Outcomes associated with antiphospholipid antibodies in COVID-19: A prospective cohort study

Serum anti-lipid antibodies in patients affected by leprosy in a high-burden municipality in Brazil: a cross-sectional study

Early diagnosis plays a pivotal role in breaking the epidemiological chain of Mycobacterium leprae transmission. Currently, diagnosis relies on clinical, dermato-neurological features, and histological/microbiological assessments. This prospective cross-sectional study investigated whether IgA, IgM, and IgG anti-lipid antibodies can be used to improve the diagnostic performance for leprosy-affected patients in a high-burden municipality in Brazil. Serum samples from 91 volunteers, including patients with leprosy (n=62), household contacts (n=21), and endemic controls (n=8) were screened by enzyme-linked immunosorbent assays (ELISA) for IgA, IgM, and total IgG against four lipids-namely, cardiolipin (CL), phosphatidylcholine (PTC), phosphatidylethanolamine (PE), and phosphatidylinositol (PI)-and a glycosphingolipid-sulfatide (SL)-found in the bacterial cell wall. Antibodies against all lipids were detected in the sera of patients with leprosy. Significantly higher levels of IgA anti-CL, anti-PE, and anti-PTC, IgM anti-CL, and total IgG anti-PTC were observed in these patients compared to household contacts and endemic controls (p < 0.0001). ROC curve analyses demonstrated high accuracy in discriminating patients with leprosy from the contacts, with moderate to high sensitivity and specificity, even in paucibacillary patients. Despite the small study population and the absence of patients with other dermatological lesions for differential diagnosis, these findings suggest the potential of anti-lipid antibodies as biomarkers for leprosy detection. This approach offers a promising method to improve early diagnosis in high-burden areas, such as the studied municipality in Brazil.

Antiphospholipid Antibodies and COVID-19: A Systematic Review of Clinical Implications

INTRODUCTION

As the COVID-19 pandemic transitions, understanding the intricate dynamics of the disease becomes paramount. This systematic review explores the role of antiphospholipid antibodies in COVID-19, focusing on their potential clinical implications.

METHODS

This systematic review, following PRISMA guidelines, assesses studies exploring the link between antiphospholipid antibodies and COVID-19. PubMed/Medline, Embase, and Scopus were searched for relevant studies published up to December 22, 2024. Inclusion criteria comprised studies involving patients diagnosed with COVID-19 and reporting on the presence of antiphospholipid antibodies. The risk of bias in individual studies was evaluated using the Joanna Briggs Institute appraisal tool.

RESULTS

Our Study includes 59 records involving a total of 28,489 COVID-19 patients. Antiphospholipid antibodies were tested in 14,498 COVID-19 patients. It was observed that 50.84% of patients tested positive for antiphospholipid antibodies. Various types of antiphospholipid antibodies, including Anticardiolipin, Anti beta2 glycoproteins, and Lupus anticoagulant antibody, displayed prevalence rates in the patients with thrombosis. The overall frequency of antiphospholipid antibodies in thrombosis patients was 38.55%.

CONCLUSION

The presence of antiphospholipid antibodies in a significant proportion of COVID-19 patients underscores the need for a detailed investigation into their role in thrombotic events. Our study highlights potential avenues for targeted interventions. However, the evolving nature of COVID-19 necessitates continued research efforts to clarify clinical implications and optimize management strategies in this complex landscape of thrombosis and immunology. The review reveals some limitations, such as variability in study designs and demographics and inherent differences in methodologies among included studies. Future studies should address these limitations with standardized methodologies for more conclusive findings.

Antiphospholipid syndrome, thrombosis, and vaccination in the COVID-19 pandemic

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.

Thrombosis and antiphospholipid antibodies in Japanese COVID-19: based on propensity score matching

Background

Thrombosis is a unique complication of coronavirus disease 2019 (COVID-19). Although antiphospholipid antibodies (aPL) are detected in COVID-19 patients, their clinical significance remains elusive. We evaluated the prevalence of aPL and serum concentrations of beta-2 glycoprotein I (β2GPI), a major self-antigen for aPL, in Japanese COVID-19 patients with and without thrombosis.

Methods

This retrospective single-center nested case-control study included 594 hospitalized patients with COVID-19 between January 2020 and August 2021. Thrombotic complications were collected from medical records. Propensity score-matching method (PSM) (1:2 matching including age, sex, severity on admission, and prior history of thrombosis) was performed to compare the prevalence and titer of aPL (anti-cardiolipin (aCL) IgG/IgM, anti-β2GPI IgG/IgM/IgA, and anti-phosphatidylserine/prothrombin antibody (aPS/PT) IgG/IgM) and serum β2GPI concentration. In addition, PSM (1:1 matching including age and sex) was performed to compare the serum β2GPI concentration between COVID-19 patients and healthy donors.

Results

Among the patients, 31 patients with thrombosis and 62 patients without were compared. The prevalence of any aPLs was indifferent regardless of the thrombosis (41.9% in those with thrombosis vs. 38.7% in those without, p =0.82). The positive rates of individual aPL were as follows: anti-CL IgG (9.7% vs. 1.6%, p =0.11)/IgM (0% vs. 3.2%, p =0.55), anti-β2GP1 IgG (22.6% vs. 9.7%, p =0.12)/IgA (9.7% vs. 9.7%, p =1.0)/IgM (0% vs. 0%, p =1.0), and anti-PS/PT IgG (0% vs. 1.6%, p =1.0)/IgM (12.9% vs. 21.0%, p =0.41), respectively. The aPL titers were also similar regardless of thrombosis. The levels of β2GPI in COVID-19 patients were lower than those in the healthy donors.

Conclusion

Although aPLs were frequently detected in Japanese COVID-19 patients, their prevalence and titer were irrelevant to thrombotic complications. While COVID-19 patients have lower levels of serum β2GPI than healthy blood donors, β2GPI levels were indifferent regardless of thrombosis. Although most of the titers were below cut-offs, positive correlations were observed among aPLs, suggesting that the immune reactions against aPL antigens were induced by COVID-19. We should focus on the long-term thromboembolic risk and the development of APS in the aPL-positive patients with high titer or multiple aPLs.