous or arterial thrombosis and deaths among COVID-19 cases: a European network cohort study.

BACKGROUND: There are few data on the incidence of thrombosis among COVID-19 cases, with most research concentrated on hospitalised patients. We aimed to estimate the incidence of venous thromboembolism, arterial thromboembolism, and death among COVID-19 cases and to assess the impact of these events on the risks of hospitalisation and death. METHODS: We conducted a distributed network cohort study using primary care records from the Netherlands, Italy, Spain, and the UK, and outpatient specialist records from Germany. The Spanish database was linked to hospital admissions. Participants were followed up from the date of a diagnosis of COVID-19 or positive RT-PCR test for SARS-CoV-2 (index date) for 90 days. The primary study outcomes were venous thromboembolic events, arterial thromboembolic events, and death, all over the 90 days from the index date. We estimated cumulative incidences for the study outcomes. Multistate models were used to calculate adjusted hazard ratios (HRs) for the association between venous thromboembolism or arterial thromboembolism occurrence and risks of hospitalisation or COVID-19 fatality. FINDINGS: Overall, 909 473 COVID-19 cases and 32 329 patients hospitalised with COVID-19 on or after Sept 1, 2020, were studied. The latest index dates across the databases ranged from Jan 30, 2021, to July 31, 2021. Cumulative 90-day incidence of venous thromboembolism ranged from 0·2% to 0·8% among COVID-19 cases, and up to 4·5% for those hospitalised. For arterial thromboembolism, estimates ranged from 0·1% to 0·8% among COVID-19 cases, increasing to 3·1% among those hospitalised. Case fatality ranged from 1·1% to 2·0% among patients with COVID-19, rising to 14·6% for hospitalised patients. The occurrence of venous thromboembolism in patients with COVID-19 was associated with an increased risk of death (adjusted HRs 4·42 [3·07-6·36] for those not hospitalised and 1·63 [1·39-1·90] for those hospitalised), as was the occurrence of arterial thromboembolism (3·16 [2·65-3·75] and 1·93 [1·57-2·37]). INTERPRETATION: Risks of venous thromboembolism and arterial thromboembolism were up to 1% among COVID-19 cases, and increased with age, among males, and in those who were hospitalised. Their occurrence was associated with excess mortality, underlying the importance of developing effective treatment strategies that reduce their frequency. FUNDING: European Medicines Agency.

Nitrous oxide misuse: a clue not to be missed in young patients with venous thromboembolism.

A 27-year-old man presented with altered mental status and unilateral right lower limb swelling. Brain imaging and cerebrospinal fluid analysis were unremarkable. He reported history of nitrous oxide misuse after he recovered from his delirium. The diagnosis of drug induced psychosis was made. The right lower limb swelling was found to be due to extensive deep vein thrombosis. In another case, a 21-year-old woman presented with headache, vomiting and dipoplia. Brain imaging showed extensive cerebral venous sinus thrombosis. She also misused nitrous oxide. Both cases had low-normal vitamin B12 and elevated methylmalonic acid, consistent with nitrous oxide misuse. The woman was found to have elevated homocysteine because of functional vitamin B12 deficiency. Homocysteine was not measured in the man. Raised homocysteine is associated with increased thrombosis risk. Fourteen cases of nitrous oxide misuse associated arterial and venous thrombosis have been reported. These two cases highlighted the importance of inquiring about recreational drug use in young patients who presented with apparently unprovoked venous thromboembolism.

Giant haematoma of the posterior compartment of thigh in a patient with coronavirus disease 19 pneumonia and pulmonary embolism - Case Report.

Introduction. During the Coronavirus-19 (Covid-19) pandemic, a significant increase in the frequency of complications in the form of venous thrombosis was observed. However, there is also the other side of the coin - an increase in the tendency to bleeding in the course of COVID19. Case Report. We present the case of a patient hospitalised in the COVID-19 Isolation Ward due to severe pneumonia in the course of SARS-CoV2 infection. She developed respiratory failure requiring a non-invasive mechanical ventilation. In addition, pulmonary embolism was diagnosed, the treatment with low molecule heparin was initiated. Soon, the patient developed a huge haematoma of the posterior compartment of the thigh causing deformation and dysfunction of the limb and resulting with acute haemorrhagic anaemia. Conclusion. Our article is a contribution to the discussion on the need to pay attention to the possibility of haemorrhagic complications in the course of anticoagulant treatment due to venous thrombosis in COVID-19 patients.

Shedding Light on the Pathogenesis of Splanchnic Vein Thrombosis.

Splanchnic vein thrombosis is a rare but potentially life-threatening manifestation of venous thromboembolism, with challenging implications both at the pathological and therapeutic level. It is frequently associated with liver cirrhosis, but it could also be provoked by myeloproliferative disorders, cancer of various gastroenterological origin, abdominal infections and thrombophilia. A portion of splanchnic vein thrombosis is still classified as idiopathic. Here, we review the mechanisms of splanchnic vein thrombosis, including new insights on the role of clonal hematopoiesis in idiopathic SVT pathogenesis, with important implications from the therapeutic standpoint.

Mortality and Deep Vein Thrombosis in the Gamma Variant of Covid 19 and Lung Injury.

Purpose: The SARS-CoV-2 disease predisposes infected individuals to thrombosis, the underlying mechanisms of which are not fully understood. The balance between pro-coagulant factors and natural coagulation inhibitors in critically ill patients with Covid-19 is fundamental to the prevention and treatment of complications. The aim of the present study was to investigate the pulmonary injury patterns in Covid-19 having higher mortality in the presence of deep vein thrombosis in comparison to patients without venous thrombosis and determine the Gamma variant. Methods: A retrospective study was conducted involving the evaluation of 200 medical records of patients with Covid-19 and a clinical suspicion of deep vein thrombosis (DVT) at the intensive care unit of a public hospital. The sample was divided into two groups of patients were formed - those positive and those negative for DVT. Statistical analysis involved the use of Fisher's exact test, the paired t-test and chi-square test. Results: Patients with DVT had more severe lung injuries (greater than 70%) compared to those without DVT (p = 0.003). Lesions affecting 50% to 70% of the lung area occurred in little more half of the group with DVT and just under half in the group without DVT (p = 0.5). Pulmonary lesions affecting less than 50% of the lung occurred more in patients without DVT (p = 0.0001). The Gamma variant increased prevalence of the both DVT and mortality (p=0.0001). Conclusion: Deep vein thrombosis is an aggravating factor of mortality in patients with SARS-CoV-2, and the Gamma variant is an aggravating factor of both thrombotic events and mortality.

New-onset and relapsed liver diseases following COVID-19 vaccination: a systematic review.

BACKGROUND: Liver diseases post-COVID-19 vaccination is extremely rare but can occur. A growing body of evidence has indicated that portal vein thrombosis, autoimmune hepatitis, raised liver enzymes and liver injuries, etc., may be potential consequence of COVID-19 vaccines. OBJECTIVES: To describe the results of a systematic review for new-onset and relapsed liver disease following COVID-19 vaccination. METHODS: For this systematic review, we searched Proquest, Medline, Embase, PubMed, CINAHL, Wiley online library, Scopus and Nature through the Preferred Reporting Items for Systematic Reviews and Meta Analyses PRISMA guideline for studies on the incidence of new onset or relapsed liver diseases post-COVID-19 vaccination, published from December 1, 2020 to July 31, 2022, with English language restriction. RESULTS: Two hundred seventy-five cases from one hundred and eighteen articles were included in the qualitative synthesis of this systematic review. Autoimmune hepatitis (138 cases) was the most frequent pathology observed post-COVID-19 vaccination, followed by portal vein thrombosis (52 cases), raised liver enzymes (26 cases) and liver injury (21 cases). Other cases include splanchnic vein thrombosis, acute cellular rejection of the liver, jaundice, hepatomegaly, acute hepatic failure and hepatic porphyria. Mortality was reported in any of the included cases for acute hepatic failure (n = 4, 50%), portal vein thrombosis (n = 25, 48.1%), splanchnic vein thrombosis (n = 6, 42.8%), jaundice (n = 1, 12.5%), raised liver enzymes (n = 2, 7.7%), and autoimmune hepatitis (n = 3, 2.2%). Most patients were easily treated without any serious complications, recovered and did not require long-term hepatic therapy. CONCLUSION: Reported evidence of liver diseases post-COIVD-19 vaccination should not discourage vaccination against this worldwide pandemic. The number of reported cases is relatively very small in relation to the hundreds of millions of vaccinations that have occurred and the protective benefits offered by COVID-19 vaccination far outweigh the risks.

Concomitant Guillain-Barré syndrome and cerebral venous thrombosis complicating a SARS-CoV-2 infection: a case report.

Cerebral venous thrombosis associated to acute inflammatory axonal polyneuropathy during infection with SARS-CoV-2 (coronavirus-2) is unusual. We describe the case of a 66-year-old patient with typical clinical and electrophysiological criteria of acute axonal motor neuropathy, who was positive for SARS-CoV-2. The symptoms started with fever associated with respiratory symptoms, and complicated one week later by headaches, and general weakness. The examination showed bilateral peripheral facial palsy, predominantly proximal tetraparesis, and areflexia with tingling of limbs were found. The whole was concomitant with the diagnosis of an acute polyradiculoneuropathy. Electrophysiologic evaluation confirmed the diagnosis. Cerebrospinal fluid examination showed albuminocytologic dissociation, and brain imaging revealed sigmoid sinus thrombophlebitis. Neurological manifestations improved during treatment with plasma exchange and anticoagulants. Our case draws attention to the occurrence of cerebral venous thrombosis and Guillain-Barré syndrome (GBS) in patients with COVID-19. The neuro-inflammation induced by the systemic immune response to infection, can lead to neurological manifestations. Further studies should be conducted on the full clinical spectrum of patients with COVID-19 with neurological symptoms.

Deep venous thrombosis and acute pericarditis associated with severe acute respiratory syndrome coronavirus 2 infection in a Congolese infant with sickle cell disease: a case report.

BACKGROUND: Since the beginning of the pandemic, no severe pediatric coronavirus disease 2019 cases have been described in Congo. CASE: We studied a 3-month-old male child of Congolese origin who was admitted to the pediatric department with 7-day history of fever, unilateral lower leg swelling, and dyspnea. There was no known history of contact with a coronavirus disease 2019 patient, and all the family members were asymptomatic. Nasopharyngeal swabs done at admission did not detect severe acute respiratory syndrome coronavirus 2. However, serology tests for severe acute respiratory syndrome coronavirus 2 antibodies were positive for immunoglobulin M and negative for immunoglobulin G. Hemoglobin electrophoresis showed hemoglobin A1, hemoglobin A2, hemoglobin F, and hemoglobin S of 46.2%, 2.5%, 19.9%, and 38.4%, respectively. Chest X-ray showed retrocardiac pneumonia in the left lung, and Doppler ultrasound of the left lower limb showed a recent total femoropopliteal venous thrombosis. At day 10 of hospitalization, our patient had classical signs of cardiac tamponade with a voluminous pericardial effusion seen on echocardiographic examination and elevated C-reactive protein, compatible with a diagnosis of constrictive pericarditis. To the best of the authors' knowledge, this is the first report of a case of plausible severe acute respiratory syndrome coronavirus 2 infection associated with venous thrombosis and acute pericarditis in Congo. CONCLUSION: We hypothesized that this case of venous thrombosis and acute pericarditis in a Congolese child with heterozygous sickle cell disease was related to severe acute respiratory syndrome coronavirus 2 infection.

Clinical Presentation and Short- and Long-term Outcomes in Patients With Isolated Distal Deep Vein Thrombosis vs Proximal Deep Vein Thrombosis in the RIETE Registry.

Importance: Insufficient data exist about the clinical presentation, short-term, and long-term outcomes of patients with isolated distal deep vein thrombosis (IDDVT), that is, thrombosis in infrapopliteal veins without proximal extension or pulmonary embolism (PE). Objective: To determine the clinical characteristics, short-term, and 1-year outcomes in patients with IDDVT and to compare the outcomes in unadjusted and multivariable adjusted analyses with patients who had proximal DVT. Design, Setting, and Participants: This was a multicenter, international cohort study in participating sites of the Registro Informatizado Enfermedad Tromboembólica (RIETE) registry conducted from March 1, 2001, through February 28, 2021. Patients included in this study had IDDVT. Patients with proximal DVT were identified for comparison. Patients were excluded if they had a history of asymptomatic DVT, upper-extremity DVT, coexisting PE, or COVID-19 infection. Main Outcomes and Measures: Primary outcomes were 90-day and 1-year mortality, 1-year major bleeding, and 1-year venous thromboembolism (VTE) deterioration, which was defined as subsequent development of proximal DVT or PE. Results: A total of 33 897 patients were identified with isolated DVT (without concomitant PE); 5938 (17.5%) had IDDVT (mean [SD] age, 61 [17] years; 2975 male patients [50.1%]), and 27 959 (82.5%) had proximal DVT (mean [SD] age, 65 [18] years; 14 315 male patients [51.2%]). Compared with individuals with proximal DVT, those with IDDVT had a lower comorbidity burden but were more likely to have had recent surgery or to have received hormonal therapy. Patients with IDDVT had lower risk of 90-day mortality compared with those with proximal DVT (odds ratio [OR], 0.47; 95% CI, 0.40-0.55). Findings were similar in 1-year unadjusted analyses (hazard ratio [HR], 0.52; 95% CI, 0.46-0.59) and adjusted analyses (HR, 0.72; 95% CI, 0.64-0.82). Patients with IDDVT had a lower 1-year hazard of VTE deterioration (HR, 0.83; 95% CI, 0.69-0.99). In 1-year adjusted analyses of patients without an adverse event within the first 3 months, IDDVT was associated with lower risk of VTE deterioration (adjusted HR, 0.48; 95% CI, 0.24-0.97). By 1-year follow-up, symptoms or signs of postthrombotic syndrome were less common in patients with IDDVT (47.6% vs 60.5%). Conclusions and Relevance: Results of this cohort study suggest that patients with IDDVT had a less ominous prognosis compared with patients with proximal DVT. Such differences were likely multifactorial, including the differences in demographics, risk factors, comorbidities, particularly for all-cause mortality, and a potential association of thrombus location with VTE deterioration and postthrombotic syndrome. Randomized clinical trials are needed to assess the optimal long-term management of IDDVT.

Management of Cerebral Venous Thrombosis Due to Adenoviral COVID-19 Vaccination.

OBJECTIVE: Cerebral venous thrombosis (CVT) caused by vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare adverse effect of adenovirus-based severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) vaccines. In March 2021, after autoimmune pathogenesis of VITT was discovered, treatment recommendations were developed. These comprised immunomodulation, non-heparin anticoagulants, and avoidance of platelet transfusion. The aim of this study was to evaluate adherence to these recommendations and its association with mortality. METHODS: We used data from an international prospective registry of patients with CVT after the adenovirus-based SARS-CoV-2 vaccination. We analyzed possible, probable, or definite VITT-CVT cases included until January 18, 2022. Immunomodulation entailed administration of intravenous immunoglobulins and/or plasmapheresis. RESULTS: Ninety-nine patients with VITT-CVT from 71 hospitals in 17 countries were analyzed. Five of 38 (13%), 11 of 24 (46%), and 28 of 37 (76%) of the patients diagnosed in March, April, and from May onward, respectively, were treated in-line with VITT recommendations (p < 0.001). Overall, treatment according to recommendations had no statistically significant influence on mortality (14/44 [32%] vs 29/55 [52%], adjusted odds ratio [OR] = 0.43, 95% confidence interval [CI] = 0.16-1.19). However, patients who received immunomodulation had lower mortality (19/65 [29%] vs 24/34 [70%], adjusted OR = 0.19, 95% CI = 0.06-0.58). Treatment with non-heparin anticoagulants instead of heparins was not associated with lower mortality (17/51 [33%] vs 13/35 [37%], adjusted OR = 0.70, 95% CI = 0.24-2.04). Mortality was also not significantly influenced by platelet transfusion (17/27 [63%] vs 26/72 [36%], adjusted OR = 2.19, 95% CI = 0.74-6.54). CONCLUSIONS: In patients with VITT-CVT, adherence to VITT treatment recommendations improved over time. Immunomodulation seems crucial for reducing mortality of VITT-CVT. ANN NEUROL 2022;92:562-573.

Clinical features of thrombosis and bleeding in COVID-19.

Infection with the SARS-CoV-2 virus, resulting in COVID-19 disease, has presented a unique scenario associated with high rates of thrombosis. The risk of venous thrombosis is some three- to sixfold higher than for patients admitted to a hospital for other indications, and for patients who have thrombosis, mortality appears to increase. Thrombosis may be a presenting feature of COVID-19. Pulmonary thrombi are the most frequent events, some related to deep vein thrombosis, but also to in situ microvascular and macrovascular thrombosis. Other venous thromboses include catheter- and circuit-associated in patients requiring hemofiltration and extracorporeal membrane oxygenation. Arterial thrombosis is less commonly documented, with 3% of patients in intensive care units having major arterial strokes and up to 9% having myocardial infarction, both of which are most likely multifactorial. Risk factors for thrombosis above those already documented in hospital settings include duration of COVID-19 symptoms before admission to the hospital. Laboratory parameters associated with higher risk of thrombosis include higher D-dimer, low fibrinogen, and low lymphocyte count, with higher factor VIII and von Willebrand factor levels indicative of more severe COVID-19 infection. All patients should receive thromboprophylaxis when admitted with COVID-19 infection, but the dose and length of treatment are still debated. Thrombosis continues to be treated according to standard VTE guidelines, but adjustments may be needed depending on other factors relevant to the patient's admission.

Portal Vein Thrombosis and Pyogenic Liver Abscess With Concomitant Bacteroides Bacteremia in a Patient With COVID-19 Infection: A Case Report and Brief Review.

The 2019 coronavirus disease (COVID-19) can present with a wide variety of clinical manifestations, including a hypercoagulable state leading to both arterial and venous thrombosis. Portal vein thrombosis (PVT) in the setting of COVID-19 has rarely been reported in the medical literature. Pylephlebitis with concomitant liver abscess is a rare complication of intra-abdominal infection. Here, we present the case of a 49-year-old man who initially presented with intermittent fevers and generalized weakness of 1-month duration and was subsequently found to have COVID-19 infection, PVT, and Bacteroides fragilis bacteremia with associated pyogenic liver abscess. The patient was treated with intravenous antibiotics and oral anticoagulation with plan to follow up outpatient with gastroenterology in 3 months to ensure resolution of PVT and liver abscess.

No increased incidence of venous thrombosis or pulmonary embolism after SARS-CoV-2 vaccination in Germany.

OBJECTIVES: Vaccination is one of the most effective measures to combat the COVID-19 pandemic. The main reason for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination hesitancy is the potential side-effects. This study aimed to investigate the incidence of venous thrombosis and pulmonary embolism in patients who received SARS-CoV-2 vaccination. STUDY DESIGN: This was a retrospective cohort study. METHODS: Individuals aged ≥18 years who received an initial vaccination for COVID-19 in one of 1134 general practices in Germany between April and June 2021 were included in the study. Vaccinated patients were matched to unvaccinated individuals by age, sex, index month (April to June 2020 [unvaccinated cohort] or April to June 2021 [vaccinated cohort]) and diagnoses that may be associated with an increased incidence of thrombosis documented within 12 months before the index date. The incidences of thrombosis and non-fatal pulmonary embolism as a function of COVID-19 vaccination were analysed. RESULTS: The present study included 326,833 individuals who were vaccinated against COVID-19 and 326,833 matched unvaccinated individuals. During the follow-up period, 406 vaccinated patients and 342 individuals in the control group received a diagnosis of thrombosis or non-fatal pulmonary embolism. This resulted in an incidence rate of 11.9 vs 11.3 cases per 1000 patient-years for vaccinated vs unvaccinated individuals, respectively, and a non-significant overall incidence rate ratio (IRR: 1.06; 95% confidence interval [CI]: 0.93-1.22). The highest IRR was observed in the 41-60 years age group (IRR: 1.30; 95% CI: 0.98-1.73), and the lowest IRR was seen in the 18-40 years age group (IRR: 0.6; 95% CI: 0.0-1.05); however, none of the individual age group incidence rates was significant. CONCLUSIONS: The results indicate that the occurrence of thrombosis or pulmonary embolism after COVID-19 vaccination is a coincidental finding rather than a consequence of vaccination.

Cerebral Venous Thrombosis in Patients With Heparin-Induced Thrombocytopenia a Systematic Review.

BACKGROUND: Cerebral venous thrombosis (CVT) has recently been reported as a common thrombotic manifestation in association with vaccine-induced thrombotic thrombocytopenia, a syndrome that mimics heparin-induced thrombocytopenia (HIT) and occurs after vaccination with adenovirus-based SARS-CoV-2 vaccines. We aimed to systematically review the incidence, clinical features, and prognosis of CVT occurring in patients with HIT. METHODS: The study protocol was registered with PROSPERO (CRD42021249652). MEDLINE, EMBASE and Cochrane CENTRAL were searched up to June 1, 2021 for HIT case series including >20 patients, or any report of HIT-related CVT. Demographic, neuroradiological, clinical, and mortality data were retrieved. Meta-analysis of proportions with random-effect modeling was used to derive rate of CVT in HIT and in-hospital mortality. Pooled estimates were compared with those for CVT without HIT and HIT without CVT, to determine differences in mortality. RESULTS: From 19073 results, we selected 23 case series of HIT (n=1220) and 27 cases of HIT-related CVT (n=27, 71% female). CVT developed in 1.6% of 1220 patients with HIT (95% CI,1.0%-2.5%, I2=0%). Hemorrhagic brain lesions occurred in 81.8% of cases of HIT-related CVT and other concomitant thrombosis affecting other vascular territory was reported in 47.8% of cases. In-hospital mortality was 33.3%. HIT-related CVT carried a 29% absolute increase in mortality rate compared with historical CVT controls (33.3% versus 4.3%, P<0.001) and a 17.4% excess mortality compared with HIT without CVT (33.3% versus 15.9%, P=0.046). CONCLUSIONS: CVT is a rare thrombotic manifestation in patients with HIT. HIT-related CVT has higher rates of intracerebral hemorrhage and a higher mortality risk, when compared with CVT in historical controls. The recently reported high frequency of CVT in patients with vaccine-induced thrombotic thrombocytopenia was not observed in HIT, suggesting that additional pathophysiological mechanisms besides anti-platelet factor-4 antibodies might be involved in vaccine-induced thrombotic thrombocytopenia-related CVT.

Neonatal Cerebral Venous Thrombosis following Maternal SARS-CoV-2 Infection in Pregnancy.

A possible consequence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is the development of an exacerbated thrombophilic status, and cerebral venous thrombosis (CVT) is a rare but possible complication of SARS-CoV-2 infection reported both in adults and in children. The present case report describes the clinical course of a term neonate showing extended CVT of unclear origin, whose mother had developed SARS-CoV-2 infection during the third trimester of pregnancy. We speculate that the prothrombotic status induced by maternal SARS-CoV-2 infection may have played a pathophysiological role in the development of such severe neonatal complication. Further investigations are required to confirm such hypothesis.

Cryptogenic, Embolic Stroke-Looking Backstage.

Stroke is a common and devastating event and the majority of cases are caused by thromboembolism from the left atrium, left ventricle or left sided valves. This case report describes a case of embolic stroke with the origin of the thrombus from the left inferior pulmonary vein. The importance of this case is twofold. Firstly, it is the fourth case report of pulmonary venous thrombosis, a very rare condition, due to COVID-19 infection and secondly, it focuses attention on the fact that the left atrium is not the most proximal address of arterial thromboembolism-the pulmonary veins are. Thus, it is proposed that a thorough assessment of the pulmonary veins should be done in all cases of arterial thromboembolism.

A Case of Intestinal Perforation Associated with Mesenteric Thrombosis Due to Post-COVID-19 Syndrome.

PURPOSE: We aimed to present a case who developed intestinal ischemia and associated perforation and abscess due to Superior Mesenteric Vein (SMV) thrombosis caused by post-COVID-19 syndrome and discuss the preoperative Computed Tomography (CT) imaging findings used in diagnosis. CASE PRESENTATION: A 58-year-old patient presented to our clinic with a complaint of acute abdominal pain. His CT examination revealed thrombosis in SMV, congestion in the mesenteric venous structures, contamination in the mesentery, and thickening and dilatation of the jejunal loops due to ischemia. The patient had a history of acute COVID-19 infection. He had typical COVID-19 pneumonia findings (peripheral ground-glass opacities in both lung parenchyma predominantly in the lower lobe) on the thorax CT at that time. He was followed up with anticoagulant therapy. During his follow-up, a thoracic and abdominal CT was performed due to recurrent acute abdominal findings. On thorax CT, there was a web-like filling defect consistent with pulmonary embolism, traction bronchiectasis consistent with late findings of COVID-19 pneumonia, and poorly circumscribed subpleural ground glass opacities. On abdominal CT, in addition to mesenteric ischemia findings, loss of wall integrity was observed in the jejunal loops due to perforation and collection areas containing air consistent with an abscess. He was treated with small bowel resection and abscess drainage. CONCLUSION: Patients with acute COVID-19 infection should be followed up for the early diagnosis of serious symptoms that may develop due to post-COVID-19 syndrome, and contrast-enhanced CT should be the imaging method of choice to detect possible mesenteric vascular thrombosis in patients with acute abdominal symptoms.

Characteristics of deep vein thrombosis in the critically ill COVID-19 patient - an observational cohort study with Doppler ultrasound measurements.

OBJECTIVE: COVID-19 is associated with an increased prevalence of deep venous thrombosis (DVT), mainly in the lower limbs. However, the characteristics and rheological conditions, which contribute to facilitating DVT occurrence have been poorly investigated. We aimed to report DVT characteristics, vein diameters and peak blood flow velocities (PBFV) in the common femoral veins (CFVs) of critically ill COVID-19 patients. PATIENTS AND METHODS: We conducted a prospective single-center cohort study in March-October 2020 including all consecutive mechanically ventilated COVID-19 adults. Doppler ultrasound of the lower limbs was performed systematically during the first week of hospitalization. In DVT-free patients, a second Doppler ultrasound was performed seven days later. Data are expressed as medians (interquartile ranges) or percentages. Comparisons were performed using Mann-Whiney and Wilcoxon signed-rank tests or Fischer's exact tests, as appropriate. RESULTS: Fifty-five patients [age, 63 years (56-74); female/male ratio, 0.62; body-mass index, 29 kg/m2 (26-33); hypertension, 47%; diabetes, 38%; ischemic heart disease, 11%] were included. DVT was diagnosed in 19 patients (35%) including in 5 femoral (9%), 2 popliteal (4%) and 12 below-the-knee sites (22%). CFV diameter was increased to 12.0 mm (11.0-15.0) (normal range, 9.1-12) and PBFV reduced to 11.9 cm/s (8.8-15.8) (normal range, 21.3-49.2) [right-side values]. In four patients who had ultrasound before intubation, CFV diameter increased from 12.5 mm (11.8-13.3) before to 14 mm (13.6-15.3) after intubation (p = 0.008). CONCLUSIONS: DVT in the CFV occurred in 9% of the critically ill COVID-19 patients with an overall 35%-DVT prevalence. Venous return difficulty evidenced by larger than normal CFV diameters and lower than normal PBFVs may have facilitated proximal DVT occurrence.

Association of AZD1222 and BNT162b2 COVID-19 Vaccination With Thromboembolic and Thrombocytopenic Events in Frontline Personnel : A Retrospective Cohort Study.

BACKGROUND: In March 2021, several European countries suspended the use of the AZD1222 (Oxford-AstraZeneca) COVID-19 vaccine because of thromboembolic safety concerns. Reports from Norway and Germany subsequently described patients with venous thrombosis and thrombocytopenia within 5 to 16 days of vaccination. OBJECTIVE: To evaluate the risk for outcomes related to thrombosis and thrombocytopenia after AZD1222 or BNT162b2 (Pfizer-BioNTech) COVID-19 vaccination. DESIGN: Nationwide exploratory retrospective cohort study. SETTING: Danish linkable registers on vaccinations, hospitalizations, occupation, and other covariates. PARTICIPANTS: 355 209 Danish frontline personnel designated for priority COVID-19 vaccination followed from 27 December 2020 (the day of the first COVID-19 vaccination in Denmark) to 13 April 2021. MEASUREMENTS: Study outcomes were cerebral venous sinus thrombosis, splanchnic vein thrombosis, pulmonary embolism, deep venous thrombosis, arterial thrombosis, thrombocytopenia, and death. Cumulative incidences of study outcomes within 28 days of vaccination and unvaccinated risk time were compared using adjusted survival curves resulting in risk differences (RDs) at day 28 after vaccination. Adjustment for birth cohort, sex, calendar period, occupation, comorbid conditions, and prescription drug use was included. RESULTS: Vaccination with AZD1222 versus no vaccination was associated with a significant RD at day 28 for deep venous thrombosis (RD, 8.35 [95% CI, 0.21 to 16.49] per 100 000 vaccinations). The RDs for cerebral venous sinus thrombosis (RD, 1.68 [CI, -0.64 to 4.00] per 100 000 vaccinations) and thrombocytopenia (RD, 2.39 [CI, -1.09 to 5.87] per 100 000 vaccinations) were not significant. No adverse associations were seen for BNT162b2 vaccination. LIMITATION: No medical record review; surveillance bias. CONCLUSION: In this exploratory retrospective cohort study among frontline personnel in Denmark, receipt of the AZD1222 vaccine was associated with a small excess risk for deep venous thrombosis. Although the corresponding risks for the more rare and severe thrombotic outcomes (such as cerebral venous sinus thrombosis) were not statistically significantly increased, statistical precision was low, and clinically relevant risks could not be excluded with certainty. There was no statistically significant association of BNT162b2 vaccination with thrombotic or thrombocytopenic events. PRIMARY FUNDING SOURCE: Lundbeck Foundation.