Imaging of Oxford/AstraZeneca® COVID-19 vaccine-induced immune thrombotic thrombocytopenia

Portal-splenic-mesenteric venous thrombosis in COVID-19 patients: a systematic review

The COVID-19 pandemic affected millions of people worldwide. In addition to respiratory impairment, this viral infection can also provoke gastrointestinal symptoms caused by vascular disorders, such as portal-splenic-mesenteric venous thrombosis (PSMVT). This systematic review aimed to investigate the profile of patients who developed PSMVT concomitant with or after viral infection and its predominant outcomes. The database searches returned 214 articles. Of these, 40 case reports were included in the review, presenting a total of 41 cases of PSMVT addressed. Males were more prevalent (n=27; 65.85%), mean age was 51.54 years, and 19.57% had a previous history of endocrine diseases. Statistically significant relationships (p<0.05) were found between patient death and tachypnea at hospital admission (p=0.043) and between patient death and age (p=0.019). It was therefore possible to identify the main profiles and risk factors for PSMVT development and mortality of COVID-19 infected patients.

ChAdOx1 nCoV-19 Vaccine and Thrombosis with Thrombocytopenia Syndrome among Adults: A Systematic Review

Several vaccine-induced thrombotic thrombocytopenia syndrome (VITTS) cases have been reported after the ChAdOx1 nCov-19 vaccination. The current study systematically reviewed the reported post-ChAdOx1 nCoV-19 vaccination thrombotic thrombocytopenia cases. Their laboratory and clinical features, as well as the diagnostic and therapeutic measures, were investigated. Online databases were searched until 25 August 2021. Studies reporting post-ChAdOx1 nCov-19 vaccination thrombotic thrombocytopenia syndrome (TTS) were included. Overall, 167 cases (21-77 years old) from 53 publications were included showing a female dominance of 1.75 times. About 85% of the cases exhibited the primary symptoms within the first two weeks post-vaccination. Headache was the most common initial symptom (>44.2%), and hemorrhage/thrombotic problems (22.46%), as well as discoordination/weakness/numbness/ hemiparesis/cyanotic toes (19.6%), were the most prevalent uncommon initial symptoms. Prothrombin time (PT), D-dimers, and C-reactive protein were the most remarkable increased laboratory parameters in 50.6%, 99.1%, and 55.6% of cases, respectively. In comparison, platelet and fibrinogen were the most remarkable decreased laboratory parameters in 92.7% and 50.5% of cases, respectively. Most VITT cases presented with cerebral venous thrombosis/cerebral venous sinus thrombosis, supraventricular tachycardia, transverse sinus/cerebral thrombosis, pulmonary embolism, and cerebral hemorrhage. Anti-PF4 antibody measurement through immunoassays and functional assays were positive in 86.2% and 73% of cases, respectively. About 31% of the cases died. Early diagnosis and proper therapeutic measures are important in ChAdOx1 nCov-19 vaccine-induced VITTS patients. Therefore, experts are recommended to know the corresponding clinical and laboratory features, as well as diagnostic methods. Elucidation of the pathophysiologic mechanism of ChAdOx1 nCov-19 vaccine-induced TTS deserves further investigation.

Blood Coagulation and Thrombotic Disorders following SARS-CoV-2 Infection and COVID-19 Vaccination

Although abundant data confirm the efficacy and safety profile of the developed vaccines against COVID-19, there are still some concerns regarding vaccination in high-risk populations. This is especially valid for patients susceptible to thrombotic or bleeding events and hesitant people due to the fear of thrombotic incidents following vaccination. This narrative review focuses on various inherited and acquired thrombotic and coagulation disorders and the possible pathophysiologic mechanisms interacting with the coagulation system during immunization in view of the currently available safety data regarding COVID-19 vaccines. Inherited blood coagulation disorders and inherited thrombotic disorders in the light of COVID-19, as well as blood coagulation and thrombotic disorders and bleeding complications following COVID-19 vaccines, along with the possible pathogenesis hypotheses, therapeutic interventions, and imaging for diagnosing are discussed in detail. Lastly, the lack of causality between the bleeding and thrombotic events and COVID-19 vaccines is debated, but still emphasizes the importance of vaccination against COVID-19, outweighing the minimal risk of potential rare adverse events associated with coagulation.

Acute ischemic stroke and vaccine-induced immune thrombotic thrombocytopenia post COVID-19 vaccination; a systematic review

INTRODUCTION

One of the rare but potentially serious side effects of COVID-19 vaccination is arterial and venous thrombosis. Acute ischemic stroke (AIS) cases have been reported post COVID-19 vaccination. Herein, we systematically reviewed the reported cases of AIS after COVID-19 vaccination.

METHOD

This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. We searched PubMed and Scopus until April 14, 2022 to find studies that reported AIS post COVID-19 vaccination.

RESULTS

We found 447 articles. From those, 140 duplicates were removed. After screening and excluding irrelevant articles, 29 studies (43 patients) were identified to be included. From all cases, 22 patients (51.1%) were diagnosed with AIS associated with Vaccine-induced immune thrombotic thrombocytopenia (VITT). Among AIS associated with VITT group, all received viral vector vaccines except one. The majority of cases with AIS and VITT were female (17 cases, 77.2%) and aged below 60 years (15 cases, 68%). Fourteen patients (32.5%) had additional thrombosis in other sites. Four of them (0.09%) showed concurrent CVST and ischemic stroke. Hemorrhagic transformation following AIS occurred in 7 patients (16.27%). Among 43 patients with AIS, at least 6 patients (14%) died during hospital admission.

CONCLUSION

AIS has been reported as a rare complication within 4 weeks post COVID-19 vaccination, particularly with viral vector vaccines. Health care providers should be familiar with this rare consequence of COVID-19 vaccination in particular in the context of VITT to make a timely diagnosis and appropriate treatment plan.

Thrombus Distribution in Vaccine-induced Immune Thrombotic Thrombocytopenia after ChAdOx1 nCoV-19 Vaccination

This case series reports 40 patients (median age, 41 years [interquartile range (IQR) 32- 52, 22 men) with confirmed vaccine-induced immune thrombotic thrombocytopaenia after administration of their first ChAdOx1 nCov-19 (AstraZeneca) vaccine: 80% (n=32) developed symptoms within the first 14 days and 20% (n=8) within 14-28 days. The location and extent of thrombi were evaluated using CT, MRI and ultrasound. Of the 40, 73% (n=29) presented with neurological symptoms and had confirmed cerebral venous sinus thrombosis, 30% (n=12) had extension of their primary thrombus, and 20% (n=8) died. 83% of those who underwent additional imaging (25 of 30) had occult thrombosis.

Stroke Associated with COVID-19 Vaccines

Objectives

Development of safe and effective vaccines against coronavirus disease 2019 (COVID-19) remains the cornerstone of controlling this pandemic. However, there are increasing reports of various types of stroke including ischemic stroke, and hemorrhagic stroke, as well as cerebral venous sinus thrombosis (CVST) after COVID-19 vaccination. This paper aims to review reports of stroke associated with COVID-19 vaccines and provide a coherent clinical picture of this condition.

Materials and methods

A literature review was performed with a focus on data from recent studies.

Results

Most of such patients are women under 60 years of age and who had received ChAdOx1 nCoV-19 vaccine. Most studies reported CVST with or without secondary ischemic or hemorrhagic stroke, and some with Vaccine-induced Thrombotic Thrombocytopenia (VITT). The most common clinical symptom of CVST seen after COVID-19 vaccination was headache. The clinical course of CVST after COVID-19 vaccination may be more severe than CVST not associated with COVID vaccination. Management of CVST following COVID-19 vaccination is challenging and may differ from the standard treatment of CVST. Low molecular weight heparin is commonly used in the treatment of CVST; however, it may worsen outcomes in CVST associated with VITT. Furthermore, administration of intravenous immunoglobulin and high-dose glucocorticoids have been recommended with various success rates.

Conclusion

These contradictory observations are a source of confusion in clinical decision-making and warrant further study and development of clinical guidelines. Clinicians should be aware of clinical presentation, diagnosis, and management of stroke associated with COVID-19 vaccination.

COVID-19, Vaccines, and Thrombotic Events: A Narrative Review

The coronavirus disease 2019 (COVID-19), a deadly pandemic that has affected millions of people worldwide, is associated with cardiovascular complications, including venous and arterial thromboembolic events. Viral spike proteins, in fact, may promote the release of prothrombotic and inflammatory mediators. Vaccines, coding for the spike protein, are the primary means for preventing COVID-19. However, some unexpected thrombotic events at unusual sites, most frequently located in the cerebral venous sinus but also splanchnic, with associated thrombocytopenia, have emerged in subjects who received adenovirus-based vaccines, especially in fertile women. This clinical entity was soon recognized as a new syndrome, named vaccine-induced immune thrombotic thrombocytopenia, probably caused by cross-reacting anti-platelet factor-4 antibodies activating platelets. For this reason, the regulatory agencies of various countries restricted the use of adenovirus-based vaccines to some age groups. The prevailing opinion of most experts, however, is that the risk of developing COVID-19, including thrombotic complications, clearly outweighs this potential risk. This point-of-view aims at providing a narrative review of epidemiological issues, clinical data, and pathogenetic hypotheses of thrombosis linked to both COVID-19 and its vaccines, helping medical practitioners to offer up-to-date and evidence-based counseling to their often-alarmed patients with acute or chronic cardiovascular thrombotic events.

Cardiovascular and haematological events post COVID-19 vaccination: A systematic review

Since COVID-19 took a strong hold around the globe causing considerable morbidity and mortality, a lot of effort was dedicated to manufacturing effective vaccines against SARS-CoV-2. Many questions have since been raised surrounding the safety of the vaccines, and a lot of media attention to certain side effects. This caused a state of vaccine hesitancy that may prove problematic in the global effort to control the virus. This review was undertaken with the aim of putting together all the reported cardiovascular and haematological events post COVID-19 vaccination in published literature and to suggest possible mechanisms to explain these rare phenomena.

Vaccine-induced thrombotic thrombocytopenia following coronavirus vaccine: A narrative review

The novel coronavirus pandemic has taken a toll on the global healthcare systems and economy. Safety precautions, along with vaccination, are the most effective preventive measures. The global vaccination program against COVID-19 has dramatically reduced the number of deaths and cases. However, the incidence of thrombotic events and thrombocytopenia post-COVID-19 vaccination known as vaccine-induced thrombotic thrombocytopenia has raised safety concerns. This has led to an element of vaccine hesitancy. The exact mechanism for vaccine-induced thrombotic thrombocytopenia is unknown. Although the incidence of thrombosis associated with COVID-19 vaccination is low, it still requires attention, especially in older people, smokers, and people with preexisting comorbidities. This study aims to review the pathophysiology, diagnosis, and management of vaccine-induced thrombotic thrombocytopenia, to provide a concise and comprehensive update.

Counting on COVID-19 Vaccine: Insights into the Current Strategies, Progress and Future Challenges

The emergence of a novel coronavirus viz., severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in late 2019 and its subsequent substantial spread produced the coronavirus disease 2019 (COVID-19) pandemic worldwide. Given its unprecedented infectivity and pathogenicity, the COVID-19 pandemic had a devastating impact on human health, and its clinical management has been a great challenge, which has led to the development and speedy trials of several vaccine candidates against SARS-CoV-2 at an exceptional pace. As a result, several COVID-19 vaccines were made commercially available in the first half of 2021. Although several COVID-19 vaccines showed promising results, crucial insights into their epidemiology, protective mechanisms, and the propensities of reinfection are not largely reviewed. In the present report, we provided insights into the prospects of vaccination against COVID-19 and assessed diverse vaccination strategies including DNA, mRNA, protein subunits, vector-based, live attenuated, and inactivated whole/viral particle-based vaccines. Next, we reviewed major aspects of various available vaccines approved by the World Health Organization and by the local administrations to use against COVID-19. Moreover, we comprehensively assessed the success of these approved vaccines and also their untoward effects, including the possibility of reinfection. We also provided an update on the vaccines that are under development and could be promising candidates in the future. Conclusively, we provided insights into the COVID-19 vaccine epidemiology, their potency, and propensity for SARS-CoV-2 reinfection, while a careful review of their current status, strategies, success, and future challenges was also presented.

Untangling the Intricacies of Infection, Thrombosis, Vaccination, and Antiphospholipid Antibodies for COVID-19

Advanced SARS-CoV-2 infections not uncommonly associate with the occurrence of silent or manifest thrombotic events which may be found as focal or systemic disease. Given the potential complexity of COVID-19 illnesses, a multifactorial causation is likely, but several studies have focused on infection-induced coagulopathy. Procoagulant states are commonly found in association with the finding of antiphospholipid antibodies. The correlation of the latter with thrombosis and/or clinical severity remains controversial. Although measures of antiphospholipid antibodies most commonly include assessments for lupus anticoagulant, anticardiolipin, and anti-ß2-glycoprotein-I antibodies, lesser common antibodies have been detected, and there remains speculation that other yet undiscovered autoimmune thrombotic events may yet be found. The recent discovery of post-vaccination thromboses associated with platelet factor 4 antibody has created another level of concern. The pathogenesis of antiphospholipid antibodies and their role in COVID-19-related thrombosis deserves further attention. The multifactorial nature of thrombosis associated with both infection and vaccination should continue to be studied as new events unfold. Even if a cause-and-effect relationship is variable at best, such dedicated research is likely to generate other valuable insights that are applicable to medicine generally.

Thrombosis with Thrombocytopenia Syndrome After Administration of AZD1222 or Ad26.COV2.S Vaccine for COVID-19: A Systematic Review

BACKGROUND

Cases of thrombosis with thrombocytopenia syndrome (TTS) have been reported following vaccination with AZD1222 or Ad26.COV2.S. This review aimed to explore the pathophysiology, epidemiology, diagnosis, management, and prognosis of TTS.

METHODS

A systematic review was conducted to identify evidence on TTS till 4th September 2021. Case reports and series reporting patient-level data were included. Descriptive statistics were reported and compared across patients with different sexes, age groups, vaccines, types of thrombosis, and outcomes.

FINDINGS

Sixty-two studies reporting 160 cases were included from 16 countries. Patients were predominantly females with a median age of 42.50 (22) years. AZD1222 was administered to 140 patients (87·5%). TTS onset occurred in a median of 9 (4) days after vaccination. Venous thrombosis was most common (61.0%). Most patients developed cerebral venous sinus thrombosis (CVST; 66.3%). CVST was significantly more common in female vs male patients (p = 0·001) and in patients aged <45 years vs ≥45 years (p = 0·004). The mortality rate was 36.2%, and patients with suspected TTS, venous thrombosis, CVST, pulmonary embolism, or intraneural complications, patients not managed with non-heparin anticoagulants or IVIG, patients receiving platelet transfusions, and patients requiring intensive care unit admission, mechanical ventilation, or inpatient neurosurgery were more likely to expire than recover.

INTERPRETATION

These findings help to understand the pathophysiology of TTS while also recommending diagnostic and management approaches to improve prognosis in patients.

FUNDING

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.