Systematic review of case reports of antiphospholipid syndrome following infection

Lipid-binding antiphospholipid antibodies: significance for pathophysiology and diagnosis of the antiphospholipid syndrome

The antiphospholipid syndrome (APS) is an autoimmune disease characterized by the presence of pathogenic antiphospholipid antibodies (aPL). Since approximately 30 years ago, lipid-binding aPL, which do not require a protein cofactor, have been regarded as irrelevant for APS pathogenesis even though anticardiolipin are a diagnostic criterion of APS. In this review, we will summarize the available evidence from in vitro studies, animal models, and epidemiologic studies, which suggest that this concept is no longer tenable. Accordingly, we will only briefly touch on the role of other aPL in APS. This topic has been amply reviewed in detail elsewhere. We will discuss the consequences for laboratory diagnostics and future research required to resolve open questions related to the pathogenic role of different aPL specificities.

Muscle hypertrophy following acquired neurogenic injury: systematic review and analysis of existing literature

OBJECTIVES

Neurogenic muscle hypertrophy (NMH) is a rare condition characterized by focal muscle hypertrophy caused by chronic partial nervous injury. Given its infrequency, underlying mechanisms remain poorly understood. Inspired by two clinical cases, we conducted a systematic review to gain insights into the different aspects of NMH.

METHODS

We systematically searched online databases up until May 30, 2023, for reports of muscle hypertrophy attributed to acquired neurogenic factors. We conducted an exploratory analysis to identify commonly associated features. We also report two representative clinical cases.

RESULTS

Our search identified 63 reports, describing 93 NMH cases, to which we added our two cases. NMH predominantly affects patients with compressive radiculopathy (68.4%), negligible muscular weakness (93.3%), and a chronic increase in muscle bulk. A striking finding in most neurophysiological studies (60.0%) is profuse spontaneous discharges, often hindering the analysis of voluntary traces. Some patients exhibited features consistent with more significant muscle damage, including higher creatine phosphokinase levels, muscle pain, and inflammatory muscle infiltration. These patients are sometimes referred to in literature as "focal myositis." Treatment encompassed corticosteroid, Botulinum Toxin A, decompressive surgery, antiepileptic medications, and nerve blocks, demonstrating varying degrees of efficacy. Botulinum Toxin A yielded the most favorable response in terms of reducing spontaneous discharges.

INTERPRETATION

This systematic review aims to provide a clear description and categorization of this uncommon presentation of an often-overlooked neurological disorder. Though questions remain about the underlying mechanism, evidence suggests that aberrant fiber overstimulation along with increased workload that promotes focal damage may result in muscle hypertrophy. This may serve as a guide for therapeutic interventions.

Exploring the impact of acute viral exposure on clinical characteristics and antibody profiles in antiphospholipid syndrome: a study in CAPSTONE

The relationship between antiphospholipid syndrome (APS) and acute viral infection, such as SARS-CoV-2, is unclear. This study aims to assess symptoms, antiphospholipid antibody (aPL) fluctuations, and complication risks in APS patients infected with SARS-CoV-2. APS patients from Peking Union Medical College Hospital during the COVID-19 outbreak (October-December 2022) were included. Age- and gender-matched APS patients without infection served as controls. Data on demographics, symptoms, treatments, and serum aPL levels were analyzed. Of 234 APS patients, 107 (45.7%) were infected with SARS-CoV-2. Typical symptoms included high fever (81.3%), cough/expectoration (70.1%), and pharyngalgia (52.3%). Age- and gender-based matching selected 97 patients in either infected or uninfected group. After infection, anti-β-2-glycoprotein I-IgG (aβ2GP1-IgG) increased from 4.14 to 4.18 AU/ml, aβ2GP1-IgM decreased from 9.85 to 7.38 AU/ml, and anticardiolipin-IgA (aCL-IgA) significantly increased with a median remaining at 2.50 APLU/ml. Lupus anticoagulants and other aPLs remained stable. Arterial thrombosis incidence increased from 18 (18.6%) to 21 (21.6%), while venous thrombosis incidence did not change. Additionally, 7 (6.5%) patients presented either new-onset or worsening thrombocytopenia, characterized by a significant decline in platelet count (no less than 10 × 109/L) within two weeks of SARS-CoV-2 infection, all of which recovered within 2 weeks. Acute SARS-CoV-2 infection may induce or worsen thrombocytopenia but does not substantially increase thrombotic events in APS. The process of SARS-CoV-2 infection was related to mild titer fluctuation of aβ2GP1-IgG, aβ2GP1-IgM and aCL-IgA in APS patients, necessitating careful monitoring and management.

A Systematic Review on the Diagnostic Value of Fibroblast Activation Protein Inhibitor PET/CT in Genitourinary Cancers

In contemporary oncologic diagnostics, molecular imaging modalities are pivotal for precise local and metastatic staging. Recent studies identified fibroblast activation protein as a promising target for molecular imaging across various malignancies. Therefore, we aimed to systematically evaluate the current literature on the utility of fibroblast activation protein inhibitor (FAPI) PET/CT for staging patients with genitourinary malignancies. Methods: A systematic Embase and Medline search was conducted, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) process, on August 1, 2023. Relevant publications reporting on the diagnostic value of FAPI PET/CT in genitourinary malignancies were identified and included. Studies were critically reviewed using a modified version of a tool for quality appraisal of case reports. Study results were summarized using a narrative approach. Results: We included 22 retrospective studies with a cumulative total of 69 patients, focusing on prostate cancer, urothelial carcinoma of the bladder and of the upper urinary tract, renal cell carcinoma, and testicular cancer. FAPI PET/CT was able to visualize both local and metastatic disease, including challenging cases such as prostate-specific membrane antigen (PSMA)-negative prostate cancer. Compared with radiolabeled 18F-FDG and PSMA PET/CT, FAPI PET/CT showed heterogeneous performance. In selected cases, FAPI PET/CT demonstrated superior tumor visualization (i.e., better tumor-to-background ratios and visualization of small tumors or metastatic deposits visible in no other way) over 18F-FDG PET/CT in detecting local or metastatic disease, whereas comparisons with PSMA PET/CT showed both superior and inferior performances. Challenges in FAPI PET/CT arise from physiologic urinary excretion of most FAPI radiotracers, hindering primary-lesion visualization in the bladder and upper urinary tract, despite generally providing high tumor-to-background ratios. Conclusion: The current findings suggest that FAPI PET/CT may hold promise as a future tool to aid clinicians in detecting genitourinary malignancies. Given the substantial heterogeneity among the included studies and the limited number of patients, caution in interpreting these findings is warranted. Subsequent prospective and comparative investigations are anticipated to delve more deeply into this innovative imaging modality and elucidate its role in clinical practice.

New Directions in Infection-Associated Ischemic Stroke

The relationship between infections and stroke has not been fully characterized, probably delaying the development of specific treatments. This narrative review addresses mechanisms of stroke linked to infections, including hypercoagulability, endothelial dysfunction, vasculitis, and impaired thrombolysis. SARS-CoV-2, the virus that causes COVID-19, may promote the development of stroke, which may represent its most severe neurological complication. The development of specific therapies for infection-associated stroke remains a profound challenge. Perhaps the most important remaining issue is the distinction between infections that trigger a stroke versus infections that are truly incidental. This distinction likely requires the establishment of appropriate biomarkers, candidates of which are elevated levels of fibrin D-dimer and anticardiolipin/antiphospholipid antibodies. These candidate biomarkers might have potential use in identifying pathogenic infections preceding stroke, which is a precursor to establishing specific therapies for this syndrome.

CDC Laboratory Recommendations for Syphilis Testing, United States, 2024

This report provides new CDC recommendations for tests that can support a diagnosis of syphilis, including serologic testing and methods for the identification of the causative agent Treponema pallidum. These comprehensive recommendations are the first published by CDC on laboratory testing for syphilis, which has traditionally been based on serologic algorithms to detect a humoral immune response to T. pallidum. These tests can be divided into nontreponemal and treponemal tests depending on whether they detect antibodies that are broadly reactive to lipoidal antigens shared by both host and T. pallidum or antibodies specific to T. pallidum, respectively. Both types of tests must be used in conjunction to help distinguish between an untreated infection or a past infection that has been successfully treated. Newer serologic tests allow for laboratory automation but must be used in an algorithm, which also can involve older manual serologic tests. Direct detection of T. pallidum continues to evolve from microscopic examination of material from lesions for visualization of T. pallidum to molecular detection of the organism. Limited point-of-care tests for syphilis are available in the United States; increased availability of point-of-care tests that are sensitive and specific could facilitate expansion of screening programs and reduce the time from test result to treatment. These recommendations are intended for use by clinical laboratory directors, laboratory staff, clinicians, and disease control personnel who must choose among the multiple available testing methods, establish standard operating procedures for collecting and processing specimens, interpret test results for laboratory reporting, and counsel and treat patients. Future revisions to these recommendations will be based on new research or technologic advancements for syphilis clinical laboratory science.

Deep proteomic analysis of obstetric antiphospholipid syndrome by DIA-MS of extracellular vesicle enriched fractions

Proteins in the plasma/serum mirror an individual's physiology. Circulating extracellular vesicles (EVs) proteins constitute a large portion of the plasma/serum proteome. Thus, deep and unbiased proteomic analysis of circulating plasma/serum extracellular vesicles holds promise for discovering disease biomarkers as well as revealing disease mechanisms. We established a workflow for simple, deep, and reproducible proteome analysis of both serum large and small EVs enriched fractions by ultracentrifugation plus 4D-data-independent acquisition mass spectrometry (4D-DIA-MS). In our cohort study of obstetric antiphospholipid syndrome (OAPS), 4270 and 3328 proteins were identified from large and small EVs enriched fractions respectively. Both of them revealed known or new pathways related to OAPS. Increased levels of von Willebrand factor (VWF) and insulin receptor (INSR) were identified as candidate biomarkers, which shed light on hypercoagulability and abnormal insulin signaling in disease progression. Our workflow will significantly promote our understanding of plasma/serum-based disease mechanisms and generate new biomarkers.

Ischemic Stroke with Positive Antiphospholipid Antibodies in Bloom Syndrome: A Case Report

OBJECTIVE

Bloom syndrome is a chromosomal breakage disorder associated with immune deficiency, characterized by short stature, predisposition to early-onset cancer, and immune defects. Currently, there have been no reports of acute cerebral infarction in patients with Bloom syndrome. Here, we report a case of Bloom syndrome complicated by elevated antiphospholipid antibodies and acute cerebral infarction.

MATERIALS AND METHODS

A 23-year-old male with a known genetic diagnosis of Bloom syndrome was admitted to the Respiratory Department due to pulmonary aspergillosis. The patient experienced sudden dizziness, and subsequent cranial MRI revealed a newly developed infarction in the right cerebellar hemisphere.

RESULTS

Six days later, the patient presented with sudden right visual field loss, and a repeat cranial MRI showed new infarctions in the left occipital and temporal lobes. Positive lupus anticoagulant and prolonged activated partial thromboplastin time suggested elevated antiphospholipid antibodies causing thrombus formation. Unfortunately, anticoagulant treatment was not administered due to recurrent hemoptysis.

CONCLUSION

This study reports the first case of a Bloom syndrome patient with elevated antiphospholipid antibodies and acute cerebral infarction, suggesting that the immune and coagulation abnormalities caused by Bloom syndrome may contribute to the development of acute cerebral infarction.

Systematic review of TNFα-induced paradoxical psoriasis: Treatment outcomes of switching to alternative biologic therapies in inflammatory bowel disease patients

OBJECTIVES

The objective of this systematic review was to evaluate the efficacies of different biologic therapies in treating tumor necrosis factor-alpha (TNFα)-induced paradoxical psoriasis (PXP) and controlling inflammatory bowel disease (IBD) symptoms.

METHODS

We conducted a literature search of the Ovid EMBASE, Ovid Medline, Web of Science Core Collection, and Cochrane Central Register of Controlled Trials databases from their inception to October 3, 2021. We considered all peer-reviewed, randomized controlled trials, chart reviews, and observational studies that discussed the TNFα-induced PXP treatment outcomes in IBD patients of switching to different biologic therapies.

RESULTS

Switching to ustekinumab (UST) resulted in complete or partial resolution of TNFα-induced PXP in 83.1% of patients (74 out of 89 patients), while switching to either vedolizumab (VDZ) or secukinumab led to complete resolution in 100% of patients (eight out of eight patients). Approximately 75.4% of patients who were switched to UST remained in IBD remission, 4.6% in partial remission, and 20.0% in the flare of IBD.

CONCLUSIONS

UST has sufficient data to demonstrate the efficacy in treating TNFα-induced PXP and controlling IBD symptoms concurrently. More data is needed to validate the efficacies of VDZ and SEC in treating TNFα-induced PXP in IBD patients.

Antiphospholipid Antibodies and Vascular Thrombosis in Patients with Severe Forms of COVID-19

Antiphospholipid antibodies (aPLA) are a laboratory criterion for the classification of antiphospholipid syndrome (APS) and are known to cause clinical symptoms such as vascular thrombosis or obstetric complications. It is suggested that aPLA may be associated with thromboembolism in severe COVID-19 cases. Therefore, we aimed to combine clinical data with laboratory findings of aPLA at four time points (admission, worsening, discharge, and 3-month follow-up) in patients hospitalized with COVID-19 pneumonia. In 111 patients with COVID-19 pneumonia, current and past history of thrombosis and pregnancy complications were recorded. Nine types of aPLA were determined at four time points: anticardiolipin (aCL), anti-β2-glycoprotein I (anti- β2GPI), and antiphosphatidylserine/prothrombin (aPS/PT) of the IgM, IgG, or IgA isotypes. During hospitalization, seven patients died, three of them due to pulmonary artery thromboembolism (none were aPLA positive). Only one of the five who developed pulmonary artery thrombosis was aPLA positive. Out of 9/101 patients with a history of thrombosis, five had arterial thrombosis and none were aPLA positive at admission and follow-up; four had venous thrombosis, and one was aPLA positive at all time points (newly diagnosed APS). Of these 9/101 patients, 55.6% were transiently aPLA positive at discharge only, compared to 26.1% without a history of thrombosis (p = 0.041). Patients with severe forms of COVID-19 and positive aPLA should receive the same dose and anticoagulant medication regimen as those with negative aPLA because those antibodies are mostly transiently positive and not linked to thrombosis and fatal outcomes.

Phenotype and disease course differences in monogenic and sporadic childhood lupus

OBJECTIVE

To report the differences in phenotypic characteristics, disease course, and outcome in monogenic and sporadic childhood lupus (SC-lupus) from a single tertiary childhood lupus clinic.

METHODS

A descriptive, observational, cross-sectional study was conducted. Data were retrospectively collected at the last follow-up visit on patients with monogenic lupus proven by genetic variants and SC-lupus seen between June 1997 and July 2022. SC-lupus patients were selected by systematic sampling from lupus patients presenting to our lupus clinic; the first patient was chosen randomly, and the subsequent patients were chosen at intervals of three. Data comprised the clinical and laboratory findings, disease activity using the SLEDAI, and damage measured by the pSDI.

RESULTS

A total of 54 patients with a median disease duration of 6.8 (IQR 3.5-10.5) years were included. There were 27 patients with monogenic lupus and 27 patients with SC-lupus, with a median age at disease onset of 3.5 (IQR 1.0-6.0), and 9.5 (IQR 7.0-11.8), respectively. (p < 0.05). The rate of consanguinity and family history of lupus were higher in monogenic lupus patients. The two groups were comparable. However, monogenic lupus patients showed more gastrointestinal tract symptoms, and failure to thrive (p < 0.05). They also had more infections. The frequency of the autoantibody profile was higher in monogenic lupus patients. Belimumab was more frequently used in monogenic lupus while rituximab in SC-lupus patients. Monogenic lupus patients had a higher mean SLEDAI, but statistically, it was insignificant. Patients with monogenic lupus had greater disease damage, with a higher mean pSDI and a higher mortality rate (p < 0.05).

CONCLUSION

Patients with monogenic lupus are likely to have an early disease onset and a strong family history of lupus, as well as a guarded prognosis, which is likely due to the disease's severity and frequent infections. These differences may be related to the high consanguinity rate and underlying genetic variants.

Post-viral idiopathic purpura fulminans is associated with inherited thrombophilia and anti-cardiolipin antibodies

Introduction

Idiopathic purpura fulminans (IPF) is a rare and severe coagulation disorder, associated with transient anti-protein S (anti-PS) antibodies in the context of post-viral infection such as varicella. Anti-protein S antibodies are frequently found in the context of varicella, in contrast with the rarity of IPF. Other factors such as anti-phospholipid antibodies (APL) and inherited thrombophilia may be associated with severe vascular complication.

Method

This is an ancillary study of a French multicenter retrospective series and systematic review of literature. We analyzed patients who were tested for inherited thrombophilia, namely antithrombin, protein C, protein S deficiency; prothrombin gene G20210A polymorphism (FII:G20210A),Factor V R506Q polymorphism (FV:R506Q); and/or for APL (lupus anticoagulant (LA), anti-cardiolipin antibodies (ACL), or anti-beta 2-GPI antibodies (Aβ2GP1).

Results

Among the 25 patients tested for inherited thrombophilia, 7 (28%) had positive results. Three had FV R506Q, two FII:G20210A, one compound heterozygote FV:R506Q associated to FII:G20210A, and one protein C deficiency. APL testing was performed in 32 patients. It was positive in 19 patients (59%): 17 ACL (53%), 5 LA (16%), 4 Aβ2GP1 (13%). The risk of severe complications was not associated with presence of inherited thrombophilia or APL presence, with RR: 0.8 [95% CI: 0.37-1.71], p = 1 and RR: 0.7 [95% CI: 0.33-1.51], p = 0.39, respectively. We found a high prevalence of inherited thrombophilia or APL in a population of patients with IPF. However, we do not find an association with the occurrence of severe vascular complications or venous thromboembolism.

A tumor-selective adenoviral vector platform induces transient antiphospholipid antibodies, without increased risk of thrombosis, in phase 1 clinical studies

Tumor-selective viruses are a novel therapeutic approach for treating cancer. Tumor-Specific Immuno Gene Therapy (T-SIGn) vectors are tumor-selective adenoviral vectors designed to express immunomodulatory transgenes. Prolonged activated partial thromboplastin time (aPTT), associated with the presence of antiphospholipid antibodies (aPL), has been observed in patients with viral infections, and following administration of adenovirus-based medicines. aPL may be detected as lupus anticoagulant (LA), anti-cardiolipin (aCL) and/or anti-beta 2 glycoprotein antibodies (aβ2GPI). No subtype alone is definitive for development of clinical sequalae, however, patients who are 'triple positive' have a greater thrombotic risk. Additionally, isolated aCL and aβ2GPI IgM do not appear to add value in thrombotic association to aPL positivity, rather IgG subtypes must also be present to confer an increased risk. Here we report induction of prolonged aPTT and aPL in patients from eight Phase 1 studies who were treated with adenoviral vectors (n = 204). Prolonged aPTT (≥ Grade 2) was observed in 42% of patients, with a peak at 2-3 weeks post-treatment and resolution within ~ 2 months. Among patients with aPTT prolongation, LA, but not aCL IgG nor aβ2GPI IgG, was observed. The transience of the prolongation and discordance between positive LA and negative aCL/aβ2GPI IgG assays is not typical of a prothrombotic state. Among the patients with prolonged aPTT there was no evidence of an increased rate of thrombosis. These findings elucidate the relationship between viral exposure and aPL in the context of clinical trials. They suggest a framework in which hematologic changes can be monitored in patients receiving similar treatments.Clinical trial registration:NCT02028442, NCT02636036, NCT02028117, NCT03852511, NCT04053283, NCT05165433, NCT04830592, NCT05043714.

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.

Autoimmune complications of COVID-19 and potential consequences for long-lasting disease syndromes

The latest WHO report determined the increasing diversity within the CoV-2 omicron and its descendent lineages. Some heavily mutated offshoots of BA.5 and BA.2, such as BA.4.6, BF.7, BQ.1.1, and BA.2.75, are responsible for about 20% of infections and are spreading rapidly in multiple countries. It is a sign that Omicron subvariants are now developing a capacity to be more immune escaping and may contribute to a new wave of COVID-19. Covid-19 infections often induce many alterations in human physiological defense and the natural control systems, with exacerbated activation of the inflammatory and homeostatic response, as for any infectious diseases. Severe activation of the early phase of hemostatic components, often occurs, leading to thrombotic complications and often contributing to a lethal outcome selectively in certain populations. Development of autoimmune complications increases the disease burden and lowers its prognosis. While the true mechanism still remains unclear, it is believed to mainly be related to the host autoimmune responses as demonstrated, only in some patients suffering from the presence of autoantibodies that worsens the disease evolution. In fact in some studies the development of autoantibodies to angiotensin converting enzyme 2 (ACE2) was identified, and in other studies autoantibodies, thought to be targeting interferon or binding to annexin A1, or autoantibodies to phospholipids were seen. Moreover, the occurrence of autoimmune heparin induced thrombocytopenia has also been described in infected patients treated with heparin for controlling thrombogenicity. This commentary focuses on the presence of various autoantibodies reported so far in Covid-19 diseases, exploring their association with the disease course and the durability of some related symptoms. Attempts are also made to further analyze the potential mechanism of actions and link the presence of antibodies with pathological complications.

Thromboembolic complications of Mycoplasma pneumoniae pneumonia in children

BACKGROUND

Thromboembolism is less common in children than in adults, but it is frequently associated with Mycoplasma pneumoniae infection in many cases. This study aimed to investigate the clinical characteristics of pediatric M. pneumoniae pneumonia complicated with thromboembolism.

METHODS

Hospitalized patients with M. pneumoniae pneumonia complicated by thromboembolism were enrolled from January 2012 to December 2021 in Beijing Children's Hospital, Capital Medical University, China. The data on clinical manifestations, laboratory tests, and treatment were evaluated.

RESULTS

A total of 49 cases were enrolled, with a mean age of 7.9 years old, including 27 boys and 22 girls. Consolidation of pulmonary lobe or segment was observed in 95.9% (47/49) of the cases, whereas interstitial change was found only in two patients; 85.7% (42/49) of patients had pleural effusion. Pulmonary vascular thromboembolism was most common in 35 patients, whereas 13 cases had thromboembolism of multiple anatomic sites. The levels of C-reaction protein, lactate dehydrogenase, and erythrocyte sedimentation rate were all increased, with a mean value of 54.08 ± 52.27 g/L, 451.12 ± 218.76 U/L, 43.40 ± 29.43 mm/h, respectively. Blood coagulation test showed that all 49 patients had elevated D-dimer values (median 3.81 ng/ml, range, 0.34-48 ng/ml) and normal PT. aPTT.LA was positive in 74.3% (26/35) of the cases. aCL-IgM was positive in 66.7% (26/39) of the cases. aβ2GPI-IgM was positive in 79.4% (27/34) of the cases. The prognosis was generally good in this group.

CONCLUSION

Pulmonary arteriovenous thromboembolism is the most common thromboembolism complicated in MPP, and cerebral artery embolism and cardiac thrombosis are common in extrapulmonary thromboembolism. In the cases of MPP with thromboembolic complications, pulmonary consolidation with pleural effusion is the main characteristic. About two thirds of the cases are positive for antiphospholipid antibodies.

Dedifferentiated Low-Grade Osteosarcoma, Outcome with or Without Chemotherapy: A Systematic Review

The treatment of low-grade osteosarcomas is surgical resection with wide margins. In instances of dedifferentiation, a therapeutic paradigm similar to that of conventional high-grade osteosarcoma has not been adequately evaluated in these neoplasms. The main objective of this review was to define whether the addition of chemotherapy to surgical treatment has an impact on the survival of patients with dedifferentiated low-grade osteosarcomas. Secondary objectives were to observe the degree of histological response to neoadjuvant chemotherapy and to describe the percentage of de novo dedifferentiation. A systematic search of articles including dedifferentiated low-grade osteosarcomas, published between 1980 and 2022 was carried out in the PubMed, Cochrane and Scielo databases. A qualitative synthesis of the results was performed. Twenty-three articles comprising 117 patients were included. The survival of patients treated with surgery alone and surgery with chemotherapy was not statistically significant between the two groups. A good histological response was seen in 20% of specimens treated with neoadjuvant chemotherapy. De novo dedifferentiation was seen in approximately a fifth of low-grade osteosarcomas. The evidence available suggests that the addition of chemotherapy does not have an impact on the survival of patients with low-grade dedifferentiated osteosarcomas.

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.

Antiphospholipid antibodies in patients with stroke during COVID-19: A role in the signaling pathway leading to platelet activation

Background

Several viral and bacterial infections, including COVID-19, may lead to both thrombotic and hemorrhagic complications. Previously, it has been demonstrated an "in vitro" pathogenic effect of "antiphospholipid" antibodies (aPLs), which are able to activate a proinflammatory and procoagulant phenotype in monocytes, endothelial cells and platelets. This study analyzed the occurrence of aPL IgG in patients with acute ischemic stroke (AIS) during COVID-19, evaluating the effect of Ig fractions from these patients on signaling and functional activation of platelets.

Materials and methods

Sera from 10 patients with AIS during COVID-19, 10 non-COVID-19 stroke patients, 20 COVID-19 and 30 healthy donors (HD) were analyzed for anti-cardiolipin, anti-β2-GPI, anti-phosphatidylserine/prothrombin and anti-vimentin/CL antibodies by ELISA. Platelets from healthy donors were incubated with Ig fractions from these patients or with polyclonal anti-β2-GPI IgG and analyzed for phospho-ERK and phospho-p38 by western blot. Platelet secretion by ATP release dosage was also evaluated.

Results

We demonstrated the presence of aPLs IgG in sera of patients with AIS during COVID-19. Treatment with the Ig fractions from these patients or with polyclonal anti-β2-GPI IgG induced a significant increase of phospho-ERK and phospho-p38 expression. In the same vein, platelet activation was supported by the increase of adenyl nucleotides release induced by Ig fractions.

Conclusions

This study demonstrates the presence of aPLs in a subgroup of COVID-19 patients who presented AIS, suggesting a role in the mechanisms contributing to hypercoagulable state in these patients. Detecting these antibodies as a serological marker to check and monitor COVID-19 may contribute to improve the risk stratification of thromboembolic manifestations in these patients.

A Patient with Severe Fever with Thrombocytopenia Syndrome, Activated Partial Thromboplastin Time Prolongation, and Transient Antiphospholipid Antibodies

A prolonged activated partial thromboplastin time (APTT) is observed in patients with severe fever with thrombocytopenia syndrome (SFTS) and is one of the risk factors for severe disease. The mechanism underlying a prolonged APTT is largely unknown. The presence of antiphospholipid (aPL) antibodies in various viral infections has been documented but never reported in a patient with SFTS. We herein report the first SFTS patient with APTT prolongation and concurrent transiently positive aPL antibodies (lupus anticoagulants and anticardiolipin antibodies) with no coagulation factor deficiency.

[Parvovirus B19 infections in adults]

Acute Parvovirus B19 (PVB19) infection is responsible for erythema infectiosum in children and non-specific polyarthralgias in immunocompetent adults associated with skin lesions and rarer manifestations (hepatic, neurological, cardiac or nephrological). In immunocompromised patients, cytopenias are more frequent and in some cases, viremia persists and is responsible for PVB19 chronic infection. PVB19 is responsible for pure red cell aplasia during chronic hemolytic diseases. Acute PVB19 infection is a differential diagnosis of some autoimmune diseases and has been suspected to be a trigger for some autoimmune diseases because of its ability to promote the emergence of autoimmune markers. Mechanisms of molecular mimicry, induction of apoptosis and activation of enzymes have been demonstrated, explaining in part the production of autoantibodies during infection. However, the demonstration of a causal relationship in the triggering of autoimmune disease remains to be done. This review provides a synthesis of the PVB19 infection clinical data in adults with a particular focus on these links with autoimmunity.

Catastrophic antiphospholipid syndrome with Epstein-Barr virus-associated hemophagocytosis: A clinicopathological conference

Catastrophic antiphospholipid syndrome (CAPS) is a severe variant of antiphospholipid syndrome associated with multiorgan thrombosis in a short term. We present the case of a 14-year-old immunocompetent girl who developed renal, intestinal, and pulmonary infarction; thrombocytopenia; and hemolytic anemia within 1 week. She was diagnosed with thrombotic microangiopathy. Hence, plasma exchange and corticosteroid therapy were initiated, which improved thrombocytopenia. However, the patient's platelet count decreased. Her general condition gradually worsened with eventual death. An autopsy revealed multiple infarctions in the kidneys bilaterally, jejunum, ileum, and pulmonary parenchyma. Microthrombi were not detected. Massive hemophagocytosis was observed in the splenic pulp, lymph nodes, and bone marrow. Several Epstein-Barr viruses (EBVs)-encoded small ribonucleic acid (RNA)-positive lymphocytes were also found in the bone marrow. The presence of antibodies to both viral capsid antigen-immunoglobulin G and EBV nuclear antigen indicated past infection. Antiphospholipid antibody was positive after her death. The patient was finally diagnosed with CAPS and EBV-associated hemophagocytosis, possibly due to EBV reactivation. Establishing a clinical diagnosis of CAPS was relatively difficult because two different causes of thrombocytopenia, CAPS and hemophagocytosis, led to a difficulty in understanding this case's pathogenesis.

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.

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.

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.

Scrub Typhus and COVID-19 Coinfection Unmasking Antiphospholipid Antibody Syndrome

Scrub typhus is an acute febrile disease caused by Orientia tsutsugamushi with a clinical course varying from mild to fatal. Vascular thrombosis is rare in scrub typhus. There is an increased risk of thrombotic events in Coronavirus disease 19 (COVID-19). We report a young diabetic female who presented with pulmonary embolism, followed by deep venous thrombosis (DVT) and was found to have coinfection with scrub typhus and COVID-19 with underlying antiphospholipid antibody syndrome.

Multisystem Inflammatory Syndrome and Autoimmune Diseases Following COVID-19: Molecular Mechanisms and Therapeutic Opportunities

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2), has led to huge concern worldwide. Some SARS-CoV-2 infected patients may experience post–COVID-19 complications such as multisystem inflammatory syndrome, defined by symptoms including fever and elevated inflammatory markers (such as elevation of C reactive protein (CRP), erythrocyte sedimentation rate, fibrinogen, procalcitonin test, D-dimer, ferritin, lactate dehydrogenase or IL-6, presence of neutrophilia, lymphopenia, decreased albumin, and multiple organ dysfunction). Post–COVID-19 complications may also manifest as autoimmune diseases such as Guillain-Barré syndrome and systemic lupus erythematosus. Signaling disorders, increased inflammatory cytokines secretion, corticosteroid use to treat COVID-19 patients, or impaired immune responses are suggested causes of autoimmune diseases in these patients. In this review, we discuss the molecular and pathophysiological mechanisms and therapeutic opportunities for multisystem inflammatory syndrome and autoimmune diseases following SARS-CoV-2 infection with the aim to provide a clear view for health care providers and researchers.

Laboratory Diagnosis of Antiphospholipid Syndrome: Insights and Hindrances

Diagnosis of antiphospholipid syndrome (APS) requires the presence of a clinical criterion (thrombosis and/or pregnancy morbidity), combined with persistently circulating antiphospholipid antibodies (aPL). Currently, laboratory criteria aPL consist of lupus anticoagulant (LAC), anticardiolipin antibodies (aCL) IgG/IgM, and anti-β2 glycoprotein I antibodies (aβ2GPI) IgG/IgM. Diagnosis and risk stratification of APS are complex and efforts to standardize and optimize laboratory tests have been ongoing since the initial description of the syndrome. LAC detection is based on functional coagulation assays, while aCL and aβ2GPI are measured with immunological solid-phase assays. LAC assays are especially prone to interference by anticoagulation therapy, but strategies to circumvent this interference are promising. Alternative techniques such as thrombin generation for LAC detection and to estimate LAC pathogenicity have been suggested, but are not applicable yet in routine setting. For aCL and aβ2GPI, a lot of different assays and detection techniques such as enzyme-linked immunosorbent and chemiluminescent assays are available. Furthermore, a lack of universal calibrators or standards results in high variability between the different solid-phase assays. Other non-criteria aPL such as anti-domain I β2 glycoprotein I and antiphosphatidylserine/prothrombin antibodies have been suggested for risk stratification purposes in APS, while their added value to diagnostic criteria seems limited. In this review, we will describe laboratory assays for diagnostic and risk evaluation in APS, integrating applicable guidelines and classification criteria. Current insights and hindrances are addressed with respect to both laboratory and clinical implications.

Association between COVID-19 Diagnosis and Coronary Artery Thrombosis: A Narrative Review

Coronavirus disease 2019 is characterized by its severe respiratory effects. Data early on indicated an increased risk of mortality in patients with cardiovascular comorbidities. Early reports highlighted the multisystem inflammatory syndrome, cytokine storm, and thromboembolic events as part of the disease processes. The aim of this review is to assess the association between COVID-19 and its thrombotic complications, specifically related to the cardiovascular system. The role of neutrophil extracellular traps (NETs) is explored in the pathogenesis of the disease. The structure and anatomy of the virus are pivotal to its virulence in comparison to other α and β Coronaviridae (HCoV-229E, HCoV-OC43, HCoV-229E, HCoV-NL63, HCoV-OC43, and HCoV-HKU1). In particular, the host interaction and response may explain the variability of severity in patients. Angio tensin-converting enzyme 2 (ACE2) activation may be implicated in the cardiovascular and throm bogenic potential of the disease. The virus may also have direct effects on the endothelial lining affecting hemostasis and resulting in thrombosis through several mechanisms. Dipyridamole may have a therapeutic benefit in NET suppression. Therapeutic avenues should be concentrated on the different pathophysiological steps involving the virus and the host.

Cardiac and Cerebral Arterial Complications of Lemierre Syndrome: Results from a Systematic Review and Individual Patient Data Meta-analysis

Background  Lemierre syndrome is a potentially life-threatening disease, which affects otherwise healthy young adults and adolescents. It is characterized by acute neck vein thrombosis and septic embolism, usually complicating a bacterial infection. Data on the syndrome are sparse, particularly concerning arterial complications.

Methods  We evaluated the frequency and patterns of cerebral arterial and cardiac involvement (“arterial complications”) in an individual patient level cohort of 712 patients, representing all cases described over the past 20 years in the medical literature who fulfilled the criteria: (1) bacterial infection in the neck/head site and (2) objectively confirmed thrombotic complication or septic embolism. The study outcomes were defined as all-cause in-hospital deaths and the occurrence of clinical sequelae at discharge or in the postdischarge period.

Results  A total of 55 (7.7%) patients had an arterial complication. The most frequent arterial complications were carotid involvement (52.7%), stroke (38.2%), and pericardial complications (20%). Patients with an arterial involvement were more likely to be treated with a greater number of antibiotics (23 vs. 10%) and to receive anticoagulation. In addition, patients with arterial complications had a greater risk of all-cause death ( n  = 20/600, 3.3% vs. n  = 6/52, 12%; odds ratio [OR]: 3.8; 95% confidence interval [CI]: 1.5–9.9) and late clinical sequelae ( n  = 49/580, 9.0% vs. n  = 15/46, 35%; OR: 5.2; 95% CI: 2.65–10.37).

Conclusions  While Lemierre syndrome is known to be primarily characterized by venous thromboembolic events, our results suggest that local or distant arterial complications may occur in approximately one-tenth of patients and may be associated with a greater risk of long-term sequelae and death.

Antiphospholipid antibodies in patients with myocardial infarction with and without obstructive coronary arteries

BACKGROUND

Recent studies demonstrate that prothrombotic antiphospholipid antibodies (aPL) are overrepresented in patients with myocardial infarction (MI) due to coronary artery disease (MICAD). However, it is not known whether aPL differ between the two subsets of MI: MICAD and MI with nonobstructive coronary arteries (MINOCA).

OBJECTIVES

To determine whether aPL are associated with MINOCA or MICAD, or with hypercoagulability as assessed by activated protein C-protein C inhibitor (APC-PCI) complex.

METHODS

Well-characterized patients with MINOCA (n = 98), age- and gender-matched patients with MICAD (n = 99), and healthy controls (n = 100) were included in a cross-sectional case-control study. Autoantibodies (IgA/G/M) targeting cardiolipin and β₂ glycoprotein-I and specific nuclear antigens were analyzed by multiplexed bead technology. The concentration of APC-PCI was determined as a measure of hypercoagulability by an immunofluorometric sandwich assay.

RESULTS

Both prevalence and titers of aPL of the IgG isotype (anti-cardiolipin and/or anti-β₂ glycoprotein-I) were higher in patients with MINOCA and MICAD than in controls. aPL IgG positivity was twice as frequent among patients with MICAD than MINOCA (11% vs. 6%, nonsignificant). We observed no group differences regarding aPL IgA/M or antibodies targeting specific nuclear antigens. Levels of APC-PCI were elevated in aPL IgG-positive compared to aPL IgG-negative MICAD patients.

CONCLUSIONS

aPL IgG, but not IgA/M, are enriched particularly in patients with MICAD but also in patients with MINOCA, as compared to controls. Interestingly, signs of hypercoagulability-measured by increased levels of the APC-PCI complex-were present in aPL IgG-positive MICAD patients, indicating an association with functional disturbances of the coagulation system.

Endothelial cell-activating antibodies in COVID-19

OBJECTIVE

While endothelial dysfunction has been implicated in the widespread thrombo-inflammatory complications of coronavirus disease-19 (COVID-19), the upstream mediators of endotheliopathy remain for the most part cryptic. Our aim was to identify circulating factors contributing to endothelial cell activation and dysfunction in COVID-19.

METHODS

Human endothelial cells were cultured in the presence of serum or plasma from 244 patients hospitalized with COVID-19 and plasma from 100 patients with non-COVID sepsis. Cell adhesion molecules (E-selectin, VCAM-1, and ICAM-1) were quantified by in-cell ELISA.

RESULTS

Serum and plasma from patients with COVID-19 increased surface expression of cell adhesion molecules. Furthermore, levels of soluble ICAM-1 and E-selectin were elevated in patient serum and tracked with disease severity. The presence of circulating antiphospholipid antibodies was a strong marker of the ability of COVID-19 serum to activate endothelium. Depletion of total IgG from antiphospholipid antibody-positive serum markedly restrained upregulation of cell adhesion molecules. Conversely, supplementation of control serum with patient IgG was sufficient to trigger endothelial activation.

CONCLUSION

These data are the first to suggest that some patients with COVID-19 have potentially diverse antibodies that drive endotheliopathy, adding important context regarding thrombo-inflammatory effects of autoantibodies in severe COVID-19.

Characteristics of Patients With Antiphospholipid Antibody Positivity in the APS ACTION International Clinical Database and Repository

OBJECTIVE

To describe the baseline characteristics of patients with positivity for antiphospholipid antibodies (aPLs) who were enrolled in an international registry, the Antiphospholipid Syndrome (APS) Alliance for Clinical Trials and International Networking (APS ACTION) clinical database and repository, overall and by clinical and laboratory subtypes.

METHODS

The APS ACTION registry includes adults who persistently had positivity for aPLs. We evaluated baseline sociodemographic and aPL-related (APS classification criteria and "non-criteria") characteristics of patients overall and in subgroups (aPL-positive without APS, APS overall, thrombotic APS only, obstetric APS only, and both thrombotic APS/obstetric APS). We assessed baseline characteristics of patients tested for the presence of three aPLs (lupus anticoagulant [LAC] test, anticardiolipin antibody [aCL], and anti-β2 -glycoprotein I [anti-β2 GPI]) antibodies by aPL profiles (LAC only, single, double, and triple aPL positivity).

RESULTS

The 804 aPL-positive patients assessed in the present study had a mean age of 45 ± 13 years, were 74% female, and 68% White; additionally, 36% had other systemic autoimmune diseases. Of these 804 aPL-positive patients, 80% were classified as having APS (with 55% having thrombotic APS, 9% obstetric APS, and 15% thrombotic APS/obstetric APS). In the overall cohort, 71% had vascular thrombosis, 50% with a history of pregnancy had obstetric morbidity, and 56% had experienced at least one non-criteria manifestation. Among those with three aPLs tested (n = 660), 42% were triple aPL-positive. While single-, double-, and triple aPL-positive subgroups had similar frequencies of vascular, obstetric, and non-criteria events, these events were lowest in the single aPL subgroup, which consisted of aCLs or anti-β2 GPI only.

CONCLUSION

Our study demonstrates the heterogeneity of aPL-related clinical manifestations and laboratory profiles in a multicenter international cohort. Within single aPL positivity, LAC may be a major contributor to clinical events. Future prospective analyses, using standardized core laboratory aPL tests, will help clarify aPL risk profiles and improve risk stratification.

The presence of non-criteria manifestations negatively affects the prognosis of seronegative antiphospholipid syndrome patients: a multicenter study

Background

Seronegative antiphospholipid syndrome (SN-APS) is often defined as the presence of APS criteria manifestations, negative antiphospholipid antibodies (aPL), and coexistence of APS non-criteria manifestations. Nevertheless, the impact of these non-criteria features is still unclear. On a different note, the relevance of one single aPL positive determination in patients with APS manifestations is another domain with limited evidence. We aim to compare the course of SN-APS and single-positive aPL (SP-aPL) patients with that of individuals with APS manifestations without non-criteria features/aPL positivity (controls).

Methods

Retrospective analysis of patients with thrombosis/obstetric morbidity assessed in two European hospitals between 2005 and 2020. Patients were divided into SN-APS, SP-aPL, and control groups. Clinical characteristics, comorbidities, and therapies were compared.

Results

A total of 82 patients were included in the SN-APS group, 88 in the SP-aPL group, and 185 in the control group. In Cox regression model, SN-APS displayed more thrombosis recurrence than controls (HR 3.8, 95% CI 2.2–6.5, p < 0.001) even when adjusting for the presence of hereditary thrombophilia, systemic lupus erythematosus, or contraceptive hormonal treatment. In SP-aPL, the difference in thrombosis recurrence did not reach statistical significance (p = 0.078). Indefinite anticoagulation (p < 0.001 and p = 0.008, respectively) and vitamin K antagonist (VKA) use (p < 0.001 in both cases) were more common in SN-APS/SP-aPL.

Conclusion

SN-APS displayed more thrombosis recurrence, indefinite anticoagulation, and VKA use than controls without non-criteria manifestations. The presence of such features in patients with thrombosis and negative aPL may negatively impact their clinical course.

Managing Antiphospholipid Syndrome in Children and Adolescents: Current and Future Prospects

Pediatric antiphospholipid syndrome (APS) is a rare acquired multisystem autoimmune thromboinflammatory condition characterized by thrombotic and non-thrombotic clinical manifestations. APS in children and adolescents typically presents with large-vessel thrombosis, thrombotic microangiopathy, and, rarely, obstetric morbidity. Non-thrombotic clinical manifestations are frequently seen in pediatric APS and may be present even before the vascular thrombotic events occur. We review insights into the pathogenesis of APS and discuss potential targets for therapy. The identification of multiple immunologic abnormalities in patients with APS reveals molecular targets for current or future treatment. Management strategies, especially for APS in adolescents, require screening for additional prothrombotic risk factors and consideration of counseling regarding contraceptive strategies, lifestyle recommendations, treatment adherence, and mental health issues associated with this autoimmune thrombophilia. The main goal of therapy in pediatric APS is the prevention of thrombosis. The management of acute thrombosis events in children and adolescents is the same as for primary APS, which involves isolated occurrences, and secondary APS, which is seen in association with another autoimmune disease, e.g., systemic lupus erythematosus. A pediatric hematologist should be consulted so other differential thrombophilic conditions can be eliminated. Therapy includes unfractionated heparin or low-molecular-weight heparin followed by vitamin K antagonists. Treatment of catastrophic APS involves triple therapy (anticoagulation, intravenous corticosteroid pulse therapy, and plasma exchange) and may include intravenous immunoglobulin for children and adolescents with this condition. New drugs such as eculizumab and sirolimus seem to be promising drugs for APS.

Alice in Wonderland syndrome: a lesion mapping study

BACKGROUND AND PURPOSE

Alice in Wonderland syndrome (AIWS) is a rare neurological disorder, characterized by an erroneous perception of the body schema or surrounding space. It may be caused by a variety of neurological disorders, but to date, there is no agreement on which brain areas are affected. The aim of this study was to identify brain areas involved in AIWS.

METHODS

We conducted a literature search for AIWS cases following brain lesions. Patients were classified according to their symptoms as type A (somesthetic), type B (visual), or type C (somesthetic and visual). Using a lesion mapping approach, lesions were mapped onto a standard brain template and sites of overlap were identified.

RESULTS

Of 30 lesions, maximum spatial overlap was present in six cases. Local maxima were identified in the right occipital lobe, specifically in the extrastriate visual cortices and white matter tracts, including the ventral occipital fasciculus, optic tract, and inferior fronto-occipital fasciculus. Overlap was primarily due to type B patients (the most prevalent type, n = 22), who shared an occipital site of brain damage. Type A (n = 5) and C patients (n = 3) were rarer, with lesions disparately located in the right hemisphere (thalamus, insula, frontal lobe, hippocampal/parahippocampal cortex).

CONCLUSIONS

Lesion-associated AIWS in type B patients could be related to brain damage in visual pathways located preferentially, but not exclusively, in the right hemisphere. Conversely, the lesion location disparity in cases with somesthetic symptoms suggests underlying structural/functional disconnections requiring further evaluation.

Association of Parvovirus B19 with Rheumatic Diseases

Human parvovirus B19 infections are well reported to be associated with different autoimmune disorders. They can either mimic or trigger autoimmune diseases, such as systemic lupus erythematous (SLE), rheumatoid arthritis (RA), and vasculitis. A lack of awareness about this infection can result in delays in diagnosis and poor care. In this review, the basic biology and clinical aspects of the parvovirus, human immune response, and the pathogenesis in the rheumatic diseases are discussed.

Is steroid pulse therapy a suitable treatment for drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms? A systematic review of case reports in patients treated with corticosteroids in Japan

Drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms is a life-threatening severe cutaneous adverse reaction, characterized by multiple organ involvement and reactivation of herpes viruses. Although the mainstay of treatment is a high dosage of corticosteroids delivered by pulse therapy or conventional oral administration, it remains debatable which mode is better. To clarify this issue, we reviewed publications in Japan of 299 cases of drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms treated with corticosteroids, to evaluate safety concerns with regards to these two modes of treatment. As a result, we found that patients treated with pulse therapy more frequently suffered cytomegalovirus reactivation, persistency, and high mortality but less frequently experienced herpesvirus 6 reactivation or type 1 diabetes compared with those undergoing conventional treatment, suggesting that the administration mode may differentially modulate inflammatory responses toward distinct consequences. This is the first statistical analysis revealing that steroid pulse therapy frequently resulted in severe sequelae with high mortality. In terms of the risk of serious consequences, we consider that steroid pulse therapy should be eschewed for the treatment of drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms.

Assessment of antiphospholipid antibodies and calprotectin as biomarkers for discriminating mild from severe COVID-19

BACKGROUND

To explore the association of thrombo-inflammatory biomarkers with severity in coronavirus disease (COVID-19), we measured antiphospholipid antibodies (aPL) and calprotectin in sera of COVID-19 patients.

METHODS

Anticardiolipin antibodies (aCL) and anti-β2-glycoprotein I antibodies were measured using enzyme-linked immunosorbent assay (ELISA) and multiplex flow immunoassay (MFIA) in hospitalized COVID-19 patients (N = 105) and healthy controls (N = 38). Anti-phosphatidylserine/prothrombin antibodies, calprotectin, and C-reactive protein (CRP) levels were also measured. We assessed the potential correlation between calprotectin levels and various laboratory parameters that were measured during the hospitalization period. After stratifying COVID-19 patients into two groups by their oxygenation status or acute respiratory distress syndrome presentation, the discriminatory performance of each biomarker was evaluated.

RESULTS

A high proportion of COVID-19 patients (29.5%, 31/105) had low aCL IgM titers that were detectable by ELISA but mostly below the detection limit of MFIA. Calprotectin levels in severe groups of COVID-19 were significantly higher than those in non-severe groups, while CRP levels revealed no significant differences. Serum calprotectin levels showed strong to moderate degree of correlation with other routinely used parameters including peak levels of CRP, ferritin, procalcitonin, BUN, and neutrophil-to-lymphocyte ratio, but a negative correlation with minimal lymphocyte count and CD4⁺ T cells. The discriminatory performance was highest for calprotectin in discriminating severe groups of COVID-19.

CONCLUSIONS

Serum calprotectin levels were significantly elevated in severe COVID-19 cases. The prevalence of clinically significant aPL did not differ. The link between calprotectin and inflammatory pathway in COVID-19 may help improve the management and outcomes of COVID-19 patients.

Endothelial cell-activating antibodies in COVID-19

Objectives

Patients with coronavirus disease 19 ( COVID-19 ) are at high risk for fibrin-based occlusion of vascular beds of all sizes. Considering endothelial cell activation has regularly been described as part of the COVID-19 thrombo-inflammatory storm, we aimed to find upstream mediators of this activation.

Methods

Cultured endothelial cells were exposed to sera or plasma from 244 patients hospitalized with COVID-19 or plasma from 100 patients in the intensive care unit with sepsis. Cell adhesion molecules E-selectin, VCAM-1, and ICAM-1 were detected by in-cell ELISA. Soluble E-selectin was measured in serum.

Results

As compared with healthy controls, sera and plasma from patients with COVID-19, and to a lesser extent plasma from patients with sepsis, increased expression of E-selectin, VCAM-1, and ICAM-1 on cultured endothelial cells. We found modest correlations between serum neutrophil extracellular trap (NET) remnants and upregulation of cell adhesion molecules on endothelial cells. A stronger marker of the ability of COVID-19 serum to activate endothelial cells was the presence of circulating antiphospholipid antibodies, specifically anticardiolipin IgG and IgM and anti-phosphatidlyserine/prothrombin (anti-PS/PT) IgG and IgM. Depletion of total IgG from anticardiolipin-positive and anti-PS/PT-positive samples markedly restrained upregulation of E-selectin, VCAM-1, and ICAM-1. At the same time, supplementation of control serum with patient IgG was sufficient to trigger endothelial cell activation.

Conclusions

These data are the first to suggest that some patients with COVID-19 have potentially diverse antibodies that drive endothelial cell activation in COVID-19. The data also add important context regarding thrombo-inflammatory effects of autoantibodies in severe COVID-19.

KEY MESSAGES

What is already known about this subject?: Patients with COVID-19 are at high risk for fibrin-based occlusion of vascular beds of all sizes.Endothelial cell activation has regularly been described as part of the COVID-19 thrombo-inflammatory storm.What does this study add?: The presence of circulating antiphospholipid antibodies may be a predictor of the ability of a patient’s total antibody profile to activate endothelial cells.Purified COVID-19 IgG with high levels of anticardiolipin and anti-PS/PT activity trigger a pro-adhesive phenotype in endothelial cells.How might this impact on clinical practice or future developments?: Patients might be screened for antiphospholipid antibodies to evaluate their risk of having an antibody profile likely to activate endothelial cells.Patients with high antiphospholipid antibody titers might benefit from treatments used in traditional cases of severe APS such as therapeutic anticoagulation, corticosteroids, and plasmapheresis.

Is Lupus Anticoagulant a Significant Feature of COVID-19? A Critical Appraisal of the Literature

The term "lupus anticoagulant (LA)" identifies a form of antiphospholipid antibodies (aPLs) causing prolongation of clotting tests in a phospholipid concentration-dependent manner. LA is one of the laboratory criteria identified in patients with antiphospholipid (antibody) syndrome (APS). The presence of LA in patients with APS represents a significant risk factor for both thrombosis and pregnancy morbidity. There have been several reports of similarities between some of the pathophysiological features of COVID-19 and APS, in particular the most severe form, catastrophic APS. There have also been many reports identifying various aPLs, including LA, in COVID-19 patients. Accordingly, a very pertinent question arises: "Is LA a feature of COVID-19 pathology?" In this review, we critically appraise the literature to help answer this question. We conclude that LA positivity is a feature of COVID-19, at least in some patients, and potentially those who are the sickest or have the most severe infection. However, many publications have failed to appropriately consider the many confounders to LA identification, being assessed using clot-based assays such as the dilute Russell viper venom time, the activated partial thromboplastin time (aPTT), and the silica clotting time. First, most patients hospitalized with COVID-19 are placed on anticoagulant therapy, and those with prior histories of thrombosis would possibly present to hospital already on anticoagulant therapy. All anticoagulants, including vitamin K antagonists, heparin (both unfractionated heparin and low-molecular-weight heparin), and direct oral anticoagulants affect these clot-based assays. Second, C-reactive protein (CRP) is highly elevated in COVID-19 patients, and also associated with severity. CRP can also lead to false-positive LA, particularly with the aPTT assay. Third, persistence of aPL positivity (including LA) is required to identify APS. Fourth, those at greatest risk of thrombosis due to aPL are those with highest titers or multiple positivity. Most publications either did not identify anticoagulation and/or CRP in their COVID-19 cohorts or did not seem to account for these as possible confounders for LA detection. Most publications did not assess for aPL persistence, and where persistence was checked, LA appeared to represent transient aPL. Finally, high titer aPL or multiple aPL positivity were in the minority of COVID-19 presentations. Thus, at least some of the reported LAs associated with COVID-19 are likely to be false positives, and the relationship between the detected aPL/LA and COVID-19-associated coagulopathy remains to be resolved using larger and better studies.

COVID-19 and Antiphospholipid Antibodies: Time for a Reality Check?

Antiphospholipid antibodies (aPL) comprise a panel of autoantibodies that reflect a potential prothrombotic risk in several autoimmune conditions, most notably antiphospholipid (antibody) syndrome (APS). aPL can be divided into those that form part of the laboratory criteria for APS, namely, lupus anticoagulant (LA), as well as anticardiolipin antibodies (aCL) and anti-β2-glycoprotein I antibodies (aβ2GPI) of the immunoglobulin G and M classes, and those that form a group considered as "noncriteria antibodies." The noncriteria antibodies include, for example, antiphosphatidylserine antibodies (aPS), antiprothrombin antibodies (aPT), and antiphosphatidylserine/prothrombin complex antibodies (aPS/PT). COVID-19 (coronavirus disease 2019) represents a prothrombotic disorder, and there have been several reports of various aPL being present in COVID-19 patients. There have also been similarities drawn between some of the pathophysiological features of COVID-19 and APS, in particular, the most severe form, catastrophic APS (CAPS). In this review, we critically appraise the literature on aPL and COVID-19. This is a companion piece to a separate review focused on LA. In the current review, we primarily concentrate on the so-called solid phase identifiable aPL, such as aCL and aβ2GPI, but also reflect on noncriteria aPL. We conclude that aPL positivity may be a feature of COVID-19, at least in some patients, but in general, identified "solid-phase" aPL are of low titer and not able to be well-linked to the thrombotic aspects of COVID-19. Also, most publications did not assess for aPL persistence, and where persistence was checked, the findings appeared to represent transient aPL. Importantly, high-titer aPL or multiple aPL positivity (including double, triple) were in the minority of COVID-19 presentations, and thus discount any widespread presence of APS, including the most severe form CAPS, in COVID-19 patients.

COVID-19 in patients with systemic lupus erythematosus: lessons learned from the inflammatory disease

As the world navigates the coronavirus disease 2019 (COVID-19) pandemic, there is a growing need to assess its impact in patients with autoimmune rheumatic diseases, such as systemic lupus erythematosus (SLE). Patients with SLE are a unique population when considering the risk of contracting COVID-19 and infection outcomes. The use of systemic glucocorticoids and immunosuppressants, and underlying organ damage from SLE are potential susceptibility factors. Most patients with SLE have evidence of high type I interferon activity, which may theoretically act as an antiviral line of defense or contribute to the development of a deleterious hyperinflammatory response in COVID-19. Other immunopathogenic mechanisms of SLE may overlap with those described in COVID-19, thus, studies in SLE could provide some insight into immune responses occurring in severe cases of the viral infection. We reviewed the literature to date on COVID-19 in patients with SLE and provide an in-depth review of current research in the area, including immune pathway activation, epidemiology, clinical features, outcomes, and the psychosocial impact of the pandemic in those with autoimmune disease.

16th International congress on antiphospholipid antibodies task force report on clinical manifestations of antiphospholipid syndrome

The objectives of the 16th International Congress on Antiphospholipid Antibodies (aPL) Task Force on Clinical Manifestations of Antiphospholipid Syndrome (APS) were to critically analyze: a) the definition of "APS"; b) the current knowledge on non-traditional manifestations associated with aPL; and c) the risk stratification strategies in aPL-positive patients. The quality of evidence was assessed by the GRADE system. The task force concluded that: a) APS does not have a uniform definition given the heterogeneity of the clinical presentations and different aPL profiles; b) current literature supports the role for aPL testing in cases of thrombocytopenia and recurrent cardiac events but are limited by vast heterogeneity, providing an overall low-to-very low level of evidence; and c) risk stratification strategies in aPL-positive patients, such as aPL-Score and Global APS Score, can be useful in clinical practice. International multicenter studies are still highly needed to improve the quality of available evidence and consequently the strength of future recommendations.

Management of patients with antiphospholipid antibodies: what to do in laboratory scenarios that do not fit the guidelines

Introduction: Some patients with positive antiphospholipid antibodies (aPL) have not been included in randomized clinical trials or observational registries and, therefore, information on their risk of obstetric or thrombotic recurrence and optimal treatment is scarce.Areas covered: In the present review, the existing evidence regarding the management of two laboratory scenarios not covered by the guidelines is presented: (1) patients with antiphospholipid syndrome (APS) clinical manifestations and aPL positivity not fulfilling APS laboratory criteria, and (2) the possibility of discontinuing anticoagulation in APS patients whose aPL become persistently negative.Expert opinion: Growing evidence suggests a role for low titers and 'non-criteria' aPL, especially in obstetric APS. Treatment is not formally recommended but might be considered according to the individual's risk profile. Regarding the question of whether or not to discontinue anticoagulants after the 'spontaneous' disappearance of aPL, there is no definite answer. Retrospective studies seem to suggest that withdrawal of anticoagulation could be safe in certain patients with APS, especially in those with a first provoked venous thrombosis and whose aPL became persistently negative during follow-up. Still, before the withdrawal can be recommended in routine clinical practice, multicenter and prospective studies are required to validate this hypothesis.

Autoantibodies Among HIV-1 Infected Individuals and the Effect of Anti-Retroviral Therapy (ART) on It

BACKGROUND

Antiretroviral therapy (ART) has led to a decline in autoimmune diseases but lacks studies on its effect on autoantibodies.

METHODS

It is a cross-sectional study with archived samples from 100 paired HIV-1 infected ART naïve and experienced individuals and 100 prospectively collected matched blood-donor controls. Antinuclear antibody, IgG anticardiolipin antibody, IgM and IgG β2 glycoprotein-1 antibodies, and total IgG levels were detected. Results are expressed as mean with standard deviation (SD), median, percentage positivity, and a p<0.05 is considered significant. The study was approved by the Institutional Review Board.

RESULTS

The median viral load of the treatment naïve samples was 4.34 Log copies/mL, while all were virally suppressed post ART with a median duration of treatment for 12 months (range: 3-36 months). The percentage of antinuclear antibody positivity was 5% among ART naïve and controls, with a decrease of 2% post ART (p= 0.441). The positivity for anti-cardiolipin antibody was 15% among ART naïve while none of the ART experienced or controls were positive (p<0.05). IgM β2 glycoprotein-1 were 4%, 1% and 3% among ART naïve, treated and controls, respectively (p<0.05). IgG β2 glycoprotein-1 was 2% among ART naïve while none of the treated and controls were positive (p<0.05). The mean total IgG level among ART naïve, experienced, and controls were 21.82 (SD 6.67), 16.91 (SD 3.38), 13.70 (SD 2.24) grams/Litre, respectively (p<0.05).

CONCLUSION

ART has a significant effect on IgG anti-cardiolipin antibody and total IgG but only a marginal effect on ANA, IgM, and IgG β2 glycoprotein-1 antibodies.

Prevalence and clinical significance of antiphospholipid antibodies in patients with coronavirus disease 2019 admitted to intensive care units: a prospective observational study

Coronavirus disease 2019 (COVID-19) increases the risk of coagulopathy. Although the presence of antiphospholipid antibodies (aPLs) has been proposed as a possible mechanism of COVID-19-induced coagulopathy, its clinical significance remains uncertain. Therefore, this study aimed to evaluate the prevalence and clinical significance of aPLs among critically ill patients with COVID-19. This prospective observational study included 60 patients with COVID-19 admitted to intensive care units (ICU). The study outcomes included prevalence of aPLs, and a primary composite outcome of all-cause mortality and arterial or venous thrombosis between antiphospholipid-positive and antiphospholipid-negative patients during their ICU stay. Multiple logistic regression was used to assess the influence of aPLs on the primary composite outcome of mortality and thrombosis. A total of 60 critically ill patients were enrolled. Among them, 57 (95%) were men, with a mean age of 52.8 ± 12.2 years, and the majority were from Asia (68%). Twenty-two patients (37%) were found be antiphospholipid-positive; 21 of them were positive for lupus anticoagulant, whereas one patient was positive for anti-β2-glycoprotein IgG/IgM. The composite outcome of mortality and thrombosis during their ICU stay did not differ between antiphospholipid-positive and antiphospholipid-negative patients (4 [18%] vs. 6 [16%], adjusted odds ratio 0.98, 95% confidence interval 0.1–6.7; p value = 0.986). The presence of aPLs does not seem to affect the outcomes of critically ill patients with COVID-19 in terms of all-cause mortality and thrombosis. Therefore, clinicians may not screen critically ill patients with COVID-19 for aPLs unless deemed clinically appropriate.