Successful treatment of vaccine-induced prothrombotic immune thrombocytopenia (VIPIT)

Extensive splanchnic vein thrombosis after SARS-CoV-2 vaccination: A Vascular Liver Disease Group (VALDIG) initiative

BACKGROUND AND AIMS

Since the introduction of SARS-CoV-2 vaccines, several cases of vaccine-induced immune thrombocytopenia and thrombosis (VITT) have been described, especially cerebral vein thrombosis. We aimed to retrospectively collect all new cases of acute onset first or recurrent splanchnic vein thrombosis (SVT) following a recent SARS-CoV-2 vaccination within the Vascular Liver Disease Group network.

APPROACH AND RESULTS

New cases of SVT were identified from April 2021 to April 2022; follow-up was completed on December 31, 2022. Criteria to define VITT were derived from previous studies. Data from a pre-COVID cohort of patients with SVT (N=436) were used for comparison of clinical presentation, etiology, and outcome. Twenty-nine patients were identified with SVT occurring with a median of 11 days (range 2-76) after the first (48%), second (41%), or third (10%) vaccination (ChAdOx1 nCov-19 (n=12) or BNT162b2 (n=14), other (n=3) Only 2 patients(7%) fulfilled criteria for definite VITT. Twenty (69%) had SVT at multiple sites, including 4 (14%) with concomitant extra-abdominal thrombosis. Only 28% had an underlying prothrombotic condition, compared to 52% in the pre-COVID SVT cohort ( p =0.01). Five patients (17%) underwent bowel resection for mesenteric ischemia, compared with 3% in pre-COVID SVT ( p <0.001). Two patients died shortly after diagnosis (7%).

CONCLUSIONS

Although definite VITT was rare, in 72% of cases, no other cause for SVT could be identified following SARS-CoV-2 vaccination. These cases were different from patients with nonvaccine-related SVT, with lower incidence of prothrombotic conditions, higher rates of bowel ischemia, and poorer outcome. Although SVT after SARS-CoV-2 vaccination is rare in absolute terms, these data remain relevant considering ongoing revaccination programs.

Management of coronavirus disease 2019 vaccine-induced cutaneous complications: A comprehensive literature review

Despite the numerous reports of cutaneous manifestations associated with vaccines for coronavirus disease 2019 (COVID-19), the relationship between COVID-19 vaccines and cutaneous side effects remains unevaluated. In this review, we examine these manifestations and their management. Reported dermatoses included injection-site reaction (early and delayed), type I allergic reaction, morbilliform eruption, pityriasis rosea, Sweet syndrome, lichen planus, psoriasis, herpes zoster reactivation, erythema multiforme, Stevens-Johnson syndrome, and toxic epidermal necrolysis (TEN). The most common COVID-19 vaccination-related cutaneous manifestations are delayed local reactions, approximately 66% of which are associated with the Moderna vaccine, and 33% with the Pfizer vaccine. Aside from mild injection-site reactions, severe reactions include anaphylaxis and TEN. Most reactions, except for Stevens-Johnson syndrome and anaphylaxis, though unpredictable and unpreventable are mild and can be treated symptomatically. Findings from this review should allow primary care physicians and dermatologists to reach faster diagnosis and initiate prompt intervention.

Diagnosis and Treatment of Cerebral Venous Thrombosis

OBJECTIVE

Cerebral venous thrombosis (CVT), thrombosis of the dural sinus, cerebral veins, or both, is a rare cerebrovascular disease. Although mortality rates after CVT have declined over time, this condition can result in devastating neurologic outcomes. This article reviews the latest literature regarding CVT epidemiology, details new factors associated with the development of CVT, and describes advances in CVT treatment. It also contains a discussion of future directions in the field, including novel diagnostic imaging modalities, and potential strategies to reduce the risks associated with CVT.

LATEST DEVELOPMENTS

The incidence of CVT may be as high as 2 per 100,000 adults per year. It remains a difficult condition to diagnose given its variable clinical manifestations and the necessity of neuroimaging for confirmation. The COVID-19 pandemic has revealed a novel CVT trigger, vaccine-induced immune thrombotic thrombocytopenia (VITT), as well as an association between COVID-19 infection and CVT. Although VITT is a very rare event, timely diagnosis and treatment of CVT due to VITT likely improves patient outcomes. Direct oral anticoagulants are currently being used to treat CVT and emerging data suggest that these agents are as safe and effective as vitamin K antagonists. The role of endovascular therapy to treat CVT, despite a recent clinical trial, remains unproven.

ESSENTIAL POINTS

The incidence of CVT has increased, outcomes have improved, and the use of direct oral anticoagulants to treat CVT represents an important advance in the clinical care of these patients. Rates of CVT as a complication of COVID-19 vaccines using adenoviral vectors are very low (<5 per million vaccine doses administered), with the benefits of COVID-19 vaccination far outweighing the risks.

Current evidence of COVID-19 vaccination-related cardiovascular events

Currently, the world is recovering from the shock of the coronavirus disease 2019 (COVID-19) pandemic; however, this situation is still fragile. Health authorities recommend administering COVID-19 vaccines as the safest and most reliable tool for eliminating COVID-19. Subsequent to the extensive administration of the COVID-19 vaccines, a series of cardiovascular adverse effects have been reported. This comprehensive review aimed to provide an update on the etiology, pathophysiology, clinical features, and management of the cardiovascular adverse events associated with COVID-19 vaccines, including myocarditis, pericarditis, thrombosis with thrombocytopenia syndrome, myocardial infarction, cardiac arrhythmias, hypertension, and stress-induced cardiomyopathy. The benefits of COVID-19 vaccination far outweigh the reported adverse events. It would be clinically important to provide diagnostic scoring systems to differentiate COVID-19-related cardiovascular adverse events from other causes and develop therapeutic approaches for their management. Further evaluation of cardiovascular adverse events of the COVID-19 vaccines is crucial for implementing vaccination programs and developing safer and more reliable vaccines.

An Unusual Case of Combined Thrombosis and Amegakaryocytopenia Resembling Thrombosis With Thrombocytopenia Syndrome Following COVID-19 Infection in an Unvaccinated Patient

As a global community, we have learned that the manifestations of severe acute respiratory syndrome coronavirus 2 (SAR-CoV-2), infection, or coronavirus disease 2019 (COVID-19), extends far beyond respiratory compromise. Thrombocytopenia is thought to occur secondary to increased platelet consumption. Platelet activation and platelet-mediated immune inflammation contribute towards the thromboembolic complications seen in COVID-19 patients. In this report, the authors present the unusual case of a 75-year-old female with a history of COVID-19 infection who presented with a transient ischemic attack, thrombocytopenia, and amegakaryocytopenia.

Platelet Activation and Cytokine Release of Interleukin-8 and Interferon-Gamma-Induced Protein 10 after ChAdOx1 nCoV-19 Coronavirus Vaccine Injection

Coronavirus disease 2019 (COVID-19) vaccines are associated with serious thromboembolic or thrombocytopenic events including vaccine-induced immune thrombocytopenia and thrombosis and immune thrombocytopenia, particularly AZD1222/ChAdOx1. According to the proposed mechanism, COVID-19 vaccines stimulate inflammation and platelet activation. In this study, we analyzed the role of AZD1222/ChAdOx1 vaccines in the activation of platelets and the release of anti-PF4 antibodies and inflammatory cytokines in a cohort of healthy donors without vaccine-induced immune thrombotic thrombocytopenia (VITT). Forty-eight healthy volunteers were enrolled in this study. Blood samples were collected from peripheral blood at three time points: before vaccination and 1 and 7 days after vaccination. Compared with the prevaccination data, a decrease in the leukocyte and platelet counts was observed 1 day after vaccination, which recovered 7 days after injection. The percentage of activated GPIIb/IIIa complex (PAC-1) under high ADP or thrombin receptor-activating peptide stimulation increased 1 day after vaccination. Furthermore, interluekin-8 (IL-8) and interferon-gamma-induced protein 10 (IP-10) increased significantly. Additionally, platelet activation and inflammation, with the release of cytokines, were observed; however, none of the individuals developed VITT. Mild thrombocytopenia with platelet activation and inflammation with an elevation of IL-8 and IP-10 were observed after AZ vaccination.

Immune Thrombocytopenia and Cerebral Venous Sinus Thrombosis Following COVID-19 Vaccination: A Case Report

Mass vaccination against coronavirus disease 2019 (COVID-19) has been safe and effective. The ongoing emergence of vaccine-induced complications has challenged the public trust in vaccination programs and, though uncommon, can lead to significant morbidity and mortality. Vaccine-induced immune thrombocytopenia and thrombosis (VITT) is a rare and fatal complication of the COVID-19 vaccine. We present a rare case of VITT in a young female who presented with worsening headache, body rash with deteriorating neurological deficit after 12 days of the second dose of the ChAdOx1 COVID-19 vaccine. Initial blood tests showed thrombocytopenia with deranged clotting time and D-dimer levels. Her computed tomography venogram showed thrombosis in the left transverse sinus, and she was diagnosed with a provisional diagnosis of VITT. She initially managed with dexamethasone, intravenous immunoglobulins, and apixaban to reverse the autoimmune process. Our case highlights the clinical course, diagnosis, and management of VITT, which will assist physicians in the timely recognition and adequate management of VITT.

Thrombocytopenia and pneumonitis associated with BNT16B2b2 mRNA COVID-19 vaccine: A case report

An 80-year-old Japanese male patient with Behçet's disease presented with a seven-day history of fever, cough, and progressive shortness of breath after receiving a second dose of the BNT16B2b2 mRNA COVID-19 vaccine (Pfizer-BioNTech). The initial diagnosis was community-acquired pneumonia, and antibiotic treatment was started but proved ineffective. Twenty days after onset, his platelet count was significantly decreased. We suspected vaccine-induced pneumonitis and thrombocytopenia. After administration of prednisolone and intravenous immunoglobulin, and platelet transfusions, his platelet count normalized. The pneumonia symptoms improved three weeks after onset. Herein, we also summarize previous reports of cases of pneumonitis and thrombocytopenia associated with SARS-CoV-2 vaccination.

Autoimmune and autoinflammatory conditions after COVID-19 vaccination. New case reports and updated literature review

Autoimmunity linked to COVID-19 immunization has been recorded throughout the pandemic. Herein we present six new patients who experienced relapses of previous autoimmune disease (AD) or developed a new autoimmune or autoinflammatory condition following vaccination. In addition, we documented additional cases through a systematic review of the literature up to August 1st, 2022, in which 464 studies (928 cases) were included. The majority of patients (53.6%) were women, with a median age of 48 years (IQR: 34 to 66). The median period between immunization and the start of symptoms was eight days (IQR: 3 to 14). New-onset conditions were observed in 81.5% (n: 756) of the cases. The most common diseases associated with new-onset events following vaccination were immune thrombocytopenia, myocarditis, and Guillain-Barré syndrome. In contrast, immune thrombocytopenia, psoriasis, IgA nephropathy, and systemic lupus erythematosus were the most common illnesses associated with relapsing episodes (18.5%, n: 172). The first dosage was linked with new-onset events (69.8% vs. 59.3%, P = 0.0100), whereas the second dose was related to relapsing disease (29.5% vs. 59.3%, P = 0.0159). New-onset conditions and relapsing diseases were more common in women (51.5% and 62.9%, respectively; P = 0.0081). The groups were evenly balanced in age. No deaths were recorded after the disease relapsed, while 4.7% of patients with new-onset conditions died (P = 0.0013). In conclusion, there may be an association between COVID-19 vaccination and autoimmune and inflammatory diseases. Some ADs seem to be more common than others. Vaccines and SARS-CoV-2 may induce autoimmunity through similar mechanisms. Large, well-controlled studies are warranted to validate this relationship and assess additional variables such as genetic and other environmental factors.

Possible COVID-19 MRNA Vaccine-Induced Case of Unilateral Central Retinal Vein Occlusion

PURPOSE

To report a case of a patient with central retinal vein occlusion (CRVO), 2 weeks after the first dose of a COVID-19 mRNA vaccine.

RESULTS

A 35-year-old man presented with decreased vision on his right eye, 2 weeks after receiving the first dose of COVID-19 mRNA vaccine. During examination, signs of right CRVO were found. We started general checkup of the patient, extended with laboratory tests specific for VIPIT. No exact cause of the thromboembolic episode could be documented. With the applied therapy, symptoms resolved completely.

CONCLUSION

CRVO after COVID-19 mRNA vaccination is reported only in one case in the literature. In our case, the young age of the patient, the close onset of the symptoms to the vaccination and the negative systemic, immunologic and hematologic tests are suggesting a vaccine-induced thrombotic mechanism. We propose further investigation of vaccine-induced thrombotic mechanisms and also close follow of the reported cases.

Effectiveness of SARS-CoV-2 Vaccines for Short- and Long-Term Immunity: A General Overview for the Pandemic Contrast

BACKGROUND

The recent COVID-19 pandemic produced a significant increase in cases and an emergency state was induced worldwide. The current knowledge about the COVID-19 disease concerning diagnoses, patient tracking, the treatment protocol, and vaccines provides a consistent contribution for the primary prevention of the viral infection and decreasing the severity of the SARS-CoV-2 disease. The aim of the present investigation was to produce a general overview about the current findings for the COVID-19 disease, SARS-CoV-2 interaction mechanisms with the host, therapies and vaccines' immunization findings.

METHODS

A literature overview was produced in order to evaluate the state-of-art in SARS-CoV-2 diagnoses, prognoses, therapies, and prevention.

RESULTS

Concerning to the interaction mechanisms with the host, the virus binds to target with its Spike proteins on its surface and uses it as an anchor. The Spike protein targets the ACE2 cell receptor and enters into the cells by using a special enzyme (TMPRSS2). Once the virion is quietly accommodated, it releases its RNA. Proteins and RNA are used in the Golgi apparatus to produce more viruses that are released. Concerning the therapies, different protocols have been developed in observance of the disease severity and comorbidity with a consistent reduction in the mortality rate. Currently, different vaccines are currently in phase IV but a remarkable difference in efficiency has been detected concerning the more recent SARS-CoV-2 variants.

CONCLUSIONS

Among the many questions in this pandemic state, the one that recurs most is knowing why some people become more seriously ill than others who instead contract the infection as if it was a trivial flu. More studies are necessary to investigate the efficiency of the treatment protocols and vaccines for the more recent detected SARS-CoV-2 variant.

Side Effects Related to BNT162b2 and CoronaVac Vaccine Requiring Emergency Department Visit

Background  Currently, the most effective method in the fight against coronavirus disease 2019 (COVID-19) is vaccination against the disease. However, there are hesitations among society concerning the safety and side effects of COVID-19 vaccines. We aimed to determine the observed side effects that require an emergency room visit after taking the BNT162b2 and CoronaVac vaccines.

Methods  This prospective observational study was conducted with patients who presented to the emergency department due to vaccine-related complications after COVID-19 vaccination. The patients' symptoms at the time of presentation, time from vaccination to the onset of symptoms, and dose of the vaccine administered were determined. In addition, the demographic characteristics of the patients, whether they had a history of COVID-19 infection, and their vital signs at the time of presentation were recorded. The variables were compared according to the type of vaccine administered.

Results  The study included 182 patients who presented to the emergency department over a 6-month period. It was determined that 166 of these patients (91.2%) had received the BNT162b2 vaccine and 16 (8.8%) had received the CoronaVac vaccine. The majority of the patients did not have a history of COVID-19 infection (70.3%), and most presented to the hospital with complications after the second dose (61%). The onset of vaccine-related symptoms was mostly within 1 to 12 hours (39%). The majority of patients (97.8%) were discharged from the emergency department. The most common symptoms after vaccination were fatigue ( n  = 70), followed by muscle/joint pain ( n  = 52), headache ( n  = 33), and fever ( n  = 32). The rate of dizziness was found to be statistically significantly higher in the CoronaVac vaccine group than in the BNT162b2 vaccine group ( p  = 0.008). There was no statistically significant difference between the two vaccine groups in relation to the remaining symptoms ( p  > 0.005).

Conclusion  There were no serious complications related to the BNT162b2 or CoronaVac vaccine. The most common symptom after both vaccines was fatigue; therefore, the BNT162b2 and CoronaVac vaccines can be safely administered.

Prescribing Practices of Intravenous Immunoglobulin in Tertiary Care Hospitals in Malaysia: A Need for a National Guideline for Immunoglobulin Use

Rational use of drug involves the use of medicine as per clinical guidelines. Given the steady increase in the clinical utility of intravenous immunoglobulin (IVIG) either as licensed or off-label use, concerns are being raised about the possibility of supply shortages that could significantly impact patient care. Therefore, there is a need to regulate and to promote the rational use of this valuable medication. This cross-sectional chart review study attempts to evaluate the prescribing patterns of IVIG at two tertiary hospitals in Malaysia. Patients’ medical files and dispensing records were examined and compared with current guidelines. A total of 348 prescriptions for IVIG were written during the 1-year study period. The highest usage of IVIG was for neurological (47.9%), immunological (27.5%), and hematological conditions (20%). The number of prescriptions with the US Food and Drug Administration (FDA) licensed indications and off-label indications was 148 (42.5%) and 200 (57.5%), respectively. Age (OR: 1.02, 95% CI: 1.01–1.03, p = 0.003) and those admitted to the critical care units (OR: 11.11, 95% CI: 5.60–22.05, p < 0.001) were significant factors for receiving IVIG for an off-label indication. Most prescriptions (79%) had appropriate dosing. Significant factors associated with receiving inappropriate dose of IVIG include age (OR: 0.93, 95% CI: 0.89–0.97, p = 0.001) and those admitted to the critical care units (OR: 10.15, 95% CI: 3.81–27.06, p < 0.001). This study advocates the development and implementation of evidence-based clinical guidelines with prioritization protocol to ensure rational use of IVIG.

Vaccine-induced immune thrombotic thrombocytopenia after ChAdOx1 nCoV-19 vaccine in an older patient: Minireview and a case report

Rare cases of unusual thrombosis and thrombocytopenia after administration of the ChAdOx1 nCoV-19 vaccine (AstraZeneca) have been reported. The unusual symptoms are called vaccine-induced immune thrombotic thrombocytopenia (VITT). In the present study, a brief background about cases of unusual thrombosis and thrombocytopenia after administration of the ChAdOx1 nCoV-19 was provided. In addition, a description of a case of a 66-year-old woman who had received this vaccine and developed VITT was done. She presented to the hospital complaining of hematomas in the right upper limb 14 days after the ChAdOx1 nCoV-19 vaccine, without a history of trauma (Glasgow coma scale of 14) and thrombocytopenia even though signs of thrombosis were absent. Cranium computed tomography scan indicated intraparenchymal hematoma and cerebral thrombosis, besides anastomotic Labbé vein thrombosis. The woman received platelets transfusion, dexamethasone, and neuroprotection measures, but even so, on the twelfth postoperative day, she died of cerebral rebleeding. In conclusion, it is crucial to point out the immuno-hypersensitivity mechanisms associated with ChAdOx1 nCoV-19 vaccine reactions, helping to reduce their occurrences and reinforcing confidence in vaccine administration.

Vaccine‐induced prothrombotic immune thrombocytopenia without thrombosis may not require immune modulatory therapy: A case report

Background

Vaccine‐induced immune thrombotic thrombocytopenia (VITT) is a rare complication of the ChAdOx1 nCoV‐19 and Ad26.COV2.S COVID‐19 vaccines. It presents most commonly with severe thrombocytopenia and thrombotic complications with extremely high D‐dimer levels 5–30 days after vaccination. We report a patient who presented with mild thrombocytopenia and minimally elevated D‐dimer levels without thrombosis, but who tested positive for antiplatelet factor 4 (PF4) platelet‐activating antibodies on a PF4‐enhanced serotonin‐release assay.

Key Clinical Question

Is immunomodulation necessary in patients who present without thrombosis?

Clinical Approach and Conclusions

Treatment with rivaroxaban alone was followed by platelet normalization despite persistence of anti‐PF4 antibodies. This case provides support that vaccination for COVID‐19 can induce a broad, heterogeneous prothrombotic disorder characterized by anti‐PF4 platelet‐activating antibodies that shares features with classical heparin‐induced thrombocytopenia (HIT) and autoimmune HIT syndromes and that immunomodulation may not be required in those without thrombosis.

Early recognition and treatment of pre-VITT syndrome after adenoviral vector-based SARS-CoV-2 vaccination may prevent from thrombotic complications: review of published cases and clinical pathway

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare but highly morbid complication after adenoviral vector-based SARS-CoV-2 vaccination. The pre-VITT syndrome is defined as vaccine-induced immune thrombocytopenia without thrombosis typically presenting with new-onset headache. This review aims to identify at-risk patients before complications such as cerebral venous sinus thrombosis occur. We review previously published reports of 19 patients (median age 35 years, range 23-74; 16 females) who met the diagnostic criteria for a pre-VITT syndrome. Seven patients progressed to VITT, 12 patients did not. Patients who experienced VITT received delayed treatment. The median interval between the onset of headache and VITT-treatment (i.e. anticoagulation, immune globulins, or corticosteroids) was 5 days (range 1-8 days) compared with 2 days (0-5 days) in those without subsequent VITT (P = 0.033). The interval from onset of headache to anticoagulation was longer in patients with VITT (median 7 vs. 2 days; range 3-9 vs. 0-7 days; P = 0.01). Anticoagulation was safe in all patients with a pre-VITT syndrome as no haemorrhagic complications occurred after anticoagulation was started despite low platelets. The transient decline of platelet count after admission was significantly more pronounced in patients who progressed to VITT (median 67 vs. 0 × 10³/µL; range 0-77 × 10³/µL vs. 0-10 × 10³/µL; P = 0.005). d-dimers did not differ between groups. Pre-VITT syndrome is a 'red flag' and allows to identify and preemptively treat patients at-risk of further progression to VITT. However, it must be distinguished from post-vaccination immune thrombocytopenia.

Superficial venous thrombosisas a possible consequence of ChAdOx1 nCoV-19 vaccine: two case reports

Background

Many scientists across the world got involved in the race to develop successful anti-SARS-CoV-2 vaccines to overcome COVID-19 pandemic. Among the different vaccines developed against SARS-CoV-2, Covishield was the first vaccine approved for emergency use in Nepal. We report two cases of Superficial Vein Thrombosis (SVT) for the first time in the literature after vaccination with the Chimpanzee Adenovirus-vectored Vaccine (ChAdOx1 nCoV-19 vaccine).

Cases presentation

Two cases, a 24-year-old young Chhetri male and a 62-year-old Chhetri female who have received Covishield (ChAdOx1 nCoV-19) vaccine, developed pain in left calf after 2 weeks and 10 weeks of vaccination, respectively. Both the case belongs to the Chhetri ethnic group of Nepal. The pain became severe on the fourth week of immunization in the first case while the pain was acute and severe on the 10^th week of vaccination in the second case. The first presented to emergency room and second case was referred to the emergency room from Orthopedic Clinic. On evaluation the first patient had normal vitals with no history of fever and swelling yet displayed non-radiating mild to moderate intensity pain localized to left leg below the knee which became aggravated by movements. In the second case however pain was more intense with other characteristics as first case. Both cases had low wells score (< 4). On local examination tenderness was noted on squeezing but other systemic examination findings of the patient were within normal limits in both cases. Among the numerous vaccines used to fight the battle against COVID-19 disease, the ChAdOx1 nCoV-19 vaccine, Covishield, has been widely used in Nepal and India. Apart from other minor side effects, in few cases thromboses have been reported after vaccination of ChAdOx1 nCoV-19, Covishield, vaccine.

Conclusion

These cases reporting Superficial Vein Thrombosis may be an additional adverse effect to the list of adverse events associated with ChAdOx1 nCoV-19, Covishield, vaccine. However, the benefits of the vaccine in breaking the chain of COVID 19 spread are certainly greater than the risk of thromboses.

The Chimpanzee Adenovirus-vectored Vaccine (ChAdOx1 nCoV-19 vaccine) has been widely used in Himalayan Country, Nepal and India.

Apart from other minor side effects, delayed thromboses in superficial vein have been reported after vaccination of ChAdOx1 nCoV-19 vaccine and they may be the consequences of vaccination though larger study is needed to verify them.

Superficial vein thrombosis (SVT) should be an additional adverse effect to be mentioned in the list of adverse events associated with ChAdOx1 nCoV-19, Covishield, vaccine.

The benefits of the vaccine in breaking the chain of COVID 19 spread are certainly greater than the risk of thromboses.

A systematic review of vaccine-induced thrombotic thrombocytopenia in individuals who received COVID-19 adenoviral-vector-based vaccines

Reports of thrombotic response after receiving COVID-19 Adenoviral-Vector Based Vaccines raise concerns about vaccine-induced thrombotic thrombocytopenia (VITT); therefore, we conduct this systematic review to report susceptible demographics outcomes, commonalities, and prognosis of reporting cases. We identified published articles by searching PubMed, SCOPUS, and Web of Science from December 2020 till May 2021, with an updated search in September 2021. All case reports and case series reporting thrombotic response after receiving COVID-19 Adenoviral-Vector Based Vaccines were eligible for including. In addition, two authors independently extracted data and assessed the quality of the included studies. A total of 157 patients with thrombotic events after the ChAdOx1 nCoV-19 vaccine and 16 patients with thrombotic events after Ad26.COV2. S vaccine was included in our study. 72% of the ChAdOx1 nCoV-19 cases were females, while in Ad26.COV2.S subgroup, all reported patients were females. The commonest presentations were deep vein thrombosis 20 (12.7%) and cerebral venous sinus thrombosis 18 (11.5%) in the ChAdOx1 nCoV-19 subgroup while cerebral venous sinus thrombosis 14 (87.5%) and pulmonary embolism 2 (12.5%) in the Ad26.COV2. S subgroup. In this study, we described the certain demographics associated with VITT and the clinical presentations of those cases in the ChAdOx1 nCoV-19 and Ad26.COV2. S vaccines. Young individuals, particularly females, may be more susceptible to VITT, and future studies should seek to confirm this association. In addition, the clinical presentation of VITT commonly includes cerebral thrombi, pulmonary embolism, and deep venous thrombosis, but other presentations are also possible, highlighting the importance of clinical vigilance in recent vaccine recipients.

Vaccine-induced immune thrombotic thrombocytopenia and patients with cancer

Vaccines to combat SARS-CoV-2 infection and the COVID-19 pandemic were quickly developed due to significant and combined efforts by the scientific community, government agencies, and private sector pharmaceutical and biotechnology companies. Following vaccine development, which took less than a year to accomplish, randomized placebo controlled clinical trials enrolled almost 100,000 people, demonstrating efficacy and no major safety signals. Vaccination programs were started, but shortly thereafter a small number of patients with a constellation of findings including thrombosis in unusual locations, thrombocytopenia, elevated D-dimer and often low fibrinogen led another intense and concentrated scientific effort to understand this syndrome. It was recognized that this occurred within a short time following administration of adenoviral vector SARS-CoV-2 vaccines. Critical to the rapid understanding of this syndrome was prompt communication among clinicians and scientists and exchange of knowledge. Now known as vaccine-induced immune thrombotic thrombocytopenia syndrome (VITT), progress has been made in understanding the pathophysiology of the syndrome, with the development of diagnostic criteria, and most importantly therapeutic strategies needed to effectively treat this rare complication of adenoviral vector vaccination. This review will focus on the current understanding of the pathophysiology of VITT, the findings that affected patients present with, and the rational for therapies, including for patients with cancer, as prompt recognition, diagnosis, and treatment of this syndrome has resulted in a dramatic decrease in associated mortality.

Thrombotic thrombocytopenia After Sinopharm BBIBP-CorV COVID-19 vaccination

Background

Severe side effects after vaccination with coronavirus disease 2019 (COVID-19) vaccines are rare but can be fatal. To date, vaccine-induced immune thrombotic thrombocytopenia (VITT) cases have been reported after injection of mRNA and adenoviral vectors COVID-19 vaccines. Here, we report the second suspected case of VITT after vaccination with the Sinopharm vaccine, an inactive vaccine.

Key Clinical Question

The Key Clinical Question was to determine whether inactivated COVID-19 vaccines could induce VITT and how to diagnose and treat such cases.

Clinical Approach and Conclusions

Our patient developed deteriorating symptoms the day after vaccination and was admitted to the emergency department on day 5 after vaccination. After performing laboratory analysis, thrombosis with thrombocytopenia was suggested, further confirmed by highly positive anti-heparin-platelet factor 4 antibodies assay and color Doppler ultrasonography. He was then treated with high-dose intravenous immunoglobulin, corticosteroid, and nonheparin anticoagulant.

Relationship between blood clots and COVID-19 vaccines: A literature review

SARS-CoV-2 pandemic is one of the most critical pandemics during human civilization. Several therapeutic strategies for COVID-19 management have been offered; nonetheless, none of them seems to be sufficiently beneficial. In effect, vaccines have been proffered as a viable option. The critical issue now is to concentrate on protecting individuals against illness through immunization. One of the causes for concern among the researchers, physicians, and generally the whole community from the onset of vaccination has been the adverse effects (specifically blood clots) that may be observed after the injection of the COVID-19 vaccine. In some countries, such concerns have even resulted in the temporary or permanent discontinuation or abandonment of the application of some vaccines (especially AstraZeneca and Janssen). By evaluating rigorous studies published on this subject, the present article is aimed at identifying the association between blood clot incidence and COVID-19 vaccination. Various methods for producing the COVID-19 vaccines are analyzed, along with their possible pros and cons as well as common and rare side effects, especially VITT and blood clots. Finally, the differences of various vaccines on thrombotic events, WHO recommendations for VITT treatment, and blood clots statics are discussed.

Vaccine-Inducted Thrombotic Thrombocytopenia and Covid-19 Vaccines: Case Series

Vaccine-induced thrombotic thrombocytopenia (VITT) is a condition similar to heparin-induced thrombocytopenia (HIT), but it is associated with prior administration of COVID-19 vaccines without prior exposure to heparin. The incidence of VITT is not certain, but it appears to be extremely rare. Reports of unusual and severe thrombotic events, including cerebral and splanchnic venous thrombosis and other autoimmune adverse reactions, such as immune thrombocytopenia or thrombotic microangiopathies in connection with some of the SARS-CoV-2 vaccines, have caused a great deal of concern within the population and the medical community. We would like to present 4 clinical cases of VITT, hospitalized and treated in intensive care unit (ICU) of University clinic of cardiology in Skopje.

Inflammatory Bowel Diseases in Renal Transplantat Recipients: A Case Series and Review of the Literature

Inflammatory bowel diseases are autoimmune disorders affecting the gastrointestinal tract and producing a wide variety of extraintestinal manifestations. Kidneys are a rare target organ of their extraintestinal activity, but if affected, renal function could deteriorate to end-stage kidney disease, which is curable only by organ transplantation. Renal calculi are the most common pathological kidney manifestation in IBD patients, followed by tubulointerstitial nephritis, glomerulonephritis, and other kidney pathologies. The liver is the most commonly transplanted organ in IBD patients (primary sclerosing cholangitis and autoimmune hepatitis), and a scarcity of literature on kidney recipients is present to date regarding the incidence of renal insufficiency, kidney transplantations, post-transplant IBD course and further complications such as graft rejection or infections in this specific group of patients. De novo IBD is a paradoxical entity in the setting of rigorous post-transplant immunosuppression. In this case series, we present three patients who underwent kidney transplantation with a history of an IBD and one patient who developed de novo Crohn's disease after the deceased donor organ transplant was performed.

SARS-CoV-2 Vaccine-Induced Immune Thrombotic Thrombocytopenia with Venous Thrombosis, Pulmonary Embolism, and Adrenal Haemorrhage: A Case Report with Literature Review

Vaccine-induced immune thrombotic thrombocytopenia (VITT) with venous thrombosis is a rare complication of SARS-CoV-2 vaccination with ChAdOx1 (AstraZeneca) and AD26.COV2.S (Johnson & Johnson, New Brunswick, NJ, USA) associated with high mortality. At present, there are no known differences in the pathophysiology or risk factors of VITT with the AstraZeneca vaccine (ChAdOx1) compared with the Johnson & Johnson vaccine (AD26.COV2.S). Herein, we present the case of a healthy 39-year-old patient with VITT after having received the vaccine Ad26.COV2.S. Ten days after vaccination, the patient developed a deep vein thrombosis and subsequent pulmonary embolism. A computed tomography scan of the abdomen showed adrenal gland bleeding and an adrenocorticotrophic hormone stimulation test diagnosed adrenal insufficiency. Therapy with intravenous immunoglobulin, argatroban and hydrocortisone was initiated immediately after diagnosis. The patient left the hospital 22 days after admission with the diagnosis of adrenal insufficiency but otherwise in good health. To the best of our knowledge, five cases of VITT and adrenal bleeding have been described to date in the literature but the presented case was the first to occur after immunisation with the vaccine of Johnson & Johnson. In summary, VITT-associated adrenal dysfunction is a very rare complication of vaccination with an adenoviral vector-based COVID-19 vaccine.

COVID-19 and Vaccine-Induced Thrombosis

Coronavirus disease 2019 (COVID-19), a highly contagious infectious disease, has had a catastrophic effect on the world's demographics resulting in more than 2.9 million deaths worldwide till January 2021. It can lead to systemic multi-organ complications; in particular, venous and arterial thromboembolism risk is significantly increased. Venous thromboembolism (VTE) occurs in 22.7% of patients with COVID-19 in the ICU and 8% in non-ICU hospitalized patients. Studies evaluating thromboprophylaxis strategies in patients with COVID-19 are needed to improve the prevention of VTE. VTE is the most commonly reported thrombotic complication, with higher incidence rates among critically ill patients. Several vaccines have been licensed and are currently used to combat the COVID-19 pandemic. Also, several cases of vaccine-induced thrombosis have been reported. Vaccination remains the most critical measure to curb the COVID-19 pandemic. There is a broad consensus that the benefits of vaccination greatly outweigh the potential risks of rare vaccine side effects, such as vaccine-induced immune thrombotic thrombocytopenia (VITT). Therefore, the importance of vaccination should be emphasized. This statement aims to focus on VITT.

Epidemiology of VITT

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a life-threatening syndrome of aggressive thrombosis, often profound thrombocytopenia, and frequently overt disseminated intravascular coagulation. It has been associated with 2 adenovirus vector COVID-19 vaccines: ChAdOx1 nCoV-19 (AstraZeneca) and Ad26.COV2.S (Janssen). Unlike the myriad of other conditions that cause thrombosis and thrombocytopenia, VITT has an important distinguishing feature: affected individuals have platelet activating anti-PF4 antibodies that appear in a predictable time frame following vaccination. The reported incidence of VITT differs between jurisdictions; it is dependent on accurate ascertainment of cases and accurate estimates of the size of the vaccinated population. The incidence ranges from 1 case per 26,500 to 127,3000 first doses of ChAdOx1 nCoV-19 administered. It is estimated at 1 case per 518,181 second doses of ChAdOx1 nCoV-19 administered, and 1 case per 263,000 Ad26.COV2.S doses administered. There are no clear risk factors for VITT, including sex, age, or comorbidities. VITT is a rare event, but its considerable morbidity and mortality merit ongoing pharmacovigilance, and accurate case ascertainment.

Coagulopathy and Fibrinolytic Pathophysiology in COVID-19 and SARS-CoV-2 Vaccination

Coronavirus Disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and is frequently complicated by thrombosis. In some cases of severe COVID-19, fibrinolysis may be markedly enhanced within a few days, resulting in fatal bleeding. In the treatment of COVID-19, attention should be paid to both coagulation activation and fibrinolytic activation. Various thromboses are known to occur after vaccination with SARS-CoV-2 vaccines. Vaccine-induced immune thrombotic thrombocytopenia (VITT) can occur after adenovirus-vectored vaccination, and is characterized by the detection of anti-platelet factor 4 antibodies by enzyme-linked immunosorbent assay and thrombosis in unusual locations such as cerebral venous sinuses and visceral veins. Treatment comprises high-dose immunoglobulin, argatroban, and fondaparinux. Some VITT cases show marked decreases in fibrinogen and platelets and marked increases in D-dimer, suggesting the presence of enhanced-fibrinolytic-type disseminated intravascular coagulation with a high risk of bleeding. In the treatment of VITT, evaluation of both coagulation activation and fibrinolytic activation is important, adjusting treatments accordingly to improve outcomes.

Patients With Suspected Severe Adverse Reactions to COVID-19 Vaccination Admitted to Intensive Care Unit: A Case Report

Background

Several cases of adverse reactions following vaccination for coronavirus disease 2019 (COVID-19) with adenoviral vector vaccines or mRNA-based vaccines have been reported to date. The underlying syndrome has been named “vaccine-induced immune thrombotic thrombocytopenia” (VITT) or “thrombosis with thrombocytopenia syndrome (TTS)” with different clinical manifestations.

Methods

We report the clinical course of five patients who had severe adverse reactions to COVID-19 vaccines, either with VITT/TTS, abdominal or pulmonary thrombosis after adenoviral vaccines, or Stevens' Johnson syndrome because of mRNA vaccination, all of whom required admission to the intensive care unit (ICU).

Conclusions

All patients with severe or life-threatening suspected reaction to different types of COVID-19 vaccination required ICU admission. A prompt evaluation of early symptoms and individualized clinical management is needed to improve outcomes.

Clinical Care Pathway for Suspected Vaccine-Induced Immune Thrombotic Thrombocytopenia After ChAdOx1 nCoV-19 vaccination

A clinical care pathway using centralized PF4-ELISA testing detected a 37% prevalence of thrombosis among patients investigated for VITT.

VITT should be confirmed by PF4-ELISA as thrombosis with thrombocytopenia can occur without PF4 antibodies after SARS-CoV-2 vaccination.

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare complication after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) adenoviral vector vaccination. In British Columbia (BC), Canada, a provincial clinical care pathway was developed to guide clinicians in evaluating for VITT among patients who present with thrombocytopenia or thrombosis symptoms within 4 to 28 days after adenoviral vector vaccine exposure. All patients had enzyme-linked immunosorbent assay (ELISA) testing for platelet factor 4 (PF4) antibodies, and all cases with positive PF4-ELISA or d-dimer levels ≥2.0 mg/L fibrinogen equivalent units (FEU) had further testing for platelet-activating PF4 antibodies using a modified serotonin release assay (SRA). Between 1 May and 30 June 2021, 37% of 68 patients investigated for VITT had thrombosis, but only 3 had VITT confirmed by PF4-ELISA and SRA. Platelet counts, d-dimer levels, and ELISA optical density values were significantly different between those with and without VITT. Three patients had thrombocytopenia and thrombosis with d-dimer levels >4.0 mg/L FEU but had negative PF4-ELISA and SRA results. Patients with VITT were treated successfully with IV immunoglobulin, nonheparin anticoagulants, and corticosteroids. Our pathway demonstrated that thrombosis is common among patients investigated for VITT and that PF4-ELISA testing is necessary to confirm VITT in those presenting with thrombosis and thrombocytopenia.

Experience of danaparoid to treat vaccine-induced immune thrombocytopenia and thrombosis, VITT

BACKGROUND

Vaccine-induced immune thrombocytopenia and thrombosis (VITT) is triggered by nCOV-19 adenovirus-vectored vaccines against SARS-CoV2. Pathogenesis has been mainly related to platelet activation via PF4-reactive antibodies that activate platelets and may cross-react with heparin. Data concerning optimal anticoagulation are anecdotal, and so far, there are scattered reports of danaparoid use in VITT management. Danaparoid has good efficacy and safety in treatment of heparin-induced thrombocytopenia. We report here our experience of the administration and monitoring danaparoid in VITT.

METHODS

We diagnosed a series of six hospitalized cases of VITT, based on the international diagnostic guidance. All VITT-related data were from the local electronic medical and laboratory record system and were analyzed with IBM SPSS Statistics.

RESULTS

Predominately women in their late 40's developed VITT on average 24 days (range 9-59) after the first ChAdOx1 dose. Clinical presentation included single or multiple venous and/or arterial thrombosis, moderate thrombocytopenia and high D-dimer levels. After detecting PF4 antibodies subcutaneous danaparoid was our first-line antithrombotic treatment with an average duration of three weeks. The median plasma anti-FXa activity was in the lower part of the therapeutic range and during the first week of danaparoid administration clinical symptoms, platelet counts, and fibrin turnover resolved or significantly improved. The average duration of hospital admission was 10 days [2-18]. One patient died but the other five patients recovered completely.

CONCLUSIONS

The clinical outcomes of our small cohort align with the earlier published reports, and support danaparoid as a rational option for the initial anticoagulation of VITT patients.

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.

Thrombocytopenia in COVID‑19 and vaccine‑induced thrombotic thrombocytopenia

The highly heterogeneous symptomatology and unpredictable progress of COVID-19 triggered unprecedented intensive biomedical research and a number of clinical research projects. Although the pathophysiology of the disease is being progressively clarified, its complexity remains vast. Moreover, some extremely infrequent cases of thrombotic thrombocytopenia following vaccination against SARS-CoV-2 infection have been observed. The present study aimed to map the signaling pathways of thrombocytopenia implicated in COVID-19, as well as in vaccine-induced thrombotic thrombocytopenia (VITT). The biomedical literature database, MEDLINE/PubMed, was thoroughly searched using artificial intelligence techniques for the semantic relations among the top 50 similar words (>0.9) implicated in COVID-19-mediated human infection or VITT. Additionally, STRING, a database of primary and predicted associations among genes and proteins (collected from diverse resources, such as documented pathway knowledge, high-throughput experimental studies, cross-species extrapolated information, automated text mining results, computationally predicted interactions, etc.), was employed, with the confidence threshold set at 0.7. In addition, two interactomes were constructed: i) A network including 119 and 56 nodes relevant to COVID-19 and thrombocytopenia, respectively; and ii) a second network containing 60 nodes relevant to VITT. Although thrombocytopenia is a dominant morbidity in both entities, three nodes were observed that corresponded to genes (AURKA, CD46 and CD19) expressed only in VITT, whilst ADAM10, CDC20, SHC1 and STXBP2 are silenced in VITT, but are commonly expressed in both COVID-19 and thrombocytopenia. The calculated average node degree was immense (11.9 in COVID-19 and 6.43 in VITT), illustrating the complexity of COVID-19 and VITT pathologies and confirming the importance of cytokines, as well as of pathways activated following hypoxic events. In addition, PYCARD, NLP3 and P2RX7 are key potential therapeutic targets for all three morbid entities, meriting further research. This interactome was based on wild-type genes, revealing the predisposition of the body to hypoxia-induced thrombosis, leading to the acute COVID-19 phenotype, the 'long-COVID syndrome', and/or VITT. Thus, common nodes appear to be key players in illness prevention, progression and treatment.

Treatment for Immune Thrombocytopenia in Coronavirus Disease 2019 (COVID-19) Infection after COVID-19 Vaccination: A Case Report

Thrombocytopenia is one of the rare signs of both the coronavirus disease 2019 (COVID-19) and COVID-19 vaccination. An 85-year-old man was diagnosed with immune thrombocytopenia and COVID-19, 7 days after COVID-19 vaccination. The patient was successfully treated with a short course of intravenous immunoglobulin and oral corticosteroids.

COVID-19 Vaccine-Induced Immune Thrombotic Thrombocytopenia (VITT) and Cerebral Venous Sinus Thrombosis (CVST)- Lessons for India

The COVID-19 pandemic evolved rapidly, overwhelming health care systems around the world. The cost to life and socioeconomic burden prompted a search for new treatments and vaccines. Several collaborations developed and could deliver state-of-the-art vaccines with acceptable efficacy and safety in record time. Recently, vaccination with Oxford-AstraZeneca and Johnson and Johnson vaccines was halted due to the reported adverse effects of vaccine-induced immune thrombotic thrombocytopenia (VITT) and cerebral venous sinus thrombosis (CVST). Although a detailed risk-benefit analysis led to their reinstitution, physicians across the world are still trying to understand the pathophysiology and mechanisms of these neurological adverse effects in order to better identify, diagnose, and treat them. One of the mechanisms that have been implicated is related to the adenovirus-based vector of these vaccines. COVISHIELD, which is the most widely administered vaccine in India, also shares the same vector. As India enters the next phase of vaccine distribution for younger adults, there are chances that such adverse effects may emerge. In this review, we analyze the temporary suspension of the administration of the vaccines due to VITT/CVST, summarize the existing guidelines about diagnosis and treatment of these neurological disorders as well as the need for increasing pharmacovigilance and awareness among physicians. Screening for potential risk factors, avoiding aggravating factors like dehydration, and providing choices in vaccinating the high-risk populations could help in avoiding these rare but potentially fatal adverse outcome.

Recognizing Vaccine-Induced Immune Thrombotic Thrombocytopenia

OBJECTIVES

Vaccine-induced immune thrombotic thrombocytopenia is an unexpected consequence of the coronavirus disease 2019 pandemic era. We reviewed the pathogenesis, clinical presentation, diagnosis, and treatment of this rare side effect.

DATA SOURCES

Online search of published medical literature through PubMed, Scopus, Web of Science, and Google Scholar using the terms "COVID-19," "vaccine," "thrombosis" was performed.

STUDY SELECTION

Articles were chosen for inclusion based on their relevance to coronavirus disease 2019, vaccine, and thrombosis.

DATA SYNTHESIS

Vaccine-induced immune thrombotic thrombocytopenia manifests most often as unusual thromboses (cerebral venous sinus thrombosis, splanchnic vein thrombosis) but sometimes also "usual" thromboses (arterial stroke, pulmonary embolism, deep-vein thrombosis), with oftentimes severe thrombocytopenia, that becomes clinically evident 5-30 days after adenovirus-vectored coronavirus disease 2019 vaccine administration. Most patients have disseminated intravascular coagulation. These features are the result of vaccine-triggered formation of anti-platelet factor 4 immunoglobulin G that activate platelets, clinically mimicking autoimmune heparin-induced thrombocytopenia. Early recognition based on thrombosis (sometimes, hemorrhage), thrombocytopenia, and d-dimer elevation within the day 5-30 postvaccine "window" is important given treatment with high-dose IV immunoglobulin plus nonheparin anticoagulation.

CONCLUSIONS

Vaccine-induced immune thrombotic thrombocytopenia is a serious complication of vaccination that is not feasible to anticipate or prevent. When the patient presents with sustained headache, neurologic symptoms/signs, abdominal pain, dyspnea, or limb pain/swelling beginning 5-30 days post vaccination, platelet count and d-dimer must be measured, and imaging for thrombosis performed. Confirmation of vaccine-induced immune thrombotic thrombocytopenia diagnosis should be ordered (platelet factor 4/polyanion enzyme-linked immunosorbent assay; platelet factor 4-enhanced platelet activation testing) as treatment is initiated (nonheparin anticoagulation, IV immunoglobulin).

New-onset autoimmune phenomena post COVID-19 vaccination

Coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to an unprecedented setback for global economy and health. Vaccination is one of the most effective intervention to substantially reduce severe disease and death due to SARS-CoV-2 infection. Vaccination programs are being rolled out globally, but most of these vaccines have been approved without extensive studies on their side effects and efficacy. Recently, new-onset autoimmune phenomena after COVID-19 vaccination have been reported increasingly (e.g., immune thrombotic thrombocytopenia, autoimmune liver diseases, Guillain-Barré syndrome, IgA nephropathy, rheumatoid arthritis and systemic lupus erythematosus, etc.). Molecular mimicry, the production of particular autoantibodies and the role of certain vaccine adjuvants seem to be substantial contributors to autoimmune phenomena. However, whether the association between COVID-19 vaccine and autoimmune manifestations is coincidental or causal remains to be elucidated. Here, we summarize the emerging evidence about autoimmune manifestations occurring in response to certain COVID-19 vaccines. Although information pertaining to the risk of autoimmune disease as a consequence of vaccination is controversial, we merely propose our current understanding of autoimmune manifestations associated with COVID-19 vaccine. In fact, we do not aim to disavow the overwhelming benefits of mass COVID-19 vaccination in preventing COVID-19 morbidity and mortality. These reports could help guide clinical assessment and management of autoimmune manifestations after COVID-19 vaccination.

Clinical significance of hepatosplenic thrombosis in vaccine-induced immune thrombotic thrombocytopenia after ChAdOx1 nCoV-19 vaccination

BACKGROUND

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare, serious complication after adenoviral COVID-19 vaccine administration that can involve various organ systems. We aimed to investigate the clinical significance of hepatosplenic thrombosis in patients with VITT.

METHODS

We searched PubMed ePubs, Scopus, Embase, and Web of Science databases for studies published until April 28, 2021 involving patients with VITT after ChAdOx1 nCoV-19 vaccination. Demographic and clinical characteristics including laboratory measurements were collected and compared.

RESULTS

Four case series and three case reports involving 48 cases of VITT were included. Hepatosplenic thrombosis was present in eight cases (17%). Patients with hepatosplenic thrombosis had lower platelet counts (13,000 vs. 29,500/μL, p=0.016) and higher D-dimer levels (140.0 vs. 57.3 times upper limit of normal range, p=0.028). Multiple-site thrombosis was also associated with hepatosplenic thrombosis (88% vs. 15%, p<0.001).

CONCLUSIONS

This is the first study comparing clinical profiles of patients with VITT according to the presence of hepatosplenic thrombosis. Patients with hepatosplenic thrombosis had more severe presentations with lower platelet counts, higher D-dimer levels, and higher rate of multiple-site thromboses. Further studies with larger sample sizes are required to establish definitive evidence regarding the significance of hepatosplenic thrombosis in VITT.

Management of Vascular Thrombosis in Patients with Thrombocytopenia

Platelets play critical roles in hemostasis and thrombosis. While low platelet counts increase the risk of bleeding, antithrombotic drugs, including anticoagulants and antiplatelet agents, are used to treat thromboembolic events. Thus, the management of thrombosis in patients with low platelet counts is challenging with hardly any evidence available to guide treatment. Recognition of the underlying cause of thrombocytopenia is essential for assessing the bleeding risk and tailoring therapeutic options. A typical clinical scenario is the occurrence of venous thromboembolism (VTE) in cancer patients experiencing transient thrombocytopenia during myelosuppressive chemotherapy. In such patients, the severity of thrombocytopenia, thrombus burden, clinical symptoms, and the timing of VTE relative to thrombocytopenia must be considered. In clinical practice, distinct hematological disorders characterized by low platelet counts and a thrombogenic state require specific diagnostics and treatment. These include the antiphospholipid syndrome, heparin-induced thrombocytopenia (HIT) and (spontaneous) HIT syndromes, disseminated intravascular coagulation, and paroxysmal nocturnal hemoglobinuria.

Innovative vaccine platforms against infectious diseases: Under the scope of the COVID-19 pandemic

While classic vaccines have proved greatly efficacious in eliminating serious infectious diseases, innovative vaccine platforms open a new pathway to overcome dangerous pandemics via the development of safe and effective formulations. Such platforms play a key role either as antigen delivery systems or as immune-stimulators that induce both innate and adaptive immune responses. Liposomes or lipid nanoparticles, virus-like particles, nanoemulsions, polymeric or inorganic nanoparticles, as well as viral vectors, all belong to the nanoscale and are the main categories of innovative vaccines that are currently on the market or in clinical and preclinical phases. In this paper, we review the above formulations used in vaccinology and we discuss their connection with the development of safe and effective prophylactic vaccines against SARS-CoV-2.

Vaccine-induced thrombosis and thrombocytopenia (VITT) in Ireland: A review of cases and current practices

Since the beginning of the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS CoV-2) virus pandemic, several highly effective and safe vaccines have been produced at remarkable speed. Following global implementation of vaccination programmes, cases of thrombosis with thrombocytopenia following administration of adenoviral vector-based vaccines started being reported. In this review we discuss the known pathogenesis and epidemiology of so-called vaccine induced thrombocytopenia and thrombosis (VITT). We consider the available guidelines, diagnostic laboratory tests and management options for these patients. Finally, we discuss important unanswered questions and areas for future research in this novel pathoclinical entity.

COVID-19 coagulopathies: Human blood proteins mimic SARS-CoV-2 virus, vaccine proteins and bacterial co-infections inducing autoimmunity: Combinations of bacteria and SARS-CoV-2 synergize to induce autoantibodies targeting cardiolipin, cardiolipin-binding proteins, platelet factor 4, prothrombin, and coagulation factors

Severe COVID-19 is often accompanied by coagulopathies such as thrombocytopenia and abnormal clotting. Rarely, such complications follow SARS-CoV-2 vaccination. The cause of these coagulopathies is unknown. It is hypothesized that coagulopathies accompanying SARS-CoV-2 infections and vaccinations result from bacterial co-infections that synergize with virus-induced autoimmunity due to antigenic mimicry of blood proteins by both bacterial and viral antigens. Coagulopathies occur mainly in severe COVID-19 characterized by bacterial co-infections with Streptococci, Staphylococci, Klebsiella, Escherichia coli, and Acinetobacter baumannii. These bacteria express unusually large numbers of antigens mimicking human blood antigens, as do both SARS-CoV-2 and adenoviruses. Bacteria mimic cardiolipin, prothrombin, albumin, and platelet factor 4 (PF4). SARS-CoV-2 mimics complement factors, Rh antigens, platelet phosphodiesterases, Factors IX and X, von Willebrand Factor (VWF), and VWF protease ADAMTS13. Adenoviruses mimic prothrombin and platelet factor 4. Bacterial prophylaxis, avoidance of vaccinating bacterially infected individuals, and antigen deletion for vaccines may reduce coagulopathy risk. Also see the video abstract here: https://youtu.be/zWDOsghrPg8.

VITT following Ad26.COV2.S vaccination presenting without radiographically demonstrable thrombosis

We report a case of VITT following Ad26.COV2.S COVID-19 vaccination without radiographically demonstrable thrombosis at presentation.

Early VITT recognition and treatment with nonheparin anticoagulation can prevent severe thrombotic complications.

We report a case of vaccine-induced immune thrombotic thrombocytopenia (VITT) in a young man diagnosed 13 days after Ad26.COV2.S COVID-19 (Johnson & Johnson/Janssen) vaccination. He presented to us with 5 days of progressive left leg pain, thrombocytopenia, hypofibrinogenemia, and markedly elevated d-dimers, but without radiographically demonstrable thrombosis. Despite negative imaging, we initiated treatment of presumptive VITT given the striking clinical picture that included the timing of his recent adenovirus-based COVID-19 vaccine, leg symptoms, marked thrombocytopenia, and consumptive coagulopathy. He received intravenous immune globulin, prednisone, and argatroban and was discharged 7 days later much improved. His positive platelet factor 4 enzyme-linked immunosorbent assay antibody test returned after treatment was initiated. To our knowledge, this is the first reported case of VITT following Ad26.COV2.S vaccination presenting without radiographically demonstrable thrombosis. Our patient highlights the importance of knowing vaccine status and initiating treatment as soon as possible in the right clinical setting, even in the absence of radiographic evidence of thrombus. Early VITT recognition and treatment provide an opportunity to prevent serious thrombotic complications.

Nano-carriers of COVID-19 vaccines: the main pillars of efficacy

As the current COVID-19 pandemic illustrates, vaccination is the most powerful method of disease prevention and public confidence in vaccines depends on their safety and efficacy. The information gathered in the current pandemic is growing at an accelerated pace. Both the key vital protein DNA/RNA messengers and the delivery carriers are the elements of a puzzle including their interactions with the immune system to suppress SARS-CoV-2 infection. A new nano-era is beginning in the vaccine development field and an array of side applications for diagnostic and antiviral tools will likely emerge. This review focuses on the evolution of vaccine carriers up to COVID-19-aimed nanoparticles and the immune-related adverse effects imposed by these nanocarriers.

Autoimmunity roots of the thrombotic events after COVID-19 vaccination

Although vaccination represents the most promising way to stop or contain the coronavirus disease 2019 (COVID-19) pandemic and safety and effectiveness of available vaccines were proven, a small number of individuals who received anti-SARS-CoV-2 vaccines developed a prothrombotic syndrome. Vaccine-induced immune thrombotic thrombocytopenia (VITT) can be triggered by the adenoviral vector-based vaccine, whereas lipid nanoparticle-mRNA-based vaccines can induce rare cases of deep vein thrombosis (DVT). Although the main pathogenic mechanisms behind this rare phenomenon have not yet been identified, both host and vaccine factors might be involved, with pathology at least in part being related to the vaccine-triggered autoimmune reaction. In this review, we are considering some aspects related to pathogenesis, major risk factors, as well as peculiarities of diagnosis and treatment of this rare condition.

Long-term follow-up after successful treatment of vaccine-induced prothrombotic immune thrombocytopenia

BACKGROUND

Cases of ChAdOx1 nCoV-19 (AstraZeneca) vaccinated patients with thrombocytopenia, elevated D-dimer, and elevated platelet factor 4 (PF4) antibody levels with- and without thrombosis have been reported. No recommendations regarding the duration of anticoagulation have been made, because data on the long-term course beyond the first weeks is lacking.

OBJECTIVE

To report on the treatment, medical course, and longitudinal follow-up of laboratory parameters in patients with vaccine-induced prothrombotic immune thrombocytopenia (VIPIT).

PATIENTS

We followed VIPIT patients with- (n = 3) and without (n = 3) venous thromboembolism fulfilling the aforementioned laboratory criteria.

RESULTS

Elevated D-dimer (median: 35.10 μg/ml, range: 17.80-52.70), thrombocytopenia (42 G/l, 20-101), and strong positivity in the platelet factor 4 (PF4)/heparin-enzyme-immunoassay (2.42 optical density [OD], 2.06-3.13; reference range < 0.50) were present in all patients after vaccination (10 days, 7-17). Routine laboratory parameters rapidly improved upon initiation of treatment (comprising therapeutic non-heparin anticoagulation in all patients and high dose immunoglobulins ± corticosteroids in 5 patients). PF4 antibody levels slowly decreased over several weeks. Patients were discharged in good physical health (8 days, 5-13). VIPIT did not recur during follow-up (12 weeks, 8-17). Five of 6 patients fully recovered (in 2 patients thrombosis had resolved, in 1 patient exertional dyspnea persisted).

CONCLUSIONS

Remissions without sequelae can be achieved upon rapid initiation of treatment in patients with VIPIT. Platelet factor 4 antibody levels slowly decreased over several weeks but VIPIT did not recur in any of our patients. Continuation of anticoagulation in VIPIT patients at least until PF4 antibody negativity is reached seems reasonable.