97 research outputs found
Thrombotic antiphospholipid syndrome: A practical guide to diagnosis and management
Thrombotic antiphospholipid syndrome (APS) is characterised by venous, arterial and/or small vessel thrombosis in the context of persistently positive antiphospholipid antibodies (aPL). The diagnosis and management of thrombotic APS continues to prove challenging for clinicians. We provide a practical guide to the diagnosis of APS including who to test for aPL and which tests to do. We also consider clinical practice points on the management of venous, arterial and small vessel thrombosis, in the context of first and recurrent thrombotic events. Non-criteria manifestations of APS are reviewed. An approach to recurrent thrombosis and anticoagulant-refractory APS is discussed, with options including increasing the anticoagulation intensity of vitamin K antagonists, switching to low-molecular-weight-heparin, the use of fondaparinux and/or the addition of antiplatelet treatment. Adjunctive options such as vitamin D, hydroxychloroquine and statins are also addressed
Coexistent antiphospholipid syndrome and myeloproliferative neoplasm
Antiphospholipid syndrome (APS) and myeloproliferative neoplasms (MPN) are associated with an increased risk of thrombosis. The optimal management of patients with coexistent APS and MPN has not been defined. A single centre and systematic literature review of patients with coexistent APS and MPN was performed. Cases were divided into two groups based on whether they met international consensus criteria for APS. Of the 12 studies identified, eight were excluded (leaving five of a total 54 patients), as although antiphospholipid antibodies (aPL) were documented, the diagnosis of APS was not conclusively demonstrated. Another ten patients with definite APS were identified at our centre. Fifteen patients (ten females, five males) were therefore included in this analysis (eleven definite APS and four highly likely), median age 44 (range: 13–71) years. Nine had polycythaemia vera and six, essential thrombocythaemia. Thirteen of the 15 patients (86.7%) had thrombotic APS (seven with initial venous events and six arterial) and two (13.3%) had obstetric APS. Nine patients were single-positive, and six double-positive for aPL. None were triple aPL-positive. Four patients at our centre had recurrent thrombotic/obstetric events, including while on anticoagulation/antiplatelet treatment
Management of anticoagulant-refractory thrombotic antiphospholipid syndrome
Lifelong anticoagulation with warfarin or alternative vitamin K antagonist is the standard anticoagulant treatment for thrombotic antiphospholipid syndrome. Anticoagulant-refractory thrombotic antiphospholipid syndrome can be broadly defined as breakthrough thrombosis while on standard oral anticoagulation treatment and its management is a major challenge given the serious nature of the thrombotic disease observed, which has become refractory to oral anticoagulation. The factors (genetic and cellular) that cause anticoagulant-refractory thrombotic antiphospholipid syndrome are now better understood. However, efforts to use this greater understanding have not yet transformed the capacity to treat it successfully in many patients. In this Viewpoint, we review the factors that are likely to be contributing to the cause of this syndrome and consider how they might be modified or inhibited. We also discuss management, including general strategies to minimise thrombotic risk, intensification of anticoagulation, addition of an antiplatelet agent, adjunctive treatment for thrombosis, immunomodulatory therapy, complement inhibition, vascular options, and future potential therapeutic targets
High rates of venous and arterial thrombotic events in patients with POEMS syndrome: results from the UCLH (UK) POEMS Registry
Arterial and venous thromboses occur in patients with POEMS (polyneuropathy,
organomegaly, endocrinopathy, M-protein level, and skin changes) syndrome at
a previously reported rate of 20%. We reviewed the University College London Hospitals
(UCLH) POEMS Registry to determine the rate of venous thromboembolism (VTE), arterial
events, and risk factors. This registry, established in 1999 and comprising 103 patients at the
time of this study, is the largest single-center cohort in Europe. Of the 83 assessable patients,
median age at presentation was 52 years (range, 31-84). Twenty-five patients experienced
clinically apparent arterial or venous events, and 2 had concurrent arterial and venous
thromboses. Eleven patients had VTEs, including deep vein thrombosis (DVT; 3 of 11),
pulmonary embolism (4 of 11), and peripherally inserted central catheter–associated DVT,
which occurred during autologous stem cell transplantation (3 of 11). Sixteen patients
experienced arterial events: stroke (7 of 16), peripheral arterial occlusion (5 of 16),
myocardial infarction (3 of 16), and microvascular disease (1 of 16), with no discernible
relationship with thrombocytosis or polycythemia. Thirty percent of POEMS patients have
arterial and venous thromboses, higher than previously reported. There were more arterial
than venous events, and most occurred during active disease, before the start of
chemotherapy, indicating the need for a preemptive approach to thromboprophylaxi
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Problematic social networking site use in Turkey: a large-scale national survey study
The current research landscape has witnessed a marked increase in investigations concerning problematic social networking site use (PSNSU). However, prior studies exploring the prevalence and determinants of PSNSU have predominantly relied on limited and diverse participant samples. To address this gap, the present study examined the measurement dimensions and psychological correlates-namely psychiatric distress, alexithymia, attachment, and wellbeing-of PSNSU within a large number of Turkish community individuals (N=24,380, 50% men, Mage=31.79 years, SD=10.86). Participants completed a survey comprising psychometric scales regarding the aforementioned variables. Utilizing item response theory, 2.8% of the participants were found to exhibit susceptibility to PSNSU. Hierarchical regression analysis showed significant positive associations between PSNSU and factors including younger age, single marital status, alcohol consumption, cigarette smoking, psychiatric distress, affective states, and attachment styles. These findings underscore the importance of research regarding PSNSU among individuals in the Turkish community and highlights the involvement of various socio-demographic and adverse psychological factors in driving this problematic behavior
A Simulation-Assisted Non-destructive Approach for Permittivity Measurement Using an Open-Ended Microwave Waveguide
A new convenient and non-destructive permittivity measurement method is presented. No physical cut of specimens is needed here for material characterisation. In the setup, the material under test is placed in the near-field region of a microwave open-ended waveguide. An electromagnetic model of the setup is built in the Computer Simulation Technology simulation software. Employing optimisation, the permittivity is obtained from the measured reflection coefficients S11. Using the same technique, the effect of the model size is investigated that could reduce the modelling effort for large structures. The efficiency of a traditional method (i.e., Newton) and an intelligent algorithm (i.e. particle swarm optimisation) for permittivity calculation is thoroughly studied and compared. The proposed methodology is validated by experimental data. It is demonstrated that the proposed method can provide more accurate permittivity results than the intrusive in-waveguide measurement. The proposed methodology can contribute to electromagnetic analysis, thickness measurement and non-destructive evaluation
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Rivaroxaban for stroke patients with antiphospholipid syndrome (RISAPS): protocol for a randomized controlled, phase IIb proof-of-principle trial
Background
Optimal secondary prevention antithrombotic therapy for patients with antiphospholipid syndrome (APS)-associated ischemic stroke, transient ischemic attack, or other ischemic brain injury is undefined. The standard of care, warfarin or other vitamin K antagonists at standard or high intensity (international normalized ratio (INR) target range 2.0-3.0/3.0-4.0, respectively), has well-recognized limitations. Direct oral anticoagulants have several advantages over warfarin, and the potential role of high-dose direct oral anticoagulants vs high-intensity warfarin in this setting merits investigation.
Objectives
The Rivaroxaban for Stroke patients with APS trial (RISAPS) seeks to determine whether high-dose rivaroxaban could represent a safe and effective alternative to high-intensity warfarin in adult patients with APS and previous ischemic stroke, transient ischemic attack, or other ischemic brain manifestations.
Methods
This phase IIb prospective, randomized, controlled, noninferiority, open-label, proof-of-principle trial compares rivaroxaban 15 mg twice daily vs warfarin, target INR range 3.0-4.0. The sample size target is 40 participants. Triple antiphospholipid antibody-positive patients are excluded. The primary efficacy outcome is the rate of change in brain white matter hyperintensity volume on magnetic resonance imaging, a surrogate marker of presumed ischemic damage, between baseline and 24 months follow-up. Secondary outcomes include additional neuroradiological and clinical measures of efficacy and safety. Exploratory outcomes include high-dose rivaroxaban pharmacokinetic modeling.
Conclusion
Should RISAPS demonstrate noninferior efficacy and safety of high-dose rivaroxaban in this APS subgroup, it could justify larger prospective randomized controlled trials
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