Antiphospholipid antibodies in patients with COVID-19: A relevant observation?

Prevalence of antiphospholipid antibodies in COVID-19 patients: A meta-analysis

OBJECTIVE

In some reports, antiphospholipid antibodies (aPL) prevalence is higher in COVID-19 patients. This study intended to compare aPL prevalence between COVID-19 patients and healthy controls, and differences in aPL types using meta-analysis.

METHODS

This work retrieved published literature about association between COVID-19 and aPL from Embase, Web of Science, PubMed, and The Cochrane Library databases. The observation group was COVID-19 patients, and the control group was healthy individuals. Outcome measures contained any of following aPLs: classic aPL: anti-cardiolipin antibodies (aCL) and anti-β2-glycoprotein-1 antibodies (Anti-β2GP1); other non-criteria aPL: anti-phosphatidylserine/prothrombin antibodies (aPS/PT) and anti-annexin-V antibodies (AnV). Meta-analysis was done on Review Manager 5.4.

RESULTS

10 studies involving 2288 patients were deemed eligible for inclusion. The results of the meta-analysis showed that the prevalence of Classic aPL and Any aPL in the COVID-19 group was significantly higher than in the healthy group (Classic aPL, RR = 2.55, 95 % CI = 1.83-3.55, P < 0.00001; Any aPL, RR = 2.34, 95 % CI = 1.46-3.77, P = 0.0005). Anti-β2GP1 IgA antibodies were the most common aPL in COVID-19 patients, with a significantly higher prevalence than in the healthy group (RR = 4.26, 95 % CI = 2.84-6.40, P < 0.00001). The prevalence of the four types of IgM aPL was significantly higher in the COVID-19 group compared to the healthy group, while there was no significant difference in aPL IgG between the two groups.

CONCLUSION

The prevalence of aPL in COVID-19 patients was significantly higher than in the healthy control group. IgM aPL was more easily detectable in the early stages of COVID-19 infection, while IgG aPL may be of more concern in the later time points of the immune epidemiology following SARS-CoV-2 infection.

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.

Autoantibodies in COVID-19: implications for disease severity and clinical outcomes

Few pathogens have historically been subjected to as intense scientific and clinical scrutiny as SARS-CoV-2. The genetic, immunological, and environmental factors influencing disease severity and post-infection clinical outcomes, known as correlates of immunity, remain largely undefined. Clinical outcomes of SARS-CoV-2 infection vary widely, ranging from asymptomatic cases to those with life-threatening COVID-19 symptoms. While most infected individuals return to their former health and fitness within a few weeks, some develop debilitating chronic symptoms, referred to as long-COVID. Autoimmune responses have been proposed as one of the factors influencing long-COVID and the severity of SARS-CoV-2 infection. The association between viral infections and autoimmune pathologies is not new. Viruses such as Epstein-Barr virus and cytomegalovirus, among others, have been shown to induce the production of autoantibodies and the onset of autoimmune conditions. Given the extensive literature on SARS-CoV-2, here we review current evidence on SARS-CoV-2-induced autoimmune pathologies, with a focus on autoantibodies. We closely examine mechanisms driving autoantibody production, particularly their connection with disease severity and long-COVID.

Bioinformatics and systems-biology approach to identify common pathogenic mechanisms for COVID-19 and systemic lupus erythematosus

BACKGROUND

The Coronavirus disease 2019 (COVID-19) pandemic has brought a heavy burden to the world, interestingly, it shares many clinical symptoms with systemic lupus erythematosus (SLE). It is unclear whether there is a similar pathological process between COVID-9 and SLE. In addition, we don't know how to treat SLE patients with COVID-19. In this study, we analyse the potential similar pathogenesis between SLE and COVID-19 and explore their possible drug regimens using bioinformatics and systems biology approaches.

METHODS

The common differentially expressed genes (DEGs) were extracted from the COVID-19 datasets and the SLE datasets for functional enrichment, pathway analysis and candidate drug analysis.

RESULT

Based on the two transcriptome datasets between COVID-19 and SLE, 325 common DEGs were selected. Hub genes were identified by protein-protein interaction (PPI) analysis. few found a variety of similar functional changes between COVID-19 and SLE, which may be related to the pathogenesis of COVID-19. Besides, we explored the related regulatory networks. Then, through drug target matching, we found many candidate drugs for patients with COVID-19 only or COVID-19 combined with SLE.

CONCLUSION

COVID-19 and SLE patients share many common hub genes, related pathways and regulatory networks. Based on these common targets, we found many potential drugs that could be used in treating patient with COVID-19 or COVID-19 combined with SLE.

Autoantibodies to protein S may explain rare cases of coagulopathy following COVID-19 vaccination

While Coronavirus disease 2019 (COVID-19) vaccines have proven to be both effective and generally safe, rare but severe adverse events following immunization (AEFIs) are described. Autoantibodies to platelet factor-4 are associated with catastrophic thrombotic AEFIs, but comprehensive investigations of other autoantibodies are lacking. We aimed to detect and describe autoantibodies targeting coagulation-related proteins in a population-wide cohort (SWEDEGENE) including AEFIs attributed to COVID-19 vaccines in Sweden. Subjects were recruited from December 2020 to October 2022 and were stratified based on diagnosis and COVID-19 exposure. Screening was carried out in two phases, with a multiplex bead-based assay in the first subset (until September 2021) and with targeted assays for the second (until October 2022). Positivity was defined based on absolute, relative, and biological/technical thresholds. Patients with coagulation-related AEFIs were older and the Vaxzevria vaccine was overrepresented in this group. Two cases had antiphospholipid antibodies but none had PF4 antibodies. We identified six positives for protein S autoantibodies. Protein S concentrations were negatively correlated with autoantibody response in patients with immunoreactivity and functional analysis revealed low protein S activity in three subjects. Our population-wide analysis reveals cases with autoantibodies against protein S which possibly underlie coagulopathic AEFIs.

Thrombosis in Antiphospholipid Syndrome: Current Perspectives and Challenges in Laboratory Testing for Antiphospholipid Antibodies

Antiphospholipid syndrome (APS) diagnosis hinges on identifying antiphospholipid antibodies (aPL). Currently, laboratory testing encompasses lupus anticoagulant (LA), anticardiolipin (aCL), and anti-β2-glycoprotein I antibodies (aβ2GPI) IgG or IgM, which are included in the APS classification criteria. All the assays needed to detect aPL antibodies have methodological concerns. LA testing remains challenging due to its complexity and susceptibility to interference from anticoagulant therapy. Solid phase assays for aCL and aβ2GPI exhibit discrepancies between different assays. Antibody profiles aid in identifying the patients at risk for thrombosis through integrated interpretation of all positive aPL tests. Antibodies targeting domain I of β2-glycoprotein and antiphosphatidylserine-prothrombin antibodies have been evaluated for their role in thrombotic APS but are not yet included in the APS criteria. Detecting these antibodies may help patients with incomplete antibody profiles and stratify the risk of APS patients. The added diagnostic value of other methodologies and measurements of other APS-associated antibodies are inconsistent. This manuscript describes laboratory parameters useful in the diagnosis of thrombotic APS and will concentrate on the laboratory aspects, clinical significance of assays, and interpretation of aPL results in the diagnosis of thrombotic APS.

Effect of vitamin D3 on antiphospholipid antibodies in hospitalized patients with moderate to severe COVID-19

OBJECTIVE

To investigate the effect of a single oral dose of 200,000 IU of vitamin D3 on antiphospholipid antibodies in hospitalized patients with moderate to severe COVID-19.

METHODS

This is a post-hoc, exploratory analysis from a double-blind, placebo-controlled, randomized clinical trial performed in two centers in Sao Paulo, Brazil. Hospitalized patients with COVID-19 were randomly assigned to receive either vitamin D3 (n = 97) or placebo (n = 97). In this post-hoc analysis, the endpoints were titers and frequency of anti-β2-Glycoprotein-I (aβ2-GP) and Anticardiolipin (aCL) antibodies [Immunoglobulin G, M and A (IgG, IgM and IgA)].

RESULTS

Overall mean (SD) age was 55.3 (13.9) years, Body Mass Index (BMI) was 32.2 (7.1 kg/m2), and 106 participants (54.6 %) were male. There was a significant group by time interaction (p = 0.046) for frequency of aCL IgG, with increased values from baseline to discharge in the placebo group [n (%), from 13 (13.4) to 25 (25.8)] compared to the vitamin D3 [from 25 (25.8) to 29 (29.9)]. However, the frequency of aCL IgG did not change between the groups on discharge. No significant differences between vitamin D3 and placebo groups were found for any other autoantibodies.

CONCLUSION

These findings do not support the use of a single oral dose of 200,000 IU of vitamin D3 to modulate autoantibodies in hospitalized patients with moderate to severe COVID-19.

Is lupus anticoagulant testing with dilute Russell's viper venom clotting times reliable in the presence of inflammation?

Background

Testing for lupus anticoagulant (LA) is not recommended in case of inflammation as C-reactive protein (CRP) can interfere in vitro with the phospholipids present in the activated partial thromboplastin time test used to detect an LA. However, the potential interference of an acute phase protein (ie, CRP) in LA testing using the dilute Russell's viper venom (DRVV) test is poorly studied.

Objectives

To study the effect of inflammation, as evidenced by increased CRP levels, on DRVV tests.

Methods

First, a retrospective analysis (2013-2023) was performed: data on all LA workups were retrieved, and the association between CRP levels and DRVV screen, mix, and confirm clotting times was studied. Second, data on DRVV panels and CRP levels were extracted from 2 prospective studies involving intensive care unit patients to study the association between both variables. Third, CRP was added to normal pooled plasma at 6 relevant concentrations (up to 416 mg/L) to study the association between CRP itself and DRVV coagulation times.

Results

In the retrospective analysis, DRVV screen and confirm clotting times significantly increased as CRP increased (increase of 0.11 seconds and 0.03 seconds per 1 mg/L increase of CRP level, respectively). In the prospective analysis, only DRVV screen was prolonged with high CRP levels (increase of 0.06 seconds for a 1 mg/L increase in CRP level); DRVV screen/confirm ratio was also increased with high CRP levels. In vitro, the addition of CRP did not significantly increase any DRVV clotting times.

Conclusion

LA testing should be performed with much caution in the presence of inflammation as it may be associated with prolongation of both activated partial thromboplastin time and DRVV clotting times.

IgA Anti-β2-Glycoprotein I Antibodies as Markers of Thrombosis and Severity in COVID-19 Patients

Patients with COVID-19 may develop a hypercoagulable state due to tissue and endothelial injury, produced by an unbalanced immune response. Therefore, an increased number of thromboembolic events has been reported in these patients. The aim of this study is to investigate the presence of antiphospholipid antibodies (aPL) in COVID-19 patients, their role in the development of thrombosis and their relationship with the severity of the disease. In this retrospective study, serum samples from 159 COVID-19 patients and 80 healthy donors were analysed for the presence of aPL. A total of 29 patients (18.2%) and 14 healthy donors (17.5%) were positive for aPL. Nineteen COVID-19 patients (12%) but no healthy donor presented a positive percentage of the IgA isotype aPL. IgA anti-β2-glycoprotein I antibodies (anti-β2GPI) were the most frequent type (6.3%) in patients but was not detected in any healthy donor. The positivity of this antibody was found to be significantly elevated in patients with thromboembolic events (25% vs. 5%, p = 0.029); in fact, patients with positive IgA anti-β2GPI had an incidence of thrombosis over six times higher than those who had normal antibody concentrations [OR (CI 95%) of 6.67 (1.5-30.2), p = 0.014]. Additionally, patients with moderate-severe disease presented a higher aPL positivity than patients with mild disease according to the Brescia (p = 0.029) and CURB-65 (p = 0.011) severity scales. A multivariate analysis showed that positivity for IgA anti-β2GPI is significantly associated with disease severity measured by CURB-65 [OR (CI 95%) 17.8 (1.7-187), p = 0.0016]. In conclusion, COVID-19 patients have a significantly higher positive percentage of the IgA isotype aPL than healthy donors. IgA anti-β2GPI antibodies were the most frequently detected aPL in COVID-19 patients and were associated with thrombosis and severe COVID-19 and are thus proposed as a possible marker to identify high-risk patients.

Thrombotic Markers in Pregnant Patients with and without SARS-CoV-2 Infection

BACKGROUND

Coronavirus disease 2019 (COVID-19) is associated with coagulation abnormalities and increased risk for venous and arterial thrombi. This study aimed to evaluate D-dimer levels and lupus anticoagulant (LAC) positivity in pregnant individuals with and without Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

STUDY DESIGN

This was a prospective cohort study of pregnant individuals delivering at a single academic institution from April 2020 to March 2022. Individuals with a positive SARS-CoV-2 result during pregnancy were compared with a convenience sample of those without a positive SARS-CoV-2 result. For individuals with SARS-CoV-2 infection, severity was assessed based on the National Institutes of Health classification system. The primary outcome was D-dimer level measured during delivery admission. The secondary outcomes were LAC positivity and thromboembolic events. Outcomes were compared between individuals with and without a positive SARS-CoV-2 result, and further by disease severity.

RESULTS

Of 98 participants, 77 (78.6%) were SARS-CoV-2 positive during pregnancy. Among individuals with SARS-CoV-2 infection, severity was asymptomatic in 20 (26.0%), mild in 13 (16.9%), moderate in 4 (5.2%), severe in 38 (49.4%), and critical in 2 (2.6%). The D-dimer concentration at delivery did not significantly differ between those with a SARS-CoV-2 positive result compared with those without (mean 2.03 µg/mL [95% confidence interval {CI} 1.72-2.40] vs. 2.37 µg/mL [95% CI 1.65-3.40]; p = 0.43). Three individuals (4%) with SARS-CoV-2 infection and none (0%) without infection were LAC positive (p = 0.59). There were no clinically apparent thromboses in either group. D-dimer concentrations and LAC positive results did not differ by COVID-19 severity.

CONCLUSION

Thrombotic markers did not differ in pregnant individuals by SARS-CoV-2 infection; however, high rates of LAC positivity were detected.

KEY POINTS

· Thrombotic markers did not differ in pregnant individuals by SARS-CoV-2 infection.. · Higher than expected rates of LAC positivity were detected.. · There were no clinically apparent thromboses..

Antiphospholipid antibody-related hepatic vasculitis in a juvenile after non-severe COVID-19: a case report and literature review

Antiphospholipid antibodies (aPL) are both laboratory evidence and causative factors for a broad spectrum of clinical manifestations of antiphospholipid syndrome (APS), with thrombotic and obstetric events being the most prevalent. Despite the aPL-triggered vasculopathy nature of APS, vasculitic-like manifestations rarely exist in APS and mainly appear associated with other concurrent connective tissue diseases like systemic lupus erythematous. Several studies have characterized pulmonary capillaritis related to pathogenic aPL, suggesting vasculitis as a potential associated non-thrombotic manifestation. Here, we describe a 15-year-old girl who develops hepatic infarction in the presence of highly positive aPL, temporally related to prior non-severe COVID-19 infection. aPL-related hepatic vasculitis, which has not been reported before, contributes to liver ischemic necrosis. Immunosuppression therapy brings about favorable outcomes. Our case together with retrieved literature provides supportive evidence for aPL-related vasculitis, extending the spectrum of vascular changes raised by pathogenic aPL. Differentiation between thrombotic and vasculitic forms of vascular lesions is essential for appropriate therapeutic decision to include additional immunosuppression therapy. We also perform a systematic review to characterize the prevalence and clinical features of new-onset APS and APS relapses after COVID-19 for the first time, indicating the pathogenicity of aPL in a subset of COVID-19 patients.

Do we need more guidance on thrombophilia testing? Challenges and special considerations

INTRODUCTION

Thrombophilia testing (TT) is a laboratory procedure designed to detect the risk factors involved in the pathogenesis of vascular occlusions. The role of TT is also controversial because it has a limited impact on the choice and duration of antithrombotic treatments.

AREAS COVERED

We reviewed, by examining MEDLINE up to October 2023. Accepted and not accepted thrombophilia markers are discussed along with the appropriateness or not of prescribing TT in several conditions such as: provoked and unprovoked venous thromboembolism (VTE), women who are planning a pregnancy whose relatives had VTE or have a hereditary thrombophilia, before assumption of estro-progestins, after multiple pregnant loss, arterial thrombosis, retinal vein occlusion, and splanchnic vein thrombosis.

EXPERT OPINION

TT is not essential in the management of VTE, but it may be useful for limiting adverse events in case of thrombophilia. We expose our criticism of items afforded by other guidelines by presenting our opinion based on both the scientific evidence and clinical practice. We also deal with common mistakes in prescribing and interpretations of TT hoping to purpose an educational approach on this topic. Finally, we emphasize the creation of the expert in hemostasis and thrombosis who should be present in every hospital.

It's in the blood: a review of the hematological system in SARS-CoV-2-associated COVID-19

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to an unprecedented global healthcare crisis. While SARS-CoV-2-associated COVID-19 affects primarily the respiratory system, patients with COVID-19 frequently develop extrapulmonary manifestations. Notably, changes in the hematological system, including lymphocytopenia, neutrophilia and significant abnormalities of hemostatic markers, were observed early in the pandemic. Hematological manifestations have since been recognized as important parameters in the pathophysiology of SARS-CoV-2 and in the management of patients with COVID-19. In this narrative review, we summarize the state-of-the-art regarding the hematological and hemostatic abnormalities observed in patients with SARS-CoV-2-associated COVID-19, as well as the current understanding of the hematological system in the pathophysiology of acute and chronic SARS-CoV-2-associated COVID-19.

Anti-phospholipid autoantibodies in human diseases

Anti-phospholipid autoantibodies are a group of antibodies that can specifically bind to anionic phospholipids and phospholipid protein complexes. Recent studies have reported elevated serum anti-phospholipid autoantibody levels in patients with antiphospholipid syndrome, systemic lupus erythematosus, rheumatoid arthritis, metabolic disorders, malaria, SARS-CoV-2 infection, obstetric diseases and cardiovascular diseases. However, the underlying mechanisms of anti-phospholipid autoantibodies in disease pathogenesis remain largely unclear. Emerging evidence indicate that anti-phospholipid autoantibodies modulate NETs formation, monocyte activation, blockade of apoptotic cell phagocytosis in macrophages, complement activation, dendritic cell activation and vascular endothelial cell activation. Herein, we provide an update on recent advances in elucidating the effector mechanisms of anti-phospholipid autoantibodies in the pathogenesis of various diseases, which may facilitate the development of potential therapeutic targets for the treatment of anti-phospholipid autoantibody-related disorders.

Lupus Anticoagulant Detection under the Magnifying Glass

Diagnosis of antiphospholipid syndrome (APS) requires the presence of a clinical criterion (thrombosis and/or pregnancy morbidity), combined with persistently circulating antiphospholipid antibodies (aPL). Lupus anticoagulant (LA) is one of the three laboratory parameters (the others being antibodies to either cardiolipin or β2-glycoprotein I) that defines this rare but potentially devastating condition. For the search for aCL and aβ2-GP-I, traditionally measured with immunological solid-phase assays (ELISA), several different assays and detection techniques are currently available, thus making these tests relatively reliable and widespread. On the other hand, LA detection is based on functional coagulation procedures that are characterized by poor standardization, difficulties in interpreting the results, and interference by several drugs commonly used in the clinical settings in which LA search is appropriate. This article aims to review the current state of the art and the challenges that clinicians and laboratories incur in the detection of LA.

Prevalence, clinical significance, and persistence of autoantibodies in COVID-19

BACKGROUND

Interest in complications and sequelae following Coronavirus disease 2019 (COVID-19) is increasing. Several articles have reported COVID-19-associated autoimmune diseases and the association between autoantibodies and the severity of COVID-19. Thromboembolic complications are frequent in patients with COVID-19, and the anti-phospholipid antibodies (aPL) is frequently detected. We conducted this study to investigate the prevalence, clinical significance, and persistence of anti-nuclear antibodies (ANA) and aPLs in COVID-19.

METHODS

We enrolled patients diagnosed with COVID-19 with oxygen demand and admitted to a tertiary hospital in South Korea between July 2020 and March 2022. ANA and aPLs levels were assessed using an immunoassay kit.

RESULTS

A total of 248 patients were enrolled in the study. Among them, five patients were ANA-positive, and 41 were aPL-positive (IgM anti-cardiolipin (aCL) antibody in seven patients, IgG aCL in seven patients, IgM anti-β2Glycoprotein1 antibody (aβ2-GPI) in 32 patients, and IgG aβ2-GPI in one patient). Two of five ANA-positive patients, 13 of 32 IgM aβ2-GPI-positive patients, 5 of 7 IgM aCL-positive patients, and 2 of 7 IgG aCL-positive patients were eligible for follow-up analysis, and 100%, 69.2%, 40%, and 50% of the patients remained autoantibody-positive, respectively. There were no differences in clinical outcomes between the autoantibody-positive and autoantibody-negative groups, except for the IgG aCL group showing a tendency for worse outcomes.

CONCLUSION

A significant proportion of COVID-19 patients with oxygen demand were autoantibody-positive, and autoantibodies persisted for several months after symptom onset. Whether these autoantibodies are related to long-term sequelae in COVID-19 patients requires further investigation.

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.

SARS-CoV-2 infection and SLE: endothelial dysfunction, atherosclerosis, and thrombosis

An increased risk of atherosclerotic and thrombotic complications characterizes connective tissue diseases. Endothelial dysfunction is the basis for the initiation and progression of atherosclerosis and thrombosis. We present systemic lupus erythematosus (SLE) as a model rheumatic disease with endothelial dysfunction and discuss its mechanisms, factors that influence the early onset and rapid progression of atherosclerosis, and the increased risk of thromboembolic events. We focus on established methods to improve endothelium function, including statins, antiplatelet, and antithrombotic therapy. Hypercoagulable and hypofibrinolitic states and a hyperinflammatory response characterize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Several pathogenic mechanisms are typical for an acute phase of Covid-19 post-Covid syndrome and connective tissue diseases: endothelial dysfunction, elevated antiphospholipid antibody titer, activation of the complement system, and formation of extracellular neutrophil traps (NET). The current review discusses the mechanisms underlying SLE and the COVID-19 in the context of endothelial function, atherosclerosis, and thrombosis (Graphical abstract). Key Points • The pathophysiology of systemic lupus erythematosus (SLE) and Covid-19 shows some similarities, such as endothelial cell activation and dysfunction, the activation of complementary systems, the presence of antiphospholipid antibodies, and the formation of extracellular neutrophil traps. • Autoimmunity in both diseases creates the basis for hyperinflammatory, hypercoagulable, and hypofibrinolitic states and their thromboembolic complications. • This paper presents our perspective on the mechanisms behind the cardiovascular manifestations of SLE and COVID-19, with a particular emphasis on endothelial dysfunction. Covid-19 and systemic lupus erythematosus-potential similarities in pathophysiology. Figures of the panel illustrate the clinical manifestations of endothelial dysfunction, atherosclerosis, and thromboembolism, including coronary artery disease ([A] coronary angiography with left anterior descending artery stenosis and [B] scintigraphy with reduced perfusion in the myocardial apical segments), stroke ([C] carotid angiography, left carotid artery occlusion) and pulmonary embolism ([D]computed tomography with thrombus in the right pulmonary artery).

Effect of COVID-19 inactivated vaccine on peripheral blood anti-β2-GPI antibody and outcomes in vitro fertilization-embryo transplantation

Corona Virus Disease 2019 (COVID-19) is an acute respiratory infection and a global public health event. The level of aβ2GPI is significantly up-regulated in COVID-19 patients. The impact of inactivated vaccination against COVID-19 on aβ2GPI and in vitro fertilization and embryo transfer (IVF-ET) remains unknown amidst the universal administration of COVID-19 vaccines. We conducted a retrospective study to assess the impact of COVID-19 inactivated vaccination on aβ2GPI levels and its effect on superovulation and pregnancy outcomes. We found aβ2GPI level is significantly up-regulated after vaccination. There was no statistical difference in mature egg rate, 2PN fertilization rate, day 3 high-quality embryo rate, blastocyst formation rate, embryo implantation rate and miscarriage rate between the vaccine group and control group. Our findings showed vaccination with COVID-19 inactivated vaccine can elevate the level of aβ2GPI in peripheral blood but have no effect on the outcomes of controlled ovarian hyperstimulation and pregnancy in IVF-ET.

Thrombosis and Hyperinflammation in COVID-19 Acute Phase Are Related to Anti-Phosphatidylserine and Anti-Phosphatidylinositol Antibody Positivity

Antiphospholipid antibodies (APLA) are strongly associated with thrombosis seen in patients with antiphospholipid syndrome. In COVID-19, thrombosis has been observed as one of the main comorbidities. In patients hospitalised for COVID-19, we want to check whether APLA positivity is associated with COVID-19-related thrombosis, inflammation, severity of disease, or long COVID-19. We enrolled 92 hospitalised patients with COVID-19 between March and April 2020 who were tested for 18 different APLAs (IgG and IgM) with a single line-immunoassay test. A total of 30 healthy blood donors were used to set the cut-off for each APLA positivity. Of the 92 COVID-19 inpatients, 30 (32.61%; 95% CI [23.41-43.29]) tested positive for APLA, of whom 10 (33.3%; 95% CI [17.94-52.86]) had more than one APLA positivity. Anti-phosphatidylserine IgM positivity was described in 5.4% of inpatients (n = 5) and was associated with the occurrence of COVID-19-related thrombosis (p = 0.046). Anti-cardiolipin IgM positivity was the most prevalent among the inpatients (n = 12, 13.0%) and was associated with a recorded thrombosis in their clinical history (p = 0.044); however, its positivity was not associated with the occurrence of thrombosis during their hospitalisation for COVID-19. Anti-phosphatidylinositol IgM positivity, with a prevalence of 5.4% (n = 5), was associated with higher levels of interleukin (IL)-6 (p = 0.007) and ferritin (p = 0.034). Neither of these APLA positivities was a risk factor for COVID-19 severity or a predictive marker for long COVID-19. In conclusion, almost a third of COVID-19 inpatients tested positive for at least one APLA. Anti-phosphatidylserine positivity in IgM class was associated with thrombosis, and anti-phosphatidylinositol positivity in IgM class was associated with inflammation, as noticed by elevated levels of IL-6. Thus, testing for non-criteria APLA to assess the risk of clinical complications in hospitalised COVID-19 patients might be beneficial. However, they were not related to disease severity or long COVID-19.

Lupus anticoagulants as a prospective independent predictor in COVID-19 patients

OBJECTIVE

Lupus anticoagulant (LA) are commonly detected during SARS-CoV-2 infection. However, the relationship between LA and clinical significance is still unclear.

METHODS

A retrospective chart analysis was performed on COVID-19 patients who were tested for LA at our hospital from March 2020 to November 2021. We analyzed the patient's characteristics based on the result of the LA test. In addition, subgroup analysis performed the LA-positive group who had undergone serial LA tests.

RESULTS

A total of 219 COVID-19 patients were enrolled in the study, 148 patients (67.6%) were positive for LA test. The LA-positive group received more treatment of high flow nasal cannula (LA-positive 73.0%, LA-negative 57.7%, p = 0.024). The LA-positive group showed prolonged aPTT, higher levels of CRP and fibrinogen (all p's < 0.05). Among 148 LA-positive patients, 127 patients (86.5%) were found to be LA-positive within 10 days of SARS-CoV-2 positive, and LA-positive group confirmed a median time to LA loss of 10 days. However, there was a group that was negative for LA in the early stages of infection and became positive about 13 days later. A subgroup analysis showed that these patients had different characteristics due to their longer hospital stays and higher D-dimer levels.

CONCLUSIONS

In COVID-19 patients, LA is expected to be associated to disease severity. Since the clinical significance of LA is different depending on the onset time of LA positivity, the LA test is suggested to be done at diagnosis of SARS-CoV-2 infection, even if LA is negative, follow-up test should be considered within 10 days.

The APSANTICO Study: A Prospective Observational Study to Evaluate Antiphospholipid Antibody Profiles in Patients with Thromboembolic Antiphospholipid Syndrome (APS) after COVID-19 Infection and/or Vaccination

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a new virus discovered in December 2019 that causes coronavirus disease 19 (COVID-19) and various vaccinations have been developed. The extent to which COVID-19 infections and/or COVID-19 vaccinations alter antiphospholipid antibodies (aPL) in patients with thromboembolic antiphospholipid syndrome (APS) remains unclear. Eighty-two patients with confirmed thromboembolic APS were included in this prospective non-interventional trial. Blood parameters including lupus anticoagulants, anticardiolipin IgG- and IgM-antibodies, and anti-ß2-glycoprotein I IgG- and IgM-antibodies were assessed prior to and after COVID-19 vaccination and/or COVID-19 infection. No increases in aPL in the total study population were detected. In fact, low but significant decreases were observed for anticardiolipin IgG- and anti-β2-glycoprotein I IgG-antibodies, while anticardiolipin IgM- and anti-b2-glycoprotein I IgM-antibodies slightly increased only in patients with COVID-19 infection and vaccination. Although the investigated patient group is known to have a high risk of recurrent thrombosis, only one arterial thrombotic event was diagnosed (1.2%, 1/82). This low recurrence rate was probably due to the high vaccination rates prior to infections and a high rate of effective anticoagulation. Our data show that COVID-19 infections and/or vaccinations do not deteriorate the clinical course of anticoagulated thromboembolic APS patients.

Risk factors for persistent positive anticardiolipin antibodies in women with recurrent pregnancy loss

Antiphospholipid syndrome (APS) is an established cause of recurrent pregnancy loss (RPL). It is necessary to detect persistently positive antiphospholipid antibodies to diagnose APS. This study aimed to explore risk factors for persistent anticardiolipin (aCL) positivity. Women with a history of RPL or with a history of one or more intrauterine fetal deaths after 10 weeks underwent examinations to determine the causes of RPL, including antiphospholipid antibodies. If aCL-IgG or aCL-IgM antibodies were positive, retests were performed at least 12 weeks apart. Risk factors for persistent aCL antibody positivity were retrospectively investigated. The number and percentage of cases above the 99th percentile were 74/2399 (3.1%) for aCL-IgG, and 81/2399 (3.5%) for aCL-IgM. Of the initially tested cases, 2.3% (56/2399) for aCL-IgG and 2.0% (46/2289) for aCL-IgM were ultimately positive above the 99th percentile in retests. Retest values after 12 weeks were significantly lower than the initial values for both IgG and IgM immunoglobulin classes. Initial aCL antibody titers were significantly higher in the persistent-positive group than in the transient-positive group for both IgG and IgM immunoglobulin classes. The cut-off values for predicting persistent positivity of aCL-IgG antibodies and aCL-IgM antibodies were 15 U/mL (99.1 percentile) and 11 U/mL (99.2 percentile), respectively. The only risk factor for persistently positive aCL antibodies is a high antibody titer during the initial test. When the aCL antibody titer in the initial test exceeds the cut-off value, therapeutic strategies can be defined in subsequent pregnancies without waiting for 12 weeks.

Antiphospholipid syndrome: advances in diagnosis, pathogenesis, and management

Antiphospholipid syndrome (APS) is a thrombo-inflammatory disease propelled by circulating autoantibodies that recognize cell surface phospholipids and phospholipid binding proteins. The result is an increased risk of thrombotic events, pregnancy morbidity, and various other autoimmune and inflammatory complications. Although antiphospholipid syndrome was first recognized in patients with lupus, the stand alone presentation of antiphospholipid syndrome is at least equally common. Overall, the diagnosis appears to affect at least one in 2000 people. Studies of antiphospholipid syndrome pathogenesis have long focused on logical candidates such as coagulation factors, endothelial cells, and platelets. Recent work has shed light on additional potential therapeutic targets within the innate immune system, including the complement system and neutrophil extracellular traps. Vitamin K antagonists remain the mainstay of treatment for most patients with thrombotic antiphospholipid syndrome and, based on current data, appear superior to the more targeted direct oral anticoagulants. The potential role of immunomodulatory treatments in antiphospholipid syndrome management is receiving increased attention. As for many systemic autoimmune diseases, the most important future direction is to more precisely identify mechanistic drivers of disease heterogeneity in pursuit of unlocking personalized and proactive treatments for patients.

From Co-Infections to Autoimmune Disease via Hyperactivated Innate Immunity: COVID-19 Autoimmune Coagulopathies, Autoimmune Myocarditis and Multisystem Inflammatory Syndrome in Children

Neutrophilia and the production of neutrophil extracellular traps (NETs) are two of many measures of increased inflammation in severe COVID-19 that also accompany its autoimmune complications, including coagulopathies, myocarditis and multisystem inflammatory syndrome in children (MIS-C). This paper integrates currently disparate measures of innate hyperactivation in severe COVID-19 and its autoimmune complications, and relates these to SARS-CoV-2 activation of innate immunity. Aggregated data include activation of Toll-like receptors (TLRs), nucleotide-binding oligomerization domain (NOD) receptors, NOD leucine-rich repeat and pyrin-domain-containing receptors (NLRPs), retinoic acid-inducible gene I (RIG-I) and melanoma-differentiation-associated gene 5 (MDA-5). SARS-CoV-2 mainly activates the virus-associated innate receptors TLR3, TLR7, TLR8, NLRP3, RIG-1 and MDA-5. Severe COVID-19, however, is characterized by additional activation of TLR1, TLR2, TLR4, TLR5, TLR6, NOD1 and NOD2, which are primarily responsive to bacterial antigens. The innate activation patterns in autoimmune coagulopathies, myocarditis and Kawasaki disease, or MIS-C, mimic those of severe COVID-19 rather than SARS-CoV-2 alone suggesting that autoimmunity follows combined SARS-CoV-2-bacterial infections. Viral and bacterial receptors are known to synergize to produce the increased inflammation required to support autoimmune disease pathology. Additional studies demonstrate that anti-bacterial antibodies are also required to account for known autoantigen targets in COVID-19 autoimmune complications.

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

Background

The significance of antiphospholipid antibodies (aPL) in COVID-19 remains uncertain.

Objectives

We determined whether aPL are associated with COVID-19 and/or thrombosis or adverse outcomes during hospitalization for COVID-19.

Methods

Symptomatic adults tested for SARS-CoV-2 for clinical reasons (March-July 2020) with either ≥1 positive polymerase chain reaction (COVID-19+) or all negative (non-COVID-19) results were recruited to a biobank collecting plasma, clinical data, and outcomes. We tested baseline plasma samples (days 0-7) of all subjects (and day-30 samples in the COVID-19+ subjects, when available) for aPL (anticardiolipin immunoglobulin [Ig]M/IgG, anti-β2-glycoprotein I IgM/IgG, antiphosphatidylserine/prothrombin IgM/IgG, and lupus anticoagulant). We compared the baseline prevalence of aPL between the COVID-19+ and non-COVID-19 subjects. Among hospitalized COVID-19+ subjects, multivariable logistic regression was used to evaluate the association of aPL (and their subtypes) with arterial or venous thromboembolic events, acute kidney injury, intensive care unit admission, mechanical ventilation, and death after adjusting for potential confounders.

Results

At baseline, 123 of 289 (43%) COVID+ subjects had ≥1 aPL versus 116 of 261 (32%) non-COVID-19 subjects (difference, 10%; 95% CI, 3%-18%). Among 89 COVID+ subjects with repeated samples, aPL persisted on day 30 in 15 of 34 (44%) subjects with baseline aPL positivity, and half of those without aPL at baseline developed one or more new aPL. In hospitalized COVID-19 subjects (n = 241), baseline aPL positivity was associated with acute kidney injury (odds ratio [OR], 1.8; 95% CI, 1.1-3.2) and mechanical ventilation (OR, 3.2; 95% CI, 1.5-6.8) but not death (OR, 1.2; 95% CI, 0.6-2.5). In secondary analyses, medium-to-high titers of anticardiolipin IgG (>40) were associated with thromboembolic events (OR, 7.3; 95% CI, 1.8-30.1).

Conclusion

In patients with COVID-19, aPL may help identify an increased risk of thrombosis and other adverse outcomes.

Lupus Anticoagulant Is Associated with Critical Cases and High Mortality in COVID-19: A Literature Review

Background

In severe COVID-19 cases, a hypercoagulable state may occur. Antiphospholipid syndrome-related auto-antibodies (APSRAs) contribute to coagulopathy, but their role in COVID- 19 remains unclear. We aimed to investigate the prevalence of positive APSRAs and their effect on clinical outcomes in confirmed COVID-19 patients.

Materials and Methods

In this cross-sectional study, severe hospitalized COVID-19 cases were enrolled. Demographic and clinical data were obtained from the day of admission. APSRAs including IgG and/or IgM anticardiolipin (aCL) and anti-β2-glycoprotein1 (anti-β2GP1) as well as lupus anticoagulant (LAC) were measured.

Results

In this study, 54 severe COVID-19 cases with positive RT-PCR and chest CT scans were recruited. Positive APSRAs were found in 7 (12.9%) patients. Positive LAC was a more prevalent marker as compared to other tests (11.1%). The prevalence of positive aCL (IgM or IgG) and anti-ß2 GPI (IgM or IgG) was 1.8% (in an elderly woman). Lower oxygen saturation was found in the positive APSRAs group as opposed to the negative APSRAs group (70.3±9 vs. 84.8±9.7%). The mortality rate in the positive APSRAs group was significantly higher relative to the negative APSRAs group (83.3% vs. 27.1%; P-value: 0.01). Likewise, the mechanical ventilation requirement in the positive group was also higher (50% vs. 27.1%, P-value: 0.28).

Conclusion

This study indicated that LAC might be associated with critical cases and high mortality of COVID-19. Nonetheless, the mortality was not related to macrothrombotic incidence.

Evaluating the Relationship Between Antiphospholipid Antibodies and COVID-19 Severity

Coronavirus 2 (COVID-19) has emerged as a new global pandemic, causing severe acute respiratory syndrome. Furthermore, the existence of antiphospholipid (APL) antibodies (Abs) and ultimately patient death may be linked to the occurrence of thrombotic events in patients with COVID-19. We aimed to investigate if there was a link between the presence of APL Abs and the severity of COVID-19 disease in patients at the Vali-Asr Hospital in Zanjan from June to July 2021. Real-time PCR was used to diagnose COVID-19 in 76 hospitalized patients. A total of 38 patients were hospitalized in the internal medicine ward and another 38 people were admitted to the intensive care unit of the Vali-Asr Educational Hospital in Iran's Zanjan region. Lupus anticoagulant (LAC) detection was done using the dilute Russell viper venom time method, and tests for anticardiolipin (ACL) Abs, IgG and IgM, and anti-beta2 glycoprotein 1 Abs, IgG and IgM, were done on blood and plasma samples of linked patients using the enzyme-linked immunosorbent assay technique. SPSS 24 was used to analyze data. Our findings showed that the presence of LAC was associated with disease severity in COVID-19 patients (p = 0.001). However, there was no significant relationship between APL Abs and mortality in patients affected with COVID-19. The evaluation of APL Abs, particularly LAC, in COVID-19 patients appears to be helpful in predicting the severity of the disease.

Prevalence and Impact of Lupus Anticoagulant in Patients Receiving Extracorporeal Membrane Oxygenation

BACKGROUND

Monitoring of blood coagulation is essential in ECMO patients. We investigated the prevalence of lupus anticoagulant (LA) and its association with coagulation testing and hemostaseologic complications in patients treated with ECMO.

METHODS

This is a retrospective analysis including adult patients who received ECMO at a medical intensive care unit at the Medical University of Vienna. The primary outcome was the prevalence of LA. Secondary outcomes included conditions associated with LA positivity, rates of bleeding and thromboembolic events, as well as the proportions of aPTT and antiXa measurements within the target range.

RESULTS

Between 2013 and 2021 193 patients received ECMO, in 62 (32%) of whom LA diagnostics were performed. Twenty-two (35%) patients tested positive. LA positive patients had more frequently received VV ECMO (77.3% vs 34.3%; p = 0.002), were more frequently diagnosed with viral respiratory infections (SARS-CoV2: 45.5% vs 20%; p = 0.041, influenza virus: 22.7% vs 0%; p = 0.003), had a longer ECMO treatment duration (25 vs 10 days; p = 0.011) and a longer ICU stay (48 vs 25 days; p = 0.022), but similar rates of bleeding and thromboembolic events.

Longitudinal Analysis of Antiphospholipid Antibody Dynamics after Infection with SARS-CoV-2 or Vaccination with BNT162b2

Antiphospholipid antibodies (aPL) comprise a group of autoantibodies that reflect prothrombotic risk in antiphospholipid syndrome (APS) but may also be present in a small proportion of healthy individuals. They are often transiently elevated in infections, including SARS-CoV-2, and may also be associated with vaccine-induced autoimmunity. Therefore, we aimed to investigate the dynamics of aPL in COVID-19 patients and in individuals (healthcare professionals-HCPs) after receiving BNT162b2 vaccine and to compare aPL levels and positivity with those found in APS patients. We measured solid-phase identifiable aPL, including anticardiolipin (aCL), anti-β2 glycoprotein I (anti-β2GPI), and anti-prothrombin/phosphatidylserine (aPS/PT) antibodies in 58 HCPs before and after vaccination (at 3 weeks, 3, 6, and 9 months after the second dose, and 3 weeks after the third booster dose), in 45 COVID-19 patients hospitalized in the ICU, in 89 COVID-19 patients hospitalized in the non-ICU (at admission, at hospital discharge, and at follow-up), and in 52 patients with APS. The most frequently induced aPL in COVID-19 patients (hospitalized in non-ICU) were aCL (50.6% of patients had positive levels at at least one time point), followed by anti-β2GPI (21.3% of patients had positive levels at at least one time point). In 9/89 COVID-19 patients, positive aPL levels persisted for three months. One HCP developed aCL IgG after vaccination but the persistence could not be confirmed, and two HCPs developed persistent anti-β2GPI IgG after vaccination with no increase during a 1-year follow-up period. Solid-phase aPL were detected in 84.6% of APS patients, in 49.4% of COVID-19 patients hospitalized in the non-ICU, in 33.3% of COVID-19 patients hospitalized in the ICU, and in only 17.2% of vaccinated HCPs. aPL levels and multiple positivity were significantly lower in both infected groups and in vaccinated individuals compared with APS patients. In conclusion, BNT162b2 mRNA vaccine may have induced aPL in a few individuals, whereas SARS-CoV-2 infection itself results in a higher percentage of aPL induction, but the levels, persistence, and multiple positivity of aPL do not follow the pattern observed in APS.

Anti-cardiolipin IgG autoantibodies associate with circulating extracellular DNA in severe COVID-19

Whereas the detection of antiphospholipid autoantibodies (aPL) in COVID-19 is of increasing interest, their role is still unclear. We analyzed a large aPL panel in 157 patients with COVID-19 according to the disease severity. We also investigated a potential association between aPL and extracellular DNA (exDNA, n = 85) or circulating markers of neutrophil extracellular traps (NET) such as citrullinated histones H3 (CitH3, n = 49). A total of 157 sera of patients infected by SARS-CoV-2 were collected. A large aPL panel including lupus anticoagulant, anti-cardiolipin and anti-beta-2 glycoprotein I (IgG, IgM and IgA), anti-phosphatidylethanolamine IgA, anti-prothrombin (IgG and IgM) was retrospectively analyzed according to the disease severity. We found a total aPL prevalence of 54.8% with almost half of the cases having aCL IgG. Within an extended panel of aPL, only aCL IgG were associated with COVID-19 severity. Additionally, severe patients displayed higher CitH3 levels than mild patients. Interestingly, we highlighted a significant association between the levels of aCL IgG and exDNA only in aCL positive patients with severe disease. In conclusion, we showed a significant link between aPL, namely aCL IgG, and circulating exDNA in patients with severe form of COVID-19, that could exacerbate the thrombo-inflammatory state related to disease severity.

COVID-19 and the antiphospholipid syndrome

Coronavirus disease 2019 (COVID-19) has resulted in a global pandemic. Most COVID-19 patients are asymptomatic or have flu-like symptoms. However, around 15% of the patients may have severe disease, including unilateral or bilateral pneumonia with acute respiratory distress syndrome and progressive hypoxemia that may require mechanical ventilation assistance. A systemic inflammatory response syndrome occurs in the most severe forms of COVID-19, with multiorgan involvement which can be life threatening caused by a cytokine storm. Although what best characterizes COVID-19 are the manifestations of the respiratory system, it has been shown that it also acts at the cardiovascular level, producing coagulation abnormalities, which causes thrombotic events mainly in the arteries/arterioles, microcirculation and venous system, and potentially increased mortality risk. This multiorgan vascular disease overlaps with other known microangiopathies, such as thrombotic microangiopathy or paroxysmal nocturnal hemoglobinuria, where complement overactivation plays an important role in the pathophysiology of thrombosis. Furthermore, coagulopathy secondary to COVID-19 occurs in the context of an uncontrolled inflammatory response, reminiscent of APS, especially in its catastrophic form. This review summarizes the current knowledge regarding the relationship between COVID-19 and the APS.

Prevalence, characteristics and outcome of cardiac manifestations in critically-ill antiphospholipid syndrome patients

AIMS

Antiphospholipid syndrome (APS) is a rare autoimmune disease defined by thrombotic events occurring in patients with persistent antiphospholipid antibodies. Cardiac manifestations in critically-ill APS patients are poorly investigated. We conducted a study to assess the prevalence, the characteristics and the prognosis of cardiac manifestations in thrombotic APS patients admitted to intensive care unit (ICU).

METHODS AND RESULTS

A French, national, multicentre, retrospective study, conducted, from January 2000 to September 2018, including all APS patients admitted to 24 participating centres' ICUs with any new thrombotic (arterial, venous or microvascular) manifestation. Cardiac manifestations were defined as any new cardiac abnormalities relying on clinical examination, cardiac biomarkers, echocardiography, cardiac magnetic resonance (CMR) and coronarography. One hundred and thirty-six patients (female 72%) were included. Mean age at ICU admission was 46 ± 15years. Cardiac manifestations were present in 71 patients (53%). In patients with cardiac involvement, median left ventricular ejection fraction (LVEF) was 40% [28-55], troponin was elevated in 93% patients, coronary angiogram (n = 19, 27%) disclosing a coronary obstruction in 21%. CMR (n = 21) was abnormal in all cases, with late gadolinium enhancement in 62% of cases. Cardiac manifestations were associated with a non-significant increase of mortality (32% vs. 19%, p = 0.08). After 1-year follow-up, median LVEF was 57% [44-60] in patients with cardiac involvement.

CONCLUSION

Cardiac involvement is frequent in critically-ill thrombotic APS patients and may be associated to more severe outcome. Increased awareness on this rare cause of myocardial infarction with or without obstructive coronary artery is urgently needed.

Acquired hemophilia A secondary to SARS-CoV-2 pneumonia: a case report

The acquired hemophilia A (AHA) is a life-threatening condition. The incidence of AHA is extremely low, which requires a multidisciplinary approach to diagnosis and treatment. This is case report of 73-year-old man who presented with AHA secondary to severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) pneumonia. The patient had extensive skin bleeding and hematomas. In the coagulation screening tests activated partial thromboplastin time (APTT) was prolonged with normal prothrombin time (PT), which was indication for further investigation. The APTT in a mixing study with normal plasma did not correct so clotting factors inhibitors were suspected. With signs of bleeding, extremely low factor VIII (FVIII) activity (2%) and presence of FVIII inhibitors, AHA was diagnosed and treatment initiated. Patient was treated with factor eight inhibitor bypassing agent (FEIBA) for three days, followed by long-term corticosteroid and cyclophosphamide therapy. Malignant and autoimmune diseases as the most common causes of AHA were ruled out. The patient had a good response to therapy with gradual normalization of APTT and FVIII activity. To the best of our knowledge, the present case is the first reported case of de novo AHA after SARS-CoV-2 pneumonia. The diagnosis of AHA should be suspected in a patient with bleeding into the skin and mucous membranes without a previous personal and family history of bleeding, and with isolated prolonged APTT. It is important to investigate any isolated prolongation of APTT in cooperation with clinical laboratory experts.

Central Retinal Vein Occlusion Presumably Associated with Lupus Anticoagulant Induced by SARSCoV-2

PURPOSE

To report a case of unilateral central retinal vein occlusion (CRVO) and macular edema presumably associated with lupus anticoagulant (LA) induced by severe acute respiratory syndrome coronavirus 2 (SARS CoV-2).

METHOD

Case report.

RESULTS

A 32-year-old male patient presented to the emergency department with a 5-day history of blurry vision. He was diagnosed with a CRVO and macular edema. The only pathological finding was positive LA which could have been induced by his recent confirmed SARS CoV-2 infection. The patient's evolution was satisfactory after two injections of Intravitreal dexamethasone (Ozurdex®), with improvement in macular edema and visual acuity.

CONCLUSION

COVID-19 may be associated to retinal vascular occlusive disorders. Transient virus-induced LA might play a role in the pathogenesis of the thrombotic event.

Coagulopathy during COVID-19 infection: a brief review

The COVID-19 pandemic caused by SARS-CoV-2 continues to spread rapidly due to its virulence and ability to be transmitted by asymptomatic infected persons. If they are present, the symptoms of COVID-19 may include rhinorrhea (runny nose), headache, cough, and fever. Up to 5% of affected persons may experience more severe COVID-19 illness, including severe coagulopathy, acute respiratory distress syndrome (ARDS) characterized by respiratory failure that requires supplementary oxygen and mechanical ventilation, and multi-organ failure. Interestingly, clinical evidence has highlighted the distinction between COVID-19-associated coagulopathy (CAC) and disseminated intravascular coagulation (DIC). Patients with CAC exhibit different laboratory values than DIC patients for activated partial thromboplastin time (aPTT) and prothrombin time (PT) which may be normal or shortened, varying platelet counts, altered red blood cell morphology, unique bleeding complications, a lack of schistocytes in the peripheral blood, and no decrease in fibrinogen levels. In this review, we consider the search for 1) laboratory results that can diagnose or predict development of CAC, including serum levels of D-dimers, fibrinogen, interleukin-6 (IL-6) and the growth factor angiopoietin-2 (Ang-2), 2) mechanisms of CAC induction, and 3) novel therapeutic regimens that will successfully treat COVID-19 before development of CAC.

Increased risk of dialysis circuit clotting in hemodialysis patients with COVID-19 is associated with elevated FVIII, fibrinogen and D-dimers

INTRODUCTION

Severe COVID-19 infections increase the risk of thrombotic events and Intensive Care Units reported increased extracorporeal circuit clotting (ECC) in COVID-19 patients with acute kidney injury. We wished to determine whether hemodialysis (HD) patients with COVID-19 also have increased risk of circuit clotting.

METHODS

We reviewed coagulation studies and HD records, 4 weeks before and after COVID-19 polymerase chain reaction detection in HD patients between April 2020 and June 2021.

FINDINGS

Sixty-eight (33.5%) of 203 HD patients with COVID-19, 65% male, mean age 64.9 ± 15.3 years, experienced some circuit clotting, and no clotting recorded prior to positive test results. In those who experienced ECC, prothrombin, activated partial thromboplastin or thrombin times were not different, whereas median factor VIII (273 [168-419] vs. 166 [139-225] IU/dl, p < 0.001), D-dimers (2654 [1381-6019] vs. 1351 [786-2334] ng/ml, p < 0.05), and fibrinogen (5.6 ± 1.4 vs. 4.9 ± 1.4 g/L, p < 0.05) were greater. Antithrombin (94 [83-112] vs. 89 [84-103] IU/dl), protein C (102 [80-130] vs. 86 [76-106] IU/dl), protein S (65 [61-75] vs. 65 [52-79] IU/dl) and platelet counts (193 [138-243] vs. 174 [138-229] × 10⁹ /L) did not differ. On multivariable logistic analysis, circuit clotting was associated with log factor VIII (odds ratio [OR] 14.8 (95% confidence limits [95% CL] 1.12-19.6), p = 0.041), fibrinogen (OR 1.57 [95% CL 1.14-21.7], p = 0.006) and log D dimer (OR 4.8 [95% CL 1.16-12.5], p = 0.028).

DISCUSSION

Extracorporeal circuit clotting was increased within 4 weeks of testing positive for COVID-19. Clotting was associated with increased factor VIII, fibrinogen and D-dimer, suggesting that the risk of circuit clotting was related to the inflammatory response to COVID-19.

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.

The mechanistic basis linking cytokine storm to thrombosis in COVID-19

It is now well established that infection with SARS-CoV-2 resulting in COVID-19 disease includes a severely symptomatic subset of patients in whom an aggressive and/or dysregulated host immune response leads to cytokine storm syndrome (CSS) that may be further complicated by thrombotic events, contributing to the severe morbidity and mortality observed in COVID-19. This review provides a brief overview of cytokine storm in COVID-19, and then presents a mechanistic discussion of how cytokine storm affects integrated pathways in thrombosis involving the endothelium, platelets, the coagulation cascade, eicosanoids, auto-antibody mediated thrombosis, and the fibrinolytic system.

Platelet Dysregulation in the Pathobiology of COVID-19

Coronavirus disease 2019 (COVID-19) encompasses a broad spectrum of clinical manifestations caused by infection with severe acute respiratory syndrome coronavirus 2.Patients with severe disease present with hyperinflammation which can affect multiple organs which often include observations of microvascular and macrovascular thrombi. COVID-19 is increasingly recognized as a thromboinflammatory disease where alterations of both coagulation and platelets are closely linked to mortality and clinical outcomes. Although platelets are most well known as central mediators of hemostasis, they possess chemotactic molecules, cytokines, and adhesion molecules that are now appreciated as playing an important role in the regulation of immune response. This review summarizes the current knowledge of platelet alterations observed in the context of COVID-19 and their impact upon disease pathobiology.

Lupus anticoagulant associates with thrombosis in patients with COVID-19 admitted to intensive care units: A retrospective cohort study

Background

Thrombosis is a frequent and severe complication in patients with coronavirus disease 2019 (COVID‐19) admitted to the intensive care unit (ICU). Lupus anticoagulant (LA) is a strong acquired risk factor for thrombosis in various diseases and is frequently observed in patients with COVID‐19. Whether LA is associated with thrombosis in patients with severe COVID‐19 is currently unclear.

Objective

To investigate if LA is associated with thrombosis in critically ill patients with COVID‐19.

Patients/Methods

The presence of LA and other antiphospholipid antibodies was assessed in patients with COVID‐19 admitted to the ICU. LA was determined with dilute Russell's viper venom time (dRVVT) and LA‐sensitive activated partial thromboplastin time (aPTT) reagents.

Results

Of 169 patients with COVID‐19, 116 (69%) tested positive for at least one antiphospholipid antibody upon admission to the ICU. Forty (24%) patients tested positive for LA; of whom 29 (17%) tested positive with a dRVVT, 19 (11%) tested positive with an LA‐sensitive aPTT, and 8 (5%) tested positive on both tests. Fifty‐eight (34%) patients developed thrombosis after ICU admission. The odds ratio (OR) for thrombosis in patients with LA based on a dRVVT was 2.5 (95% confidence interval [CI], 1.1–5.7), which increased to 4.5 (95% CI, 1.4–14.3) in patients at or below the median age in this study (64 years). LA positivity based on a dRVVT or LA‐sensitive aPTT was only associated with thrombosis in patients aged less than 65 years (OR, 3.8; 95% CI, 1.3–11.4) and disappeared after adjustment for C‐reactive protein.

Conclusion

Lupus anticoagulant on admission is strongly associated with thrombosis in critically ill patients with COVID‐19, especially in patients aged less than 65 years.

Immunogenicity, safety, and antiphospholipid antibodies after SARS-CoV-2 vaccine in patients with primary antiphospholipid syndrome

Objective

Coronavirus disease 19 (COVID-19) has an increased risk of coagulopathy with high frequency of antiphospholipid antibodies (aPL). Recent reports of thrombosis associated with adenovirus-based vaccines raised concern that SARS-CoV-2 immunization in primary antiphospholipid syndrome (PAPS) patients may trigger clotting complications. Our objectives were to assess immunogenicity, safety, and aPL production in PAPS patients, after vaccinating with Sinovac-CoronaVac, an inactivated virus vaccine against COVID-19.

Methods

This prospective controlled phase-4 study of PAPS patients and a control group (CG) consisted of a two-dose Sinovac-CoronaVac (D0/D28) and blood collection before vaccination (D0), at D28 and 6 weeks after second dose (D69) for immunogenicity/aPL levels. Outcomes were seroconversion (SC) rates of anti-SARS-CoV-2 S1/S2 IgG and/or neutralizing antibodies (NAb) at D28/D69 in naïve participants. Safety and aPL production were also assessed.

Results

We included 44 PAPS patients (31 naïve) and 132 CG (108 naïve) with comparable age (p=0.982) and sex (p>0.999). At D69, both groups had high and comparable SC (83.9% vs. 93.5%, p=0.092), as well as NAb positivity (77.4% vs. 78.7%, p=0.440), and NAb-activity (64.3% vs. 60.9%, p=0.689). Thrombotic events up to 6 months or other moderate/severe side effects were not observed. PAPS patients remained with stable aPL levels throughout the study at D0 vs. D28 vs. D69: anticardiolipin (aCL) IgG (p=0.058) and IgM (p=0.091); anti-beta-2 glycoprotein I (aβ2GPI) IgG (p=0.513) and IgM (p=0.468).

Conclusion

We provided novel evidence that Sinovac-CoronaVac has high immunogenicity and safety profile in PAPS. Furthermore, Sinovac-CoronaVac did not trigger thrombosis nor induced changes in aPL production.

Persistent Antiphospholipid Antibodies Are Not Associated With Worse Clinical Outcomes in a Prospective Cohort of Hospitalised Patients With SARS-CoV-2 Infection

Objective

Patients with COVID-19 presented with an elevated prevalence of antiphospholipid antibodies (aPL) but the relationship with thrombosis is controversial. We analysed the persistence of aPL and their association with the clinical outcomes during hospitalisation in a cohort of COVID-19 patients.

Patients and Methods

We conducted a prospective study including consecutive hospitalised patients with COVID-19 from Hospital Clínic of Barcelona between March 28th and April 22nd, 2020. Clinical outcomes during hospitalisation were thrombosis, intensive care unit (ICU) admission, and severe ventilatory failure. We determined both criteria and non-criteria aPL. Of note, in those patients with a positive result in the first determination, a second sample separated by at least 12 weeks was drawn to test the persistence of aPL.

Results

One hundred and fifty-eight patients (59.5% men) with a mean age of 61.4 ± 14.9 years old were included. Thrombosis was present in 28 (17.7%) patients, severe respiratory failure in 47 (30.5%), and 30 (18.9%) patients were admitted to ICU. Sixteen (28.6%) patients were positive for the criteria aPL at both determinations and only two (3.6%) of them suffered from thrombosis during hospitalisations (both had aCL IgG). However, they presented with low titers of aCL. Of note, aPL were not related to thrombosis, ICU admission or severe respiratory failure.

Conclusion

Although aPL were prevalent in our cohort of hospitalised COVID-19 patients and they were persistent in half of tested patients, most determinations were at low titers and they were not related to worse clinical outcomes.

ESC guidance for the diagnosis and management of cardiovascular disease during the COVID-19 pandemic: part 2-care pathways, treatment, and follow-up

AIMS

Since its emergence in early 2020, the novel severe acute respiratory syndrome coronavirus 2 causing coronavirus disease 2019 (COVID-19) has reached pandemic levels, and there have been repeated outbreaks across the globe. The aim of this two part series is to provide practical knowledge and guidance to aid clinicians in the diagnosis and management of cardiovascular (CV) disease in association with COVID-19.

METHODS AND RESULTS

A narrative literature review of the available evidence has been performed, and the resulting information has been organized into two parts. The first, which was reported previously, focused on the epidemiology, pathophysiology, and diagnosis of CV conditions that may be manifest in patients with COVID-19. This second part addresses the topics of: care pathways and triage systems and management and treatment pathways, both of the most commonly encountered CV conditions and of COVID-19; and information that may be considered useful to help patients with CV disease (CVD) to avoid exposure to COVID-19.

CONCLUSION

This comprehensive review is not a formal guideline but rather a document that provides a summary of current knowledge and guidance to practicing clinicians managing patients with CVD and COVID-19. The recommendations are mainly the result of observations and personal experience from healthcare providers. Therefore, the information provided here may be subject to change with increasing knowledge, evidence from prospective studies, and changes in the pandemic. Likewise, the guidance provided in the document should not interfere with recommendations provided by local and national healthcare authorities.

Solid Phase Assays for Antiphospholipid Antibodies

The diagnosis of antiphospholipid syndrome (APS) relies on the detection of circulating antiphospholipid antibodies (aPL). Currently, lupus anticoagulant (LA), anticardiolipin (aCL), and anti-β2-glycoprotein I antibodies (aβ2GPI) IgG or IgM are the laboratory criteria if persistently present over time. As aCL and aβ2GPI are two out of the three laboratory criteria, the detection of aPL by solid phase assays is an essential step in the diagnosis of APS. Advancement has been made to resolve some of the methodological challenges of aCL and aβ2GPI assays by providing guidelines how to measure aPL, as well as to gain a better understanding of their diagnostic role. However, solid phase assays for aCL and aβ2GPI still show substantive inter-assay differences, resulting in disagreement concerning positive/negative results, but also differences in titer of antibodies. This hampers the semiquantitative classification into low-medium-high positivity. The non-criteria aPL, such as antibodies against the domain one of β2GPI and anti-phosphatidylserine/prothrombin antibodies (aPS/PT) have roles in confirming the risk in APS, and can be useful, especially in patients with incomplete antibody profiles.

Engineering viral genomics and nano-liposomes in microfluidic platforms for patient-specific analysis of SARS-CoV-2 variants

New variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are continuing to spread globally, contributing to the persistence of the COVID-19 pandemic. Increasing resources have been focused on developing vaccines and therapeutics that target the Spike glycoprotein of SARS-CoV-2. Recent advances in microfluidics have the potential to recapitulate viral infection in the organ-specific platforms, known as organ-on-a-chip (OoC), in which binding of SARS-CoV-2 Spike protein to the angiotensin-converting enzyme 2 (ACE2) of the host cells occurs. As the COVID-19 pandemic lingers, there remains an unmet need to screen emerging mutations, to predict viral transmissibility and pathogenicity, and to assess the strength of neutralizing antibodies following vaccination or reinfection. Conventional detection of SARS-CoV-2 variants relies on two-dimensional (2-D) cell culture methods, whereas simulating the micro-environment requires three-dimensional (3-D) systems. To this end, analyzing SARS-CoV-2-mediated pathogenicity via microfluidic platforms minimizes the experimental cost, duration, and optimization needed for animal studies, and obviates the ethical concerns associated with the use of primates. In this context, this review highlights the state-of-the-art strategy to engineer the nano-liposomes that can be conjugated with SARS-CoV-2 Spike mutations or genomic sequences in the microfluidic platforms; thereby, allowing for screening the rising SARS-CoV-2 variants and predicting COVID-19-associated coagulation. Furthermore, introducing viral genomics to the patient-specific blood accelerates the discovery of therapeutic targets in the face of evolving viral variants, including B1.1.7 (Alpha), B.1.351 (Beta), B.1.617.2 (Delta), c.37 (Lambda), and B.1.1.529 (Omicron). Thus, engineering nano-liposomes to encapsulate SARS-CoV-2 viral genomic sequences enables rapid detection of SARS-CoV-2 variants in the long COVID-19 era.

COVID-19: a trigger for severe thrombotic microangiopathy in a patient with complement gene variant

The evidence regarding thrombotic microangiopathy (TMA) related to Coronavirus Infectious Disease 2019 (COVID-19) in patients with complement gene mutations as a cause of acute kidney injury (AKI) are limited. We presented the case of a 23-year-old male patient admitted with an asymptomatic form of COVID-19, but with uncontrolled hypertension and AKI. Kidney biopsy showed severe lesions of TMA. In evolution patient had persistent microangiopathic hemolytic anemia, decreased level of haptoglobin and increased LDH level. Decreased complement C3 level and the presence of schistocytes were found for the first time after biopsy. Kidney function progressively decreased and the patient remained hemodialysis dependent. Complement work-up showed a heterozygous variant with unknown significance in complement factor I (CFI) c.-13G>A, affecting the 5' UTR region of the gene. In addition, the patient was found to be heterozygous for the complement factor H (CFH) H3 haplotype (involving the rare alleles of c.-331C>T, Q672Q and E936D polymorphisms) reported as a risk factor of atypical hemolytic uremic syndrome. This case of AKI associated with severe TMA and secondary hemolytic uremic syndrome highlights the importance of genetic risk modifiers in the alternative pathway dysregulation of the complement in the setting of COVID-19, even in asymptomatic forms.

COVID-19 coagulopathy and antiphospholipid syndrome

The presence of thrombotic events in COVID-19 patients has been described since the beginning of the pandemic. This association has been confirmed in most of the reported studies. Autopsy reports have shown that most thromboses are located in the lung, although they have also been observed in other organs such as the skin and kidneys. SARS-CoV2 infection induces a generalized prothrombotic state, which is attributed to a combination of factors such as hypoxia, excess cellular apoptosis, and mainly to overactivation of the immune system. Among immune-mediated prothrombotic situations, antiphospholipid syndrome (APS) stands out. Recurrent thrombotic events are observed in APS in the presence of antiphospholipid antibodies (aPL). There are numerous studies that report high prevalence of aPL in patients with COVID-19 infection. However, the results show discrepancies in the data on the prevalence of aPL, and its role in the pathogenesis of thrombosis in these patients. This could be due to the heterogeneity of the detection procedures for aPL or to transient elevations of non-pathogenic aPL levels in the context of infection. In this review we try to clarify the role of aPL in COVID-19 infection, and attempt to answer the question of whether it is a coagulopathy of its own, or secondary to APS.

Anticardiolipin Autoantibodies as Useful Biomarkers for the Prediction of Mortality in Septic Patients

Background. The detection of antiphospholipid antibodies (aPL) is of interest because of their importance in the pathogenesis of arterial or venous thrombosis. They could be a “second hit” of an inflammatory event such as infection. The aim of our study was to assess the performance of antiphospholipid antibody biomarker to predict in-hospital mortality in intensive care unit (ICU) septic patients. Methods. We conducted a prospective single-center observational study including consecutive critically ill septic adults admitted to the intensive care unit. Clinical and laboratory data including enzyme-linked immunosorbent assay for antiphospholipid antibodies (anticardiolipin (aCL), antiphosphatidylserine (aPS)) were obtained. Blood samples were collected on days 1, 3, 5, 8, and 10 of hospitalization. The primary study endpoint was ICU mortality defined as death before ICU discharge. Secondary end points included correlation between SOFA score and biological parameters. Results. A total of 53 patients were enrolled. 18.8% of patients were aPL positive. In-hospital mortality rate was 60%. Multivariate analysis showed that age and aCL at days 3 and 5 along with SOFA at day 3 were independent outcome predictors. A significant positive correlation existed between SOFA at days 3, 5, and 8 and antiphospholipid antibody concentrations. Conclusions. Our data showed that antiphospholipid was useful biomarkers for the prediction of mortality in critically ill septic patients. We found a positive correlation between SOFA score and antiphospholipid antibodies.