An Update on COVID-19 Vaccine Induced Thrombotic Thrombocytopenia Syndrome and Some Management Recommendations

Abstract

The thrombotic thrombocytopenia syndrome (TTS), a complication of COVID-19 vaccines, involves thrombosis (often cerebral venous sinus thrombosis) and thrombocytopenia with occasional pulmonary embolism and arterial ischemia. TTS appears to mostly affect females aged between 20 and 50 years old, with no predisposing risk factors conclusively identified so far. Cases are characterized by thrombocytopenia, higher levels of D-dimers than commonly observed in venous thromboembolic events, inexplicably low fibrinogen levels and worsening thrombosis. Hyper fibrinolysis associated with bleeding can also occur. Antibodies that bind platelet factor 4, similar to those associated with heparin-induced thrombocytopenia, have also been identified but in the absence of patient exposure to heparin treatment. A number of countries have now suspended the use of adenovirus-vectored vaccines for younger individuals. The prevailing opinion of most experts is that the risk of developing COVID-19 disease, including thrombosis, far exceeds the extremely low risk of TTS associated with highly efficacious vaccines. Mass vaccination should continue but with caution. Vaccines that are more likely to cause TTS (e.g., Vaxzevria manufactured by AstraZeneca) should be avoided in younger patients for whom an alternative vaccine is available.

Stroke Associated with COVID-19 Vaccines

“…Immune globulin prevents antibody-mediated platelet clearance and may down-regulate platelet activation by immune complexes by blocking platelet FcRγIIA receptors (127). Therefore, prompt initiation of IVIg (1g/kg over two days if needed) that is likely to influence the disease process, regardless of the severity of thrombocytopenia, and continuing to review the clinical course, is recommended for VITT (128). Contrastingly, clinicians should avoid all forms of heparin (i.e.…”

“…Severe bleeding and/or the need for surgical intervention may favor platelet transfusion following the initiation of IVIg, non-heparin anti-coagulation, and fibrinogen replacement if its level is less than 1.5 g/L (116,117). Platelet transfusion should be considered in life-threatening bleeding situations (128). In other words, platelet transfusion is an optional treatment to support anticoagulation, and its superiority to critical care by argatroban (low dose) without platelet transfusion has not yet been confirmed (116,117).…”

Eruptive Angiomatosis Triggered by COVID-19 Vaccination

“…Mohta et al have reported 12 cases of eruptive pseudoangiomatosis, a similar vascular lesion that commonly occurs in the pediatric age group and is associated with ChAdOx1 nCoV-19 coronavirus vaccine (recombinant) in India [7]. The possible vascular injury [8,9] or immune dysregulation [10] caused by the COVID-19 vaccination could play a role in the development of these eruptive vascular lesions.…”

COVID-19, neurovascular thrombotic problem and short summary on blood coagulation disorder: a brief review

“…Some recent Arabic reports showed that the incidence of thrombocytopenia and peculiar thrombotic events might be more common in viral vector technology based COVID-19 vaccine [ 25 , 26 ]. According to the recent management recommendation, mass COVID-19 vaccination should continue but with special caution [ 27 ].

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“…As earlier mentioned, number of cases with COVID-19/COVID-19 vaccine related thrombosis should continue if the COVID-19 pandemic still persists. Although the main exact pathogenic mechanisms are unknown, both vaccine and host factors should play important roles [ 27 ]. More case reports and studies on clinical epidemiology, clinical feature and management of the cases will be the future trend.…”