Four clinical and biological phenotypes in antiphospholipid syndrome: a cluster analysis of 174 patients with antinuclear antibody tests

Introduction

Antiphospholipid syndrome (APS) is an autoimmune thrombotic disease with various systemic presentations. This study aimed to identify homogeneous groups of patients based on a non-supervised hierarchical cluster analysis and assess the rate of relapse associated with antinuclear antibodies (ANA).

Methods

This retrospective observational study enrolled patients, over a 90-month period, who had APS as defined by the 2006 Sydney classification criteria, and for whom ANA workup was performed. Agglomerative unsupervised hierarchical clustering was conducted to classify patients into subgroups using 24 variables reflecting a range of clinical and biological baseline features associated with APS.

Results

Hundred and seventy-four patients were included and were categorized into four phenotypes. Cluster 1 (n=73) associated mostly middle-aged men with risk factors for cardiovascular disease. Obstetrical APS with low-risk thrombosis made up cluster 2 (n=25). Patients with venous thromboembolism (VTE), microvascular findings and double/triple positive APL antibodies (50%) were represented in cluster 3 (n=33). Whereas cluster 4 (n=43) characterized a predominantly female subpopulation with positive ANA and systemic lupus (n=23) that exhibited a high thrombotic risk and more frequent relapses (n=38) (p<0.001).

Conclusions

This study identified four homogenous groups of patients with APS listed as: i) cardiovascular and arterial risk, ii) obstetrical, iii) VTE and microvascular, and iv) ANA-positive APS. We found that ANA-positivity was associated with higher rates of relapse. Applying ANA status to classification criteria could constitute a novel approach to tailoring management for APS, based on phenotypic patterns and risk assessment.

Stroke and Risk Factors in Antiphospholipid Syndrome

Stroke is considered one of the most common and life-threatening manifestations of antiphospholipid syndrome (APS), which leads to high mortality and permanent disability. This study investigated the prevalence and the potential risk factors of stroke in APS. We enrolled 361 APS patients retrospectively from 2009 to 2022 at Peking University People's Hospital. Stroke was found in 25.8% (93/361) of the participants. The multivariate logistic regression showed that hypertension, diabetes, livedo reticularis, and other central nervous system involvements were significant related factors for stroke. The use of hydroxychloroquine appeared to relate to a lower incidence of stroke. During a median follow-up of 3.0 years, 11.8% (11/93) of the individuals with a previous stroke developed stroke recurrence, and thrombocytopenia seemed to be a predictor of stroke recurrence.

Trends of Coagulation Parameters in Human Immunodeficiency Virus Patients

Background and Objectives: HIV disease is recognized to cause inconsistencies in coagulation via various pathways during infection. Some studies have indicated that HIV-infected patients are prone to developing thrombocytopenia, thrombosis, or autoantibodies that may cause difficulties in diagnosis. This study is intended to measure the trend of coagulation parameters in Sudanese patients with HIV. Materials and Methods: A cross-sectional study was carried out in patients with HIV admitted to the Sudan National AIDS Program (SNAP) from January 2018 to December 2019. Prothrombin time (PT), partial thromboplastin time (PTT), thrombin time (TT), D-dimer (DD), hemoglobin (HB), total lymphocyte count (TLC), platelet count (PLT), and a disintegrin and metalloproteinase with thrombospondin type 1 motif, member 13 (ADAMTS13), were evaluated among HIV Sudanese patients. Results: Out of the 44 HIV patients included, 6 (13.6%) were found to have thrombotic thrombocytopenic purpura-like events and 12 (27.2%) had antiphospholipid antibodies, of whom 8 (66.6%) showed anticardiolipin antibody (1gG (75%) and IgM (25%)) and 4 showed lupus anticoagulants. The HB, TLC, and PLT values were found to be significantly lower in HIV patients than in control (p = 0.000, 0.000, and 0.050, respectively). The PT and ADAMTS13 values showed no significant difference between HIV patients and control (p = 0.613 and 0.266, respectively). The PTT, TT, and DD values were found to be augmented in HIV patients versus the control (p = 0.000). Conclusions: Thrombotic thrombocytopenic purpura-like events among HIV Sudanese patients were explored. In addition, antiphospholipid antibodies were strikingly seen in these patients. Additional research is anticipated to confirm these diagnoses.

vitamin K antagonists in patients with antiphospholipid syndrome: a systematic review and meta-analysis

Optimal treatment regimen for patients with antiphospholipid syndrome (APS) remain unclear. Therefore, the authors sought to compare the outcomes of vitamin K antagonists (VKAs) vs. direct oral anticoagulants (DOACs) in patients with APS.

METHODS

MEDLINE, Embase, and Cochrane Central databases were searched for randomized controlled trials comparing efficacy and safety of VKAs and DOACs inhibitors in patients with APS. Recurrent thrombosis, all-cause mortality, stroke, adverse reactions, and bleeding were among outcomes of interest. Mantel-Haenszel weighted random-effects model was used to calculate relative risks (RRs) with 95% CIs.

RESULTS

The analysis included 625 patients from four randomized controlled trials and one post hoc analysis. Meta-analysis showed statistically non-significant difference between DOACs inhibitors and VKAs in the recurrent thrombosis risk (arterial or venous) [RR 2.77 (95%, CI 0.79, 9.65); P=0.11, I2=50%]. Consistent results were revealed among patients with the previous history of arterial thrombosis [RR 2.76 (95% CI 0.93, 8.16); P=0.75, I2=0%], venous thrombosis [RR 1.71 (95% CI 0.60, 4.84); P=0.31, I2=15%] and patients who were triple antiphospholipid positive [RR 4.12 (95% CI 0.46, 37.10); P=0.21, I2=58%]. DOACs inhibitors were significantly associated with increased risk of stroke [RR 8.51 (95% CI 2.35, 3.82); P=0.47, I2=0%].

CONCLUSION

DOACs exhibited increased risk of stroke among patients with APS. In addition, although not significant, the higher RRs among patients on DOACs may indicate higher risk of thrombotic events associated with DOACs.

Lupus anticoagulant hypoprothrombinemia syndrome: A case report

Lupus anticoagulant hypoprothrombinemia syndrome (LAHPS) is a rare entity associated with an increased risk of hemorrhage. Corticosteroids have been used in its treatment with favorable results. We present the case of a 54-year-old female patient with a personal history of Lupus diagnosed with LAHPS following an episode of cerebellar hemorrhage.

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.

Anti-phosphatidylserine prothrombin antibodies as a predictor of the lupus anticoagulant in an all-comer population

BACKGROUND

Anti-phosphatidylserine prothrombin antibodies (aPSPT) are reported to be highly associated with the lupus anticoagulant (LAC) in established antiphospholipid syndrome (APS) and systemic lupus erythematosus (SLE) cohorts. Further, aPSPT has been suggested to be a useful surrogate LAC marker. However, validation studies replicating this relationship in an all-comer study population in the diagnostic clinical setting are lacking.

OBJECTIVES

To determine the sensitivity and specificity of aPSPT to the LAC in an all-comer population undergoing evaluation for suspected APS.

METHODS

An assembled cross-sectional cohort from June 2017 to December 2018 undergoing APS evaluations across all medical specialties were reviewed for LAC, aPSPT, anti-cardiolipin (aCL), and anti-β2 glycoprotein-1 (β2GP1). Sensitivities, specificities, and negative and positive predictive values were calculated.

RESULTS AND CONCLUSIONS

A cohort of 166 eligible patients was identified. Seventy-one percent were female, 89% White, 15% with SLE, and 21% with APS. The aPSPT was found to be the most specific to the LAC. Specificity of IgG aPSPT was 100% (96%-100%) and IgM aPSPT was 97% (91%-100%) to the LAC. Corresponding positive predictive value for IgG aPSPT was 100% (89%-100%) and IgM aPSPT was 95% (84%-99%). In contrast, the sensitivities of aPSPT to the LAC were less robust, only in the 40%-50% range. The findings validate previously reported findings and lends extension to an all-comer population. These findings corroborate aPSPT as a potentially useful clinical marker of the LAC.

Cardiac Magnetic Resonance in Rheumatology to Detect Cardiac Involvement Since Early and Pre-clinical Stages of the Autoimmune Diseases: A Narrative Review

Autoimmune diseases (ADs) encompass multisystem disorders, and cardiovascular involvement is a well-known feature of autoimmune and inflammatory rheumatic conditions. Unfortunately, subclinical and early cardiovascular involvement remains clinically silent and often undetected, despite its well-documented impact on patient management and prognostication with an even more significant effect on severe and future MACE events as the disease progresses. Cardiac magnetic resonance imaging (MRI), today, commands a unique position of supremacy versus its competition in cardiac assessment and is the gold standard for the non-invasive evaluation of cardiac function, structure, morphology, tissue characterization, and flow with the capability of evaluating biventricular function; myocardium for edema, ischemia, fibrosis, infarction; valves for thickening, large masses; pericardial inflammation, pericardial effusions, and tamponade; cardiac cavities for thrombosis; conduction related abnormalities and features of microvascular and large vessel involvement. As precise and early detection of cardiovascular involvement plays a critical role in improving the outcome of rheumatic and autoimmune conditions, our review aims to highlight the evolving role of CMR in systemic lupus erythematosus (SLE), antiphospholipid syndrome (APS), rheumatoid arthritis (RA), systemic sclerosis (SSc), limited sclerosis (LSc), adult-onset Still's disease (AOSD), polymyositis (PM), dermatomyositis (DM), eosinophilic granulomatosis with polyangiitis (EGPA) (formerly Churg-Strauss syndrome), and DRESS syndrome (DS). It draws attention to the need for concerted, systematic global interdisciplinary research to improve future outcomes in autoimmune-related rheumatic conditions with multiorgan, multisystem, and cardiovascular involvement.

Rapidly progressive ischemic strokes and transient antiphospholipid syndrome during a mild SARS-CoV-2 infection

SARS-CoV-2 infection is associated with an increased risk of thrombotic events, especially during severe forms of disease. Here we describe the clinical history of a patient with a mild form of Covid-19 infection presenting with multiple cerebral ischemic lesions that evolved in an atypical way.

Immunological parameters of recurrent miscarriages among women in Thi-Qar province

Recurrent miscarriage (RM) is defined as the loss of pregnancy three or more consecutive times in the first and second trimester, which in some cases occurs due to immune abnormalities. This study aimed to assess some immunological parameters in women with recurrent miscarriages, including the level of antiphospholipid antibody (APA), anticardiolipin (ACA), antinuclear antibody (ANA), complement C3 and C4, and interleukine-3 (IL-3). We included 100 patients together with 100 healthy women as a control. ELIZA was used to measure some types of autoantibodies. APA and ACA significantly increased (P≤0.05) in patients compared to control. In addition, 29% of the patients were positive for antinuclear antibodies (ANA), while the control subjects had negative results for these autoantibodies. Regarding the complement, the serum levels of C3 and C4 were significantly elevated in the serum level of patients when compared to the control group, but in treated patients (heparin and low-dose aspirin), the levels of the complement (C3 and C4) showed a significant decrease in patients compared to total controls. Cytokine level (IL-3) significantly decreased in untreated patients 302.78 pg/ml compared to treated patients (741.57 pg/ml). Antiphospholipid antibodies are more prevalent among women with recurrent miscarriages and are also believed to be the result of abnormal autoimmune activation.

The clinical significance of antiphospholipid antibodies in COVID-19 infection

INTRODUCTION

One of the factors that may aggravate the clinical presentation in COVID-19 is the increased level of antiphospholipid antibodies (aPLs) and thrombotic events that can be seen with the disease. In our retrospective study, we aimed to evaluate the effect of aPLs on the clinical findings in patients with a diagnosis of COVID-19.

METHODOLOGY

Seventy-three patients diagnosed with COVID-19 and examined for aPLs were included in the study. Patients were divided into two groups according to the test results of aPLs. Clinical and laboratory parameters were compared in both groups to reveal whether there was any difference between the groups.

RESULTS

There were 15 patients with a positive aPLs test. Dyspnea, nausea, vomiting, myalgia, and abdominal pain were significantly higher in the aPLs positive group than those with negative aPLs. The duration of hospital stays and the need for oxygen therapy of the patients in the aPLs positive group were significantly higher than the aPLs negative group. However, no difference was found between the two groups in terms of mechanical ventilation need, intensive care admission rate, thrombosis and mortality. In terms of laboratory findings, those with positive aPLs have higher median C-reactive protein (CRP) and ferritin values than those with negative aPLs.

CONCLUSIONS

In our study group, we could not find a relationship between aPLs positivity and critical complications. According to our hypothesis, it may not be necessary to routinely examine aPLs in patients with a diagnosis of COVID-19 to determine the risk of thromboembolic complications.

Production of anti-PF4 antibodies in antiphospholipid antibody-positive patients is not affected by COVID-19 vaccination

BACKGROUND

Antibodies against cationic platelet chemokine, platelet factor 4 (PF4/CXCL4), have been described in heparin-induced thrombocytopenia (HIT), but also in patients positive for antiphospholipid antibodies (aPL) even in the absence of heparin treatment and HIT-related clinical manifestations. Anti-PF4 antibodies have been recently described also in subjects who developed thrombosis with thrombocytopenia syndrome (TTS) in association with adenoviral vector-based, but not with mRNA-based, COVID-19 vaccines.

OBJECTIVE

To investigate whether COVID-19 vaccination affects the production of anti-PF4 antibodies in aPL-positive patients and in control groups.

METHODS

Anti-PF4 immunoglobulins were detected in patients' and controls' serum samples by ELISA and their ability to activate normal platelets was assessed by the platelet aggregation test.

RESULTS

Anti-PF4 were found in 9 of 126 aPL-positive patients, 4 of 50 patients with COVID-19, 9 of 49 with other infections, and 1 of 50 aPL-negative patients with systemic lupus erythematosus. Clinical manifestations of TTS were not observed in any aPL patient positive for anti-PF4, whose serum failed to cause platelet aggregation. The administration of COVID-19 vaccines did not affect the production of anti-PF4 immunoglobulins or their ability to cause platelet aggregation in 44 aPL-positive patients tested before and after vaccination.

CONCLUSIONS

Heparin treatment-independent anti-PF4 antibodies can be found in aPL-positive patients and asymptomatic carriers, but their presence, titre as well as in vitro effect on platelet activation are not affected by COVID-19 vaccination.

Cardiovascular risk management in antiphospholipid syndrome: trends over time and comparison with rheumatoid arthritis and diabetes mellitus

Objective

Antiphospholipid syndrome (APS) is characterised by increased cardiovascular morbidity and mortality, related to thrombo-inflammatory and atherogenic mechanisms. We examined the achievement of traditional cardiovascular risk factor (CVRF) therapeutic goals in APS versus other high cardiovascular risk disorders such as rheumatoid arthritis (RA) and diabetes mellitus (DM), and trends over time.

Methods

122 patients with APS (74 primary APS, female 68%, mean age 44.5±11.3) were classified according to their first visit (2011–2015 and 2016–2020 APS subgroups, 61 patients in each subgroup) and matched 1:1 for age/sex with patients with RA and DM. Cardiovascular risk was estimated by the Systemic Coronary Risk Evaluation, and the CVRF therapeutic targets were defined according to the European Society of Cardiology (ESC) guidelines. Individual and multiple CVRF control was compared between APS subgroups, and in APS versus RA and DM.

Results

We found a comparable or higher prevalence of CVRFs between APS and age-matched/sex-matched patients with RA and DM but low CVRF target attainment in APS according to the ESC guidelines. Despite improving trends between 2011–2015 and 2016–2020, CVRF control in high/very high-risk patients with APS was 12%, 18%, 24% and 35% for low-density lipoprotein, waist circumference, exercise and body mass index, respectively, and 59%–65% for triglycerides, high-density lipoprotein (HDL) and blood pressure, in 2016–2020 subgroup. CVRF control was worse in APS versus RA for smoking (p=0.014), HDL (p<0.001), waist circumference (p=0.042) and five CVRFs (p=0.030), and versus DM for exercise (p=0.077). Similar results were found in the sensitivity analysis.

Conclusions

Comparable prevalence of modifiable CVRFs to RA and DM but suboptimal CVRF target achievement was observed in APS, especially in high/very high-risk patients, highlighting the need for CVRF management strategies.

Immune thrombocytopenia with clinical significance in systemic lupus erythematosus: a retrospective cohort study of 90 patients

OBJECTIVES

To describe the characteristics, treatment, and outcome of patients with immune thrombocytopenia with clinical significance (ITPCS) associated with systemic lupus erythematosus (SLE).

METHODS

This retrospective multicentre study included SLE patients who experienced ≥1 ITPCS (defined as ITP with attributable bleeding disorders and/or a platelet count <30 x109/L). Other causes of secondary thrombocytopenia were excluded. Major bleeding event (MBG) was defined as Khellaf score>8 and/or WHO score>2.

RESULTS

A total of 90 patients were included, the median (range) follow-up duration was 80 (6-446) months. ITP was diagnosed before SLE in 25 patients. They presented high rate of autoimmune haemolytic anaemia (15%), antiphospholipid antibody (62%), and antiphospholipid syndrome (19%). The 25 (28%) patients who experienced MBG had significantly more bleedings at ITP diagnosis and higher bleeding scores, and serositis and thrombosis during follow-up. They required significantly more treatment lines, transfusions, and hospitalizations. The 11 (12%) patients who experienced no bleeding event presented a significantly more restricted SLE phenotype (cutaneous and/or articular). Patients received a mean (range) of 4.2 (1-11) treatment lines. Corticosteroids and hydroxychloroquine allowed ITPCS overall response in one third of patients. The median relapse-free survival of rituximab (n = 34), azathioprine (n = 19), mycophenolate mofetil (n = 8), thrombopoietin-receptor agonists (n = 16), and splenectomy (n = 19) were 53, 31.5, 61, 24.5, and 78 months, respectively. Four patients experienced thrombotic events after splenectomy and one occurred under thrombopoietin-receptor agonist treatment.

CONCLUSION

SLE-ITCS patients displayed a high rate of haematological abnormalities and MBG patients exhibited higher morbidity. Management of thrombocytopenia was highly heterogeneous and many options seem viable.

Loss of antiphospholipid antibody positivity post-thrombosis in SLE

Background/Purpose

Loss of positivity of antiphospholipid antibodies has been observed in clinical practice post-thrombosis in patients with SLE with secondary antiphospholipid syndrome (APS). Our study defined the frequency of this loss and the duration before positivity recurred.

Methods

In this prospective study, patients with SLE having at least two positive antiphospholipid markers prior to thrombosis and at least 1 year of follow-up after thrombosis were included. Antiphospholipid markers included lupus anticoagulant (dilute Russell viper venom test >45 s followed by mixing and confirmatory tests) and/or anticardiolipin titre (aCL IgG ≥20, aCL IgM ≥20 and/or aCL IgA ≥20). The percentage of visits with positive antiphospholipid markers after thrombosis was calculated. For patients with a negative antiphospholipid marker any time after thrombosis, survival estimates were performed to calculate the time to return of antiphospholipid positivity.

Results

In APS due to SLE, complete loss of antiphospholipid positivity post-thrombosis was up to 41% for aCL IgG, 51% for IgM and 50% for IgA, but only 20% for those with lupus anticoagulant. Of those who at some point lost aCL IgG or became negative for lupus anticoagulant, the majority (60% and 76%, respectively) reacquired the antibody within 5 years. In contrast, of those who lost aCL IgM or IgA, fewer reacquired it within 5 years (37% and 17%, respectively).

Conclusion

Intermittent positivity of antiphospholipid antibodies is present in APS due to SLE. These fluctuations make it difficult to decide on length of anticoagulation. Lupus anticoagulant is more likely to persist post-thrombosis.

Evaluation of different ways to identify persistent positivity of lupus anticoagulant in systemic lupus erythematosus

Objective

Persistent positivity for lupus anticoagulant has been associated with an increased risk of thrombosis among patients with SLE. Persistent positivity is often defined as having two positive assessments separated by more than 90 days. Our objective was to determine whether frequent repeated lupus anticoagulant testing would identify more patients with persistent positivity, and whether the additional patients identified were still at increased risk of thrombosis.

Methods

Using a large longitudinal cohort with frequent lupus anticoagulant testing, we compared three different hypothetical clinical strategies for identifying persistent positivity: (1) assessment of lupus anticoagulant twice more than 90 days apart; (2) assessment of lupus anticoagulant annually, with repeat testing if an annual assessment was positive; and (3) assessment of lupus anticoagulant 16 times (approximately quarterly for 4 years). The prevalence of persistent positivity was compared between the approaches and by demographic subgroups. Subgroups based on these definitions were compared with respect to the risk of thrombosis in subsequent follow-up using discrete survival analysis.

Results

Among the 785 patients included in our analysis, the prevalence of persistent lupus anticoagulant as defined by the first two patient assessments was 4.3%. Annual assessment resulted in a prevalence of 6.6%, and using all 16 assessments resulted in a prevalence of 10.5%. The prevalence was substantially higher in men than in women, and in Caucasians than in African-Americans (p<0.01 for all comparisons). The rate of thrombosis was significantly elevated among those with persistently positive lupus anticoagulant by any definition (HR ranging from 2.75 to 3.42) relative to those without persistently positive lupus anticoagulant.

Conclusion

While there are other risk factors for thrombosis (including other antiphospholipid subtypes), more frequent testing (not limited to twice over 3 months) for lupus anticoagulant would be useful for identifying more patients with SLE at elevated risk for thrombosis.

Devastating Postpartum Complications in an Adolescent Linked to New-Onset Inflammatory Bowel Disease and Antiphospholipid Antibody Syndrome

Pregnancy can affect the severity of inflammatory bowel disease (IBD), and pregnant women with IBD are at a higher risk for venous thromboembolism compared with the general population. We report a previously healthy 16-year-old female who developed bloody diarrhea and venous thromboembolism following childbirth, with further evaluation revealing IBD and antiphospholipid antibody syndrome. This case highlights the impact pregnancy can have on IBD and other immunological disorders, and the potentially life-threatening risk of thrombosis in pregnant women with IBD.

Antiphospholipid antibodies in COVID-19: a meta-analysis and systematic review

BACKGROUND

Many studies reported high prevalence of antiphospholipid antibodies (aPL) in patients with COVID-19 raising questions about its true prevalence and its clinical impact on the disease course.

METHODS

We conducted a meta-analysis and a systematic review to examine the prevalence of aPL and its clinical impact in patients with COVID-19.

RESULTS

21 studies with a total of 1159 patients were included in our meta-analysis. Among patients hospitalised with COVID-19, the pooled prevalence rate of one or more aPL (IgM or IgG or IgA of anticardiolipin (aCL) or anti-ß2 glycoprotein (anti-ß2 GPI) or antiphosphatidylserine/prothrombin, or lupus anticoagulant (LA)) was 46.8% (95% CI 36.1% to 57.8%). The most frequent type of aPL found was LA, with pooled prevalence rate of 50.7% (95% CI 34.8% to 66.5%). Critically ill patients with COVID-19 had significantly higher prevalence of aCL (IgM or IgG) (28.8% vs 7.10%, p<0.0001) and anti-ß2 GPI (IgM or IgG) (12.0% vs 5.8%, p<0.0001) as compared with non-critically ill patients. However, there was no association between aPL positivity and mean levels of C reactive protein (mean difference was 32 (95% CI -15 to 79), p=0.18), D-dimer (mean difference was 34 (95% CI -194 to 273), p=0.77), mortality (1.46 (95% CI 0.29 to 7.29), p=0.65), invasive ventilation (1.22 (95% CI 0.51 to 2.91), p=0.65) and venous thromboembolism (1.38 (95% CI 0.57 to 3.37), p=0.48).

CONCLUSIONS

aPLs were detected in nearly half of patients with COVID-19, and higher prevalence of aPL was found in severe disease. However, there was no association between aPL positivity and disease outcomes including thrombosis, invasive ventilation and mortality. However, further studies are required to identify the clinical and pathological role of aPL in COVID-19.

High Incidence of Antiphospholipid Antibodies in Newly Diagnosed Patients With Lymphoma and a Proposed aPL Predictive Score

Given that the presence of antiphospholipid (aPL) antibodies has been proposed to be associated with thrombosis in newly diagnosed patients with lymphoma, we conducted a prospective cohort study on these patients. In all, 154 patients were enrolled. More than half were advanced-stage diffuse large B-cell lymphoma. Approximately one-third (35.7%) of the patients had the presence of aPLs, with single-, double-, and triple-aPL positivities of 29.9%, 5.2%, and 0.6%, respectively. Of the 154 patients, 8 (5.19%) developed symptomatic thrombosis during follow-up. There were no significant differences in the incidences of thrombosis for the aPL-positive and aPL-negative groups (5.5% vs 5.1%; P = 1.000). In a multivariate analysis, patients with male sex and lymphoma stage IV were significant risk factors for aPL positivity, with odds ratio [OR] = 2.22 (95% CI: 1.11-4.45), P = .025, and OR: 2.34 (95% CI: 1.17-4.67), P = .016, respectively. An aPL predictive score of ≥−1 was predictive of aPL positivity, with a sensitivity of 83.6% and specificity of 34.3%.

Anticardiolipin and other antiphospholipid antibodies in critically ill COVID-19 positive and negative patients

Background

Reports of severe COVID-19 being associated with thrombosis, antiphospholipid antibodies (APLA), and antiphospholipid syndrome have yielded disparate conclusions. Studies comparing patients with COVID-19 with contemporaneous controls of similar severity are lacking.

Methods

22 COVID-19⁺ and 20 COVID-19^– patients with respiratory failure admitted to intensive care were studied longitudinally. Demographic and clinical data were obtained from the day of admission. APLA testing included anticardiolipin (aCL), anti-β2glycoprotien 1 (β2GP1), antidomain 1 β2GP1 and antiphosphatidyl serine/prothrombin complex. Antinuclear antibodies (ANAs) were detected by immunofluorescence and antibodies to cytokines by a commercially available multiplexed array. Analysis of variance was used for continuous variables and Fisher’s exact test was used for categorical variables with α=0.05 and the false discovery rate at q=0.05.

Results

APLAs were predominantly IgG aCL (48%), followed by IgM (21%) in all patients, with a tendency towards higher frequency among the COVID-19⁺. aCL was not associated with surrogate markers of thrombosis but IgG aCL was strongly associated with worse disease severity and higher ANA titres regardless of COVID-19 status. An association between aCL and anticytokine autoantibodies tended to be higher among the COVID-19⁺.

Conclusions

Positive APLA serology was associated with more severe disease regardless of COVID-19 status.

Trial registration number

NCT04747782

European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) SLE classification criteria item performance

BACKGROUND/OBJECTIVES

The European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) 2019 classification criteria for systemic lupus erythematosus system showed high specificity, while attaining also high sensitivity. We hereby analysed the performance of the individual criteria items and their contribution to the overall performance of the criteria.

METHODS

We combined the EULAR/ACR derivation and validation cohorts for a total of 1197 systemic lupus erythematosus (SLE) and n=1074 non-SLE patients with a variety of conditions mimicking SLE, such as other autoimmune diseases, and calculated the sensitivity and specificity for antinuclear antibodies (ANA) and the 23 specific criteria items. We also tested performance omitting the EULAR/ACR criteria attribution rule, which defines that items are only counted if not more likely explained by a cause other than SLE.

RESULTS

Positive ANA, the new entry criterion, was 99.5% sensitive, but only 19.4% specific, against a non-SLE population that included other inflammatory rheumatic, infectious, malignant and metabolic diseases. The specific criteria items were highly variable in sensitivity (from 0.42% for delirium and 1.84% for psychosis to 75.6% for antibodies to double-stranded DNA), but their specificity was uniformly high, with low C3 or C4 (83.0%) and leucopenia <4.000/mm³ (83.8%) at the lowest end. Unexplained fever was 95.3% specific in this cohort. Applying the attribution rule improved specificity, particularly for joint involvement.

CONCLUSIONS

Changing the position of the highly sensitive, non-specific ANA to an entry criterion and the attribution rule resulted in a specificity of >80% for all items, explaining the higher overall specificity of the criteria set.

DOAC-Stop in lupus anticoagulant testing: Direct oral anticoagulant interference removed in most samples

BACKGROUND

The use of direct oral anticoagulants (DOACs) is a convenient therapeutic option for patients at risk of thrombosis. DOACs interfere with clot-based testing for the identification of lupus anticoagulant antibodies (LACs) in patients with antiphospholipid syndrome (APS), a common cause of acquired thrombotic disease.

OBJECTIVES

To evaluate a commercially available reagent DOAC-Stop for the removal of DOAC interference encountered in LAC testing.

PATIENTS/METHODS

We collected a cohort of 73 test samples from patients on DOAC therapy identified at a large institutional coagulation laboratory from March to December 2019, along with samples from 40 LAC positive and negative control patients not on therapy. Samples were treated with DOAC-Stop and tested for anti-Xa activity and thrombin time for the removal of apixaban, rivaroxaban, argatroban, and dabigatran activity from patient samples. Treated and untreated samples were tested using the activated partial thromboplastin time, silica clotting time, and dilute Russell's viper venom time to evaluate the reliability and utility of DOAC-Stop.

RESULTS

DOAC-Stop markedly reduced DOAC interference from test samples (P < .05). DOAC-Stop had no effect on LAC testing in the absence of DOAC therapy, permitting the identification of all LAC positive and negative controls. DOAC-Stop removed false positives and false negatives resulting from DOAC interference and allows the identification of patients meeting criteria for the diagnosis of APS by LAC testing, as well as the detection of patients on rivaroxaban who are triple positive for APS.

CONCLUSIONS

DOAC-Stop is an effective adjunct for the clinical laboratory faced with DOAC interference in LAC testing.

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

BACKGROUND

High incidence of thrombosis in COVID-19 patients indicates a hypercoagulable state. Hence, exploring the involvement of antiphospholipid antibodies (aPL) in these patients is of interest.

OBJECTIVES

To illustrate the incidence of criteria (lupus anticoagulant [LAC], anticardiolipin [aCL] immunoglobulin G [IgG]/IgM, antibeta2-glycoprotein I antibodies [aβ2GPI] IgG/IgM) and noncriteria (anti-phosphatidyl serine/prothrombin [aPS/PT], aCL, and aβ2GPI IgA) aPL in a consecutive cohort of critically ill SARS-CoV-2 patients, their association with thrombosis, antibody profile and titers of aPL.

PATIENTS/METHODS

Thirty-one consecutive confirmed COVID-19 patients admitted to the intensive care unit were included. aPL were measured at one time point, with part of the aPL-positive patients retested after 1 month.

RESULTS

Sixteen patients were single LAC-positive, two triple-positive, one double-positive, one single aCL, and three aCL IgG and LAC positive. Seven of nine thrombotic patients had at least one aPL. Sixteen of 22 patients without thrombosis were aPL positive, amongst them two triple positives. Nine of 10 retested LAC-positive patients were negative on a second occasion, as well as the double-positive patient. Seven patients were aPS/PT-positive associated to LAC. Three patients were aCL and aβ2GPI IgA-positive.

CONCLUSION

Our observations support the frequent single LAC positivity during (acute phase) observed in COVID-19 infection; however, not clearly related to thrombotic complications. Triple aPL positivity and high aCL/aβ2GPI titers are rare. Repeat testing suggests aPL to be mostly transient. Further studies and international registration of aPL should improve understanding the role of aPL in thrombotic COVID-19 patients.

Comparative study of obstetric antiphospholipid syndrome (OAPS) and non-criteria obstetric APS (NC-OAPS): report of 1640 cases from the EUROAPS registry

OBJECTIVES

To compare clinical features, laboratory data and fetal-maternal outcomes between 1000 women with obstetric APS (OAPS) and 640 with aPL-related obstetric complications not fulfilling Sydney criteria (non-criteria OAPS, NC-OAPS).

METHODS

This was a retrospective and prospective multicentre study from the European Registry on Obstetric Antiphospholipid Syndrome.

RESULTS

A total of 1650 women with 5251 episodes, 3601 of which were historical and 1650 latest episodes, were included. Altogether, 1000 cases (OAPS group) fulfilled the Sydney classification criteria and 650 (NC-OAPS group) did not. Ten NC-OAPS cases were excluded for presenting thrombosis during follow-up. All cases were classified as category I (triple positivity or double positivity for aPL) or category II (simple positivity). Overall, aPL laboratory categories showed significant differences: 29.20% in OAPS vs 17.96% in NC-OAPS (P < 0.0001) for category I, and 70.8% in OAPS vs 82% in NC-OAPS (P < 0.0001) for category II. Significant differences were observed when current obstetric complications were compared (P < 0.001). However, major differences between groups were not observed in treatment rates, livebirths and thrombotic complications. In the NC-OAPS group, 176/640 (27.5%) did not fulfil Sydney clinical criteria (subgroup A), 175/640 (27.34%) had a low titre and/or non-persistent aPL positivity but did meet the clinical criteria (subgroup B) and 289/640 (45.15%) had a high aPL titre but did not fulfil Sydney clinical criteria (subgroup C).

CONCLUSION

Significant clinical and laboratory differences were found between groups. Fetal-maternal outcomes were similar in both groups when treated. These results suggest that we could improve our clinical practice with better understanding of NC-OAPS patients.

Mononeuritis Multiplex Associated With Antiphospholipid Antibodies

In this article, we report the case of a 43-year-old male patient with mononeuritis multiplex associated with antiphospholipid antibodies. The patient had no other clinical or laboratory features of other systemic or autoimmune diseases or systemic vasculitis. He was treated with oral anticoagulant and mycophenolate mofetil, and is progressing favorably.

Congenital protein C deficiency and thrombosis in a dog

Congenital protein C deficiency is an important cause of thrombosis in humans but is not described in dogs. A 4‐year‐old Hungarian Vizsla was presented for investigation of acute onset of ascites. Computed tomography of the chest and abdomen and echocardiography confirmed a large thrombus within the right ventricle. A cause for thrombosis was not initially identified. The clinical signs resolved rapidly and the dog was administered clopidogrel and discharged. Plasma protein C activity measured 2 and 6 weeks later was markedly lower than expected on both occasions. All known causes of acquired protein C deficiency were excluded, and the dog was diagnosed with a congenital protein C deficiency. After diagnosis, the administration of clopidogrel was stopped and administration of rivaroxaban was started. The dog remains well with no evidence of recurrent thrombosis with 6 months of follow‐up.

Immune Complexes of Beta-2-Glycoprotein I and IgA Antiphospholipid Antibodies Identify Patients With Elevated Risk of Thrombosis and Early Mortality After Heart Transplantation

Background: The presence of anti-Beta 2 glycoprotein antibodies (aB2GP1) of IgA isotype is common in patients with functional impairment of the organs in which B2GP1 is elaborated. Pretransplant IgA aB2GP1 has been associated with increased risk of thrombosis in kidney and heart transplanted patients and has also been related with early mortality after heart transplantation. Circulating immune complexes between IgA and B2GP1 (B2A-CIC) have been described in the blood of patients positive for IgA aB2GP1 with thrombotic clinical symptoms. In kidney transplanted patients, B2A-CIC is a biomarker that predicts which patients IgA aB2GP1 positive are at risk of thrombosis events following kidney transplantation and may lead to early prophylactic treatment. The prevalence of B2A-CIC and its relation with outcomes after heart transplantation is not known.

Methods: Follow-up study based on 151 consecutive patients who received a heart transplant. Autoantibodies and B2A-CIC were quantified in pre-transplant serum samples. Three groups of patients were followed-up for 2 years: Group-1, positive for IgA aB2GP1 and B2A-CIC (N = 19). Group-2, only positive for IgA aB2GP1 (N = 28). Group-0 (control group): IgA aB2GP1 negative (N = 104).

Results: Kaplan-Meir survival analysis showed that mortality in B2A-CIC positive was higher than group-0 at 3 months (HR:5.08; 95%CI: 1.36–19.01) and at 2 years (HR:3.82; 95%CI: 1.54–12.66). No significant differences were observed between group-2 and group-0. Multivariate analysis identified B2A-CIC as the most important independent risk factor for early mortality (OR = 6.12; 95% CI: 1.93–19.4). Post-transplant incidence of thrombosis was significantly higher in B2A-CIC positive patients than in the control group (OR: 6.42; 95%CI: 2.1–19.63). Multivariate analysis identified the presence of B2A-CIC (OR: 6.13; 95%CI: 2.1–19.63) and the pre-transplant habit of smoking actively (OR: 4.18; 95%CI: 1.35–12.94) as independent risk factor for thrombosis. The proportion of patients who had thrombotic events or died in the first trimester was significantly higher in group-1 (73.7%) than in group-0 (16.3%; p < 0.001) and in group-2 (39.3%; p = 0.02). Multivariate analysis identified B2A-CIC as the main independent risk factor for early outcomes (mortality or thrombosis) in the first 3 months after heart transplant (OR = 11.42, 95% CI: 1.69–9.68).

Conclusion: B2A-CIC are a predictor of early mortality and thrombosis after heart transplant.

Diagnostic performance of aPS/PT antibodies in neuropsychiatric lupus and cardiovascular complications of systemic lupus erythematosus

Background: Systemic lupus erythematosus (SLE) is associated with a constellation of complications affecting multiple organs, including neuropsychiatric manifestations (NPSLE) and ischaemic events, leading to increased long-term morbidity. Antiphospholipid antibodies (aPL) are a major determinant of vascular inflammation and thromboembolic risk. The diagnostic role of anti-phosphatidylserine/prothrombin (aPS/PT) antibodies in this setting is incompletely defined.Aim: To verify whether aPS/PT add to diagnostics and disease stratification in patients with SLE with or without other aPL.Methods: 131 consecutive patients were studied, including 20 patients with SLE and secondary antiphospholipid syndrome (APS). aPS/PT IgG and IgM were assessed through ELISA and patients were stratified based on the presence of other aPL, on their clinical and laboratory features at time of blood sampling and on their clinical history. Synthetic indices of disease activity, chronic damage and cardiovascular risk were calculated at time of venipuncture.Results: Fifty-one (38.9%) patients with SLE had aPS/PT and 15 (11.5%) patients had aPS/PT as the only aPL (aPS/PT-only). aPS/PT-only patients had a significantly higher prevalence of NPSLE than quadruple aPL-negative patients (p = .007). Patients with aPS/PT were more likely to have a history of ischaemia, thrombocytopenia and Libman-Sacks' endocarditis. The presence of aPS/PT also associated with previous accrual of at least one damage item (p = .043), but had limited predictive values for damage progression in the short term.Conclusion: aPS/PT antibodies provide non-redundant information that could contribute to risk assessment and stratification of patients with SLE.

Detection of non-criteria autoantibodies in women without apparent causes for pregnancy loss

Background

Some of the non‐criteria autoantibodies, especially non‐conventional antiphospholipid (aPL) antibodies, were present with high prevalence in sporadic miscarriages and recurrent pregnant loss. However, whether these autoantibodies are associated with miscarriage patients without apparent causes remain unclear.

Methods

The subjects were recruited from the female patients visiting the Infertility Center at the Beijing Obstetrics and Gynecology Hospital from January 2017 to March 2018. The women who experienced one sporadic miscarriage (n = 89) or recurrent pregnancy loss (n = 125) were enrolled. The control participants (n = 59) were those women with normal pregnancy history and with no miscarriage or thrombosis experience. The collected serum specimens from above patients and controls were subjected to the 13 non‐criteria autoantibody examinations, targeting non‐conventional phospholipids, thyroid, sperm, endometrial, and anti‐nuclear antigens.

Results

When compared with the controls, the following non‐criteria antibodies stood out in present study with significantly increased frequency and were listed in the order of decreasing positive rates: aPE IgM (40.0%), ANA (15.2%), aEM IgG (13.6%), aPE IgG (12.8%), and aPT IgM (10.4%). Except for ANA, the presence of aPE IgM, aEM IgG, aPE IgG, and aPT IgM was not associated with positivity of LA tests. In receiver operating characteristic analyses, the combined aPE IgG and aEM IgG biomarker panel had the best discriminating power between miscarriage patients and healthy controls.

Conclusion

Our findings suggested that the non‐criteria could be included as part of the pregnancy loss evaluation when apparent causes are absent, and the conventional aPLs tests failed to provide interpretations.

Epstein Barr Virus-induced Antiphospholipid Antibodies Resulting in Splenic Infarct: A Case Report

Splenic infarction is a rare cause of abdominal pain. We herein reported a unique case of a 30-year-old male patient who developed a splenic infarct during the acute phase of Epstein-Barr virus (EBV)-associated infectious mononucleosis (IM) and was subsequently found to have the presence of antiphospholipid antibodies (APA).

Presence of Immune Complexes of IgG/IgM Bound to B2-glycoprotein I Is Associated With Non-criteria Clinical Manifestations in Patients With Antiphospholipid Syndrome

Background: Antiphospholipid syndrome (APS) is an acquired autoimmune disorder defined by the presence of both clinical (thromboembolic events or pregnancy morbidity) and laboratory (antiphospholipid antibodies, aPL) manifestations. Despite their importance, several clinical manifestations strongly associated with APS such as livedo reticularis (LR), thrombocytopenia, sicca-ophthalmic(sicca), heart, or neurological manifestations are not included in the APS clinical classification criteria. Circulating immune complexes (CIC) formed by Beta-2-glycoprotein I (B2GPI) and aPL (B2-CIC) have been described and their presence has been related with thrombotic events.

Methods: Cross-sectional and observational cohort study in APS patients with thrombotic symptomatology.

Setting and Participants: Fifty-seven patients from the University Hospital Center Bezanijska Kosa (Belgrade, Serbia) who met the APS classification criteria (35 with primary APS and 22 with APS associated to systemic lupus erythematosus). This study aimed to determine the prevalence of B2-CIC in APS patients and to evaluate their association with clinical manifestations of APS not included in the classification criteria.

Results: B2-CIC prevalence in APS patients was 19.3%. The presence of thrombocytopenia (OR:5.7), livedo reticularis (OR:5.6), sicca (OR:12.6), and leukopenia (OR:5.6) was significantly higher in patients with B2-CIC than in the rest of APS patients. C3 and C4 complement factor levels were significantly lower in B2-CIC positive patients, which suggests a greater consumption of complement. Patients with quadruple aPL positivity (triple aPL-positivity plus the presence of B2-CIC) showed a higher prevalence of thrombocytopenia, leucopenia and LR than those with single/double aPL-positivity. No significant differences were found in the frequencies observed in patients with triple-only vs. single/double aPL-positivity. There were no significant differences between patients with primary APS and lupus-associated APS regarding the prevalence of B2-CIC and outcomes.

Conclusions: Presence of B2-CIC is strongly associated with several non-criteria clinical manifestations related to APS and to higher complement consumption. More studies are required to better understand the clinical significance of B2-CIC.

Antibodies: The major participants in maternal-fetal interaction

The aim of this study is to improve our understanding of the mechanisms involved in maternal-fetal immune tolerance. We searched the related literatures and overviewed the major antibodies associated with pregnancy and described in details their possible roles in mediating maternal-fetal interactions. Antibodies classified into different types based on their functional or structural characteristics were summarized, including immunoglobulin G, blocking antibody, nonprecipitating asymmetric antibody, antiphospholipid antibody, antitrophoblast antibody and antipaternal antibody. The presence and levels of various circulating antibodies in pregnancy may play a crucial role in the occurrence, development and termination of pregnancy.

Psycho-rheumatic Integration in Systemic Lupus Erythematosus: An Insight into Antibodies Causing Neuropsychiatric Changes

The main purpose of this paper is to bring together all the antibodies and markers related to neurological and psychiatric manifestations in systemic lupus erythematosus and also the pharmacology that could help treat these symptoms. Existing research data regarding specific antibodies involved in the disease process and drugs that were being studied was collected and analyzed. After reviewing the studies published by various authors, symptoms were shown to be mainly caused by antibodies against N-methyl-D-aspartate receptor (NMDAR) antibodies, anti-endothelial, anti-ribosomal P, antiphospholipid antibodies, cytokines like interferons and chemokines. The monoclonal antibody rituximab has shown to be beneficial in some of the cases. Based on all the articles reviewed, the antibodies and cytokines showed the most effective evidence in causing the different manifestations of neuropsychiatric systemic lupus erythematosus (NPSLE), but studies regarding the drugs being effective against all the symptoms are inconclusive as there are very few studies. Further research to support the drug’s effectiveness in managing the symptoms is needed. More studies are needed regarding early diagnosis of NPSLE using the antibodies as biomarkers as it could help in preventing these manifestations.

Coexistence of anti-β2-glycoprotein I domain I and anti-phosphatidylserine/prothrombin antibodies suggests strong thrombotic risk

BACKGROUND

Highly specific assays for measuring antiphospholipid antibodies (aPLs) are required for accurate assessment of thrombotic risk. aPLs against β2-glycoprotein I domain I (anti-β2GPIdI) and against prothrombin complexed with phosphatidylserine (anti-PS/PT) have been recently identified as being associated with a hypercoagulable state. This study evaluated the synergism between anti-β2GPIdI and anti-PS/PT for predicting thrombotic events.

METHODS

A total of 180 patients with clinical suspicion of hypercoagulability were evaluated. The plasma levels of lupus anticoagulant (LA) and antibodies against anticardiolipin (anti-CL) (IgG and IgM), β2GPI (IgG and IgM), PS/PT (IgG and IgM), and β2GPI dI (IgG) were measured.

RESULTS

IgG anti-β2GPIdI and LA were highly associated with thrombosis. Mean values and positivity rates of IgG anti-β2GPI dI and IgG anti-PS/PT were significantly higher in the triple-positive group (LA+, IgG anti-CL+, IgG anti-β2GPI+) than in the other groups. Interestingly, the thrombotic risk [odds ratio (OR) 24.400, 95% confidence interval (CI) 1.976-63.273, p<0.001] of the newly defined triple positive group (LA+, IgG anti-CL+, IgG anti-β2GPIdI+; OR 11.182, 95% CI 1.976-63.273, p=0.006) was more than twice that of the triple-positive group (LA+, IgG anti-CL+, IgG anti-β2GPI+). Double positivity for IgG anti-PS/PT and IgG anti-β2GPI also indicated significant thrombotic risk (OR 7.467, 95% CI 2.350-23.729, p=0.001). Furthermore, the thrombotic risk associated with double positivity for IgG anti-PS/PT and IgG anti-β2GPIdI was markedly elevated (OR 33.654, 95% CI 6.322-179.141, p<0.001).

CONCLUSIONS

Our data suggest that simultaneous measurement of IgG anti-β2GPIdI and IgG anti-PS/PT may improve clinical decision-making for aPL-positive patients.

Familial Q fever clustering with variable manifestations imitating infectious and autoimmune disease

Q fever, caused by Coxiella burnetii, can present as an outbreak of acute disease ranging from asymptomatic disease, pneumonia, hepatitis or fever of unknown origin, which can progress to a chronic disease, most frequently endocarditis. The occurrence of Q fever within families is rarely described, and in most cases presents with uniform acute disease manifestations. Here we present a familial cluster of Q fever presenting as highly variable synchronous manifestations in four of five family members, including prolonged fever of unknown origin, asymptomatic carrier state, hepatitis, and chronic endocarditis developing in the absence of previous symptoms. This case series highlights the possibility of Q fever developing in cohabitated individuals with highly variable symptoms masking the common disease etiology. Screening of all exposed individuals, even those not clinically suspected to be infected, may enable to better identify, treat and prevent progression to chronic disease.

Antiphospholipid syndrome in renal transplantation

Antiphospholipid syndrome (APS) may occur in isolation or in association with systemic lupus erythematosus (SLE), with the potential to cause renal failure via several distinct pathologies. Renal transplantation in the presence of APS carries a risk of early graft loss from arterial or venous thrombosis, or thrombotic microangiopathy (TMA). Whilst perioperative anticoagulation reduces the risk of large vessel thrombosis, it may result in significant haemorrhage, and its efficacy in preventing post-transplant TMA is uncertain. Here, we report a patient with end-stage kidney disease (ESKD) due to lupus nephritis and APS, in whom allograft TMA developed soon after transplantation despite partial anticoagulation. TMA resolved with plasma exchange-based therapy albeit with some irreversible graft damage and renal impairment. We discuss the differential diagnosis of post-transplant TMA, and current treatment options.

Antiphospholipid IgM antibody response in acute and chronic Mycobacterium tuberculosis mouse infection model

BACKGROUND AND AIMS

The clinical management of tuberculosis (TB) could be greatly improved by an affordable biomarker test to monitor treatment response. Here, we examined changes in immunoglobulin M (IgM) antibody response to lipids as a potential biomarker for monitoring TB treatment in an experimental mouse model.

METHODS

We performed enzyme-linked immunosorbent assay to investigate changes in IgM antibody response against cardiolipin (CL), phosphatidylcholine (PTC), phosphatidylethanolamine (PE), phosphatidylinositol (PI) and sphingolipid (SL) in BALB/c mice that were treated after being infected with Mycobacterium tuberculosis for 4 weeks (acute infection) and 20 weeks (chronic infection). Cytokine levels [interleukin (IL)-5, IL-10, interferon-gamma (IFN-γ), monocyte chemoattractant protein-1 (MCP-1)] in lung and spleen homogenates as well as in blood were also compared.

RESULTS

In both acutely and chronically infected mice, lungs were sterilised of M. tuberculosis infection after 8 weeks of treatment. The IgM response to CL, PTC, PE, PI and SL were consistently elevated throughout the course of infection in chronically infected mice compared with acutely infected mice. In acutely infected mice, the IgM antibody response against CL significantly decreased after 8 weeks of treatment, but not against other lipids. In chronically infected mice, the IgM response showed no significant changes against any of the lipids after 8 weeks of treatment. Of the cytokines examined, only MCP-1 levels in lungs decreased significantly after treatment.

CONCLUSION

These findings demonstrate that antilipid IgM antibody can remain elevated in chronically infected mice, but with treatment, only anti-CL IgM antibody levels decreased together with M. tuberculosis bacterial burden in acutely infected mice. Treatment did not affect antilipid IgM levels in chronically infected mice.

Anti-Phosphatidylserine-Prothrombin Antibodies are Associated with Outcome in a TIA Cohort

BACKGROUND

Antiphospholipid antibodies (aPLs) have been associated with thrombosis in the antiphospholipid antibody syndrome (APS) and with atherosclerotic vascular events in patients without APS. We examined the significance of aPLs in transient ischemic attack (TIA).

PATIENTS/METHODS

Patients with TIA <48 h from symptom onset were prospectively enrolled. Traditional aPLs, including anticardiolipin and β2-glycoprotein-I (β2GPI), and newer aPLs, including anti-phosphatidylserine/prothrombin (aPS/PT), β2GPI Domain 4/5 and β2GPI Domain 1 were measured. Primary outcome was a composite of stroke or death within 90 days or identification of a high risk stroke mechanism. Secondary outcomes were stroke or death and the presence of clinical/sub-clinical atherosclerosis.

RESULTS

Over 4.5 years, 167 patients were enrolled. Forty one patients (25%) had the composite endpoint. Antibodies were measured in 158 subjects. aPS/PT IgG antibodies were significantly associated with stroke/death (OR 16.3, 95% CI 2.3-116.7, p = 0.005) and were non-significantly associated with the composite endpoint (OR 4.7, 95% CI 0.8-29.2, p = 0.10). In multivariate analysis adjusting for ABCD(2) risk score, aPS/PT IgG remained associated with stroke/death (OR 15.7, 95% CI 2.0-125.6, p = 0.009). Other aPLs were not associated with clinical outcome and no association between APLs and atherosclerosis was identified.

CONCLUSION

In contrast to other aPLs, aPS/PT IgG antibodies are independently associated with stroke or death in patients with TIA.

Anticardiolipin antibodies in patients with type 2 diabetes mellitus

BACKGROUND

There is controversy about an increased prevalence of antiphospholipid antibodies in diabetic patients. The possible implications are little known.

METHODS

We prospectively studied all consecutive outpatients with type 2 diabetes mellitus (DM) attended to in an Internal Medicine office. IgM and IgG anticardiolipin antibodies (ACA) were determined by standardized enzyme-linked immunoassay.

RESULTS

Fifty-six patients were included. Only one patient (1.8%) had a titer of IgM ACA higher than 15 MPL units and no patient had a titer of IgG ACA higher than 15 GPL units. Six patients (10.7%) had low IgM ACA titers (4-15 MPL units) and 18 patients (32.1%) had low IgG ACA titers (4-15 GPL units). There were no differences in the frequencies of a low IgM or IgG ACA titer or in the means of IgM and IgG ACA titers in patients with complicated and uncomplicated DM, with and without cardiovascular disease, with and without nephropathy, or with and without retinopathy.

CONCLUSIONS

Moderate to high ACA titers must be exceptional in patients with type 2 DM. Low ACA titers may occur in patients with type 2 DM. These low titers do not seem to be associated with complicated DM, cardiovascular disease, nephropathy or retinopathy.