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Procoagulant Platelet Characterization by Measuring Phosphatidylserine Exposure and Microvesicle Release from Human Purified Platelets
Published on: November 29, 2024
Antiphospholipid syndrome, thrombosis, and vaccination in the COVID-19 pandemic
Tatjana Zekić1,2, Andrej Belančić3,4
1Clinical Hospital Center Rijeka, Department of Rheumatology and Clinical Immunology, University of Rijeka, Faculty of Medicine, Rijeka, Croatia. tatjana.zekic@ri.t-com.hr.
Insights
Antiphospholipid antibodies (aPLs) in COVID-19 are common but not linked to thrombosis. COVID-19 vaccination is safe for antiphospholipid syndrome (APS) patients, easing concerns for those with aPLs.
Area of Science:
- Immunology
- Hematology
- Infectious Diseases
Background:
- Thrombosis is a key feature of both antiphospholipid syndrome (APS) and COVID-19.
- The precise mechanisms linking APS and COVID-19-associated thrombosis are still under investigation.
- The co-occurrence of APS and COVID-19 presents diagnostic and management challenges.
Purpose of the Study:
- To review the interplay between antiphospholipid antibodies (aPLs), APS, COVID-19, and thrombosis.
- To discuss diagnostic insights regarding aPLs in the context of COVID-19.
- To evaluate the safety and tolerability of COVID-19 vaccination in APS patients.
Main Methods:
- Narrative review of existing literature.
- Analysis of studies on aPL prevalence in COVID-19 patients.
- Examination of data on thrombosis and thrombocytopenia in APS and post-vaccination.
Main Results:
- Antiphospholipid antibodies (aPLs) are prevalent in severe COVID-19 but not consistently associated with thrombosis or adverse outcomes.
- Thrombosis and thrombocytopenia are rare but recognized complications of mRNA COVID-19 vaccination.
- COVID-19 vaccination appears safe and well-tolerated in APS patients, including those with triple-positive aPL status.
Conclusions:
- Monitoring aPL positivity over time is crucial for APS diagnosis.
- COVID-19 vaccination may alleviate concerns for APS/aPL-positive individuals regarding immunization.
- Further research is needed to fully elucidate the complex interactions between aPLs, APS, COVID-19, and thrombosis.
Abstract:
Thrombosis is one of the many signs of antiphospholipid syndrome (APS) and COVID-19 infection. Although the mechanisms contributing to thrombosis in APS and COVID-19 are relatively similar, this remains an open subject. Even now (when the COVID-19 pandemic has subsided), there is no conclusive solution to APS and COVID-19 co-occurrence. The presence of newly generated antiphospholipid antibodies (aPLs) in COVID-19 infection may or may not be connected to the diagnosis of APS. The prevalence of aPLs is substantial in severe COVID-19 but not related to thrombosis or a worse outcome. Adequate monitoring of antibody positivity over time is recommended for APL diagnosis. On the other hand, thrombosis and thrombocytopenia can rarely occur with vaccination with mRNA vaccines. Some studies have shown that COVID-19 immunization is well tolerated among APS patients who are triple-positive for aPL, which may comfort patients and referring physicians and lessen hesitation in unvaccinated APS/aPL-positive patients. In this narrative review, we will give an overview of the interaction between aPL-APS-COVID-19-thrombosis and related diagnostic insights learned during the pandemic.
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