SARS-CoV-2 vaccine-induced immune thrombotic thrombocytopenia

Cranioplasty after Decompressive Craniectomy (DC) in a Patient with Intracerebral Hemorrhage after SARS-CoV-2 Vaccination-Related Vaccine-Induced Thrombotic Thrombocytopenia (VITT)-Proposal of a Management Protocol for This Rare Pathological Condition

The COVID-19 (coronavirus disease) pandemic had a severe impact on public health worldwide. A rare but serious complication after administration of adenoviral vaccines against SARS-CoV-2 (AstraZeneca-Oxford and Johnson & Johnson) is vaccine-induced immune thrombotic thrombocytopenia and thrombosis (VITT), which can lead to serious complications such as cerebral venous sinus thrombosis (CVST). CVST itself can cause subarachnoid hemorrhage (SAH) and/or intracerebral hemorrhage (ICH), leading to high mortality due to herniation of brain parenchyma. In those patients, an emergent decompressive hemicraniectomy (DC) is regularly performed. Herein, the authors want to focus on the patients who survive DC following VITT-associated CVST and shed light on the neurosurgical considerations in those patients. We herein propose a treatment algorithm regarding the timing and the perioperative management of cranioplasty. We describe an exemplary case highlighting that special circumstances may result in a more urgent need for autologous cranioplasty than usual, based on individual risk assessment.

The onset of de novo autoantibodies in healthcare workers after mRNA based anti-SARS-CoV-2 vaccines: a single centre prospective follow-up study

Nowadays, data concerning the risk of autoimmune disease after SARS-CoV-2 (COVID-19) vaccination is controversial. The aim of this single centre prospective follow-up study was to evaluate whether healthcare workers (HCWs) vaccinated with BNT162b2 mRNA and mRNA-1273 will show a development and/or a persistence of autoantibodies, focussing on the detection of antibodies against nuclear antigens (antinuclear antibodies, ANA). We enrolled 155 HCWs, however only 108 of them received the third dose and were considered for further analysis. Blood samples were collected before vaccine inoculation (T0), at 3 (T1) and 12 months (T2) after the first dose. All samples were analysed for the presence of a) ANA using indirect Immunofluorescence [IIF] (dilutions of 1:80, 1:160. 1:320 and 1:640), and anti-smooth muscle antibodies (ASMA); b) anti-myeloperoxidase (anti-MPO), anti-proteinase 3 (anti-PR3) and anti-citrullinated peptide antibodies (aCCP) [FEIA]; c) anti-phospholipid antibodies (anticardiolipin [aCL], anti-beta-2- glycoprotein I [anti-ß-2GPI] (Chemiluminescence). Line-blot technology was performed using the following kit: EUROLINE ANA profile 3 plus DFS70 (IgG). Our research suggests that mRNA based anti-SARSCoV-2 vaccines can induce the production of de novo ANA in 22/77(28,57%) of subjects and that the percentage of positivity seems to be directly correlated to the number of vaccine expositions: 6/77 (7,79%) after 2 doses; 16/77 (20,78%) after 3 doses. Since it is known that hyperstimulation of the immune system could lead to autoimmunity, these preliminary results seem to further sustain the idea that the hyperstimulation of the immune system might lead to an autoinflammatory mechanism and eventually to autoimmune disorders. However, the link between SARS-CoV-2 vaccination and the development of autoimmune diseases needs to be further investigated.

Recommendations on the Management of Patients with Immune Thrombocytopenia (ITP) in the Context of SARS-CoV-2 Infection and Vaccination: Consensus Guidelines from a Spanish ITP Expert Group

Primary immune thrombocytopenia (ITP) is an acquired autoimmune disease with highly variable presentation, characteristics, and clinical course. Thrombocytopenia is a common complication of many viral infections, including SARS-CoV-2. In addition, both de novo ITP and exacerbation of ITP after vaccination against SARS-CoV-2 have been reported. Patients infected with SARS-CoV-2 develop a prothrombotic coagulopathy called COVID-19-associated coagulopathy (CAC). In addition, autoimmune hematological disorders secondary to SARS-CoV-2 infection, mainly ITP and autoimmune hemolytic anemia (AIHA), have been described. Furthermore, SARS-CoV-2 infection has been associated with exacerbation of autoimmune processes, including ITP. In fact, there is evidence of a high relapse rate in patients with preexisting ITP and COVID-19. As for vaccination against SARS-CoV-2, hematological adverse events (HAE) are practically anecdotal. The most common HAE is thrombocytopenia-associated thrombosis syndrome (TTS) linked to vectored virus vaccines. Other HAEs are very rare, but should be considered in patients with previous complement activation disease or autoimmunity. In patients with ITP who are vaccinated against SARS-CoV-2, the main complication is exacerbation of ITP and the bleeding that may result. In fact, this complication occurs in 12% of patients, with splenectomized and refractory patients with more than five lines of previous treatment and platelet counts below 50 × 10⁹/L being the most vulnerable. We conclude that, in general, there is no greater risk of severe SARS-CoV-2 infection in ITP patients than in the general population. Furthermore, no changes are advised in patients with stable ITP, the use of immunosuppressants is discouraged unless there is no other therapeutic option, and patients with ITP are not contraindicated for vaccination against COVID-19.

Tissue factor in COVID-19-associated coagulopathy

Evidence of micro- and macro-thrombi in the arteries and veins of critically ill COVID-19 patients and in autopsies highlight the occurrence of COVID-19-associated coagulopathy (CAC). Clinical findings of critically ill COVID-19 patients point to various mechanisms for CAC; however, the definitive underlying cause is unclear. Multiple factors may contribute to the prothrombotic state in patients with COVID-19. Aberrant expression of tissue factor (TF), an initiator of the extrinsic coagulation pathway, leads to thrombotic complications during injury, inflammation, and infections. Clinical evidence suggests that TF-dependent coagulation activation likely plays a role in CAC. Multiple factors could trigger abnormal TF expression and coagulation activation in patients with severe COVID-19 infection. Proinflammatory cytokines that are highly elevated in COVID-19 (IL-1β, IL-6 and TNF-α) are known induce TF expression on leukocytes (e.g. monocytes, macrophages) and non-immune cells (e.g. endothelium, epithelium) in other conditions. Antiphospholipid antibodies, TF-positive extracellular vesicles, pattern recognition receptor (PRR) pathways and complement activation are all candidate factors that could trigger TF-dependent procoagulant activity. In addition, coagulation factors, such as thrombin, may further potentiate the induction of TF via protease-activated receptors on cells. In this systematic review, with other viral infections, we discuss potential mechanisms and cell-type-specific expressions of TF during SARS-CoV-2 infection and its role in the development of CAC.

COVID-19 and antiphospholipid antibodies

Antiphospholipid syndrome and the coagulopathy of COVID-19 share many pathophysiologic features, including endotheliopathy, hypercoagulability, and activation of platelets, complement pathways, and neutrophil extracellular traps, all acting in concert via a model of immunothrombosis. Antiphospholipid antibody production in COVID-19 is common, with 50% of COVID-19 patients being positive for lupus anticoagulant in some studies, and with non-Sapporo criteria antiphospholipid antibodies being prevalent as well. The biological significance of antiphospholipid antibodies in COVID-19 is uncertain, as such antibodies are usually transient, and studies examining clinical outcomes in COVID-19 patients with and without antiphospholipid antibodies have yielded conflicting results. In this review, we explore the biology of antiphospholipid antibodies in COVID-19 and other infections and discuss mechanisms of thrombogenesis in antiphospholipid syndrome and parallels with COVID-19 coagulopathy. In addition, we review the existing literature on safety of COVID-19 vaccination in patients with antiphospholipid antibodies and antiphospholipid syndrome.

Adverse Events Associated with BNT162b2 and AZD1222 Vaccines in the Real World: Surveillance Report in a Single Italian Vaccine Center

Aim: Despite huge efforts in developing specific drugs, vaccination represents the only effective strategy against COVID-19. Efficacy and safety of the COVID-19 vaccines were established during clinical trials. Nonetheless, it is very important to perform continuous surveillance. This observational study aimed to report potential Adverse Events Following Immunization (AEFI) following the first dose of two different COVID-19 vaccines, BNT162b2 and AZD1222. Methods and Results: Subjects who underwent vaccination at the vaccine center of the University Hospital of Salerno, Italy, were interviewed using an ad hoc questionnaire. AZD-vac group (n = 175) who received AZD1222 had a higher number of AEFI than the BNT-vac group (n = 1613) who received BNT162b2 (83% vs. 42%). The most frequent AEFI associated with AZD1222 and BNT162b2 were fever and pain at the injection site, respectively. The AZD-vac group used drugs to contrast AEFI more frequently than the BNT-vac group. In the BNT-vac group, there was a higher incidence of AEFI in women than in men (26.2% vs. 15.8%, p = 0.01), while no gender-related difference was observed in the AZD-vac group. Conclusions: AZD1222 and BNT162b2 vaccines show a good safety profile. Based on our results and literature data, there are no reasons to justify the reluctance that persists towards immunization.

Prothrombotic Phenotype in COVID-19: Focus on Platelets

COVID-19 infection is associated with a broad spectrum of presentations, but alveolar capillary microthrombi have been described as a common finding in COVID-19 patients, appearing as a consequence of a severe endothelial injury with endothelial cell membrane disruption. These observations clearly point to the identification of a COVID-19-associated coagulopathy, which may contribute to thrombosis, multi-organ damage, and cause of severity and fatality. One significant finding that emerges in prothrombotic abnormalities observed in COVID-19 patients is that the coagulation alterations are mainly mediated by the activation of platelets and intrinsically related to viral-mediated endothelial inflammation. Beyond the well-known role in hemostasis, the ability of platelets to also release various potent cytokines and chemokines has elevated these small cells from simple cell fragments to crucial modulators in the blood, including their inflammatory functions, that have a large influence on the immune response during infectious disease. Indeed, platelets are involved in the pathogenesis of acute lung injury also by promoting NET formation and affecting vascular permeability. Specifically, the deposition by activated platelets of the chemokine platelet factor 4 at sites of inflammation promotes adhesion of neutrophils on endothelial cells and thrombogenesis, and it seems deeply involved in the phenomenon of vaccine-induced thrombocytopenia and thrombosis. Importantly, the hyperactivated platelet phenotype along with evidence of cytokine storm, high levels of P-selectin, D-dimer, and, on the other hand, decreased levels of fibrinogen, von Willebrand factor, and thrombocytopenia may be considered suitable biomarkers that distinguish the late stage of COVID-19 progression in critically ill patients.