Pediatric antiphospholipid syndrome: clinical features and therapeutic interventions in a single center retrospective case series.

BACKGROUND/PURPOSE: Pediatric antiphospholipid syndrome (APS) is a thromboinflammatory disease characterized by the presence of circulating antiphospholipid antibodies and either thrombotic events or pregnancy morbidity. The objective of this study was to review a large institution's experience to better understand the characteristics of children with APS. METHODS: We conducted a retrospective review of pediatric APS at a tertiary referral center. The electronic medical record system was queried from 2000 through 2019, and 21 cases were included based on meeting the revised Sapporo Classification criteria by age 18 or younger. Comparisons between primary and secondary APS patients were made with two-tailed t-tests. RESULTS: Twenty-one patients were included with a median age at diagnosis of 16 years and median follow-up of 5.8 years. Secondary APS was slightly more common than primary APS (11 vs. 10 cases) and was primarily diagnosed in the context of systemic lupus erythematosus. Two thirds of patients (67%) also had "non-criteria" manifestations of APS including thrombocytopenia, autoimmune hemolytic anemia, and livedo reticularis/racemosa. Almost half of patients (43%) had recurrent thrombosis, typically when patients were subtherapeutic or non-adherent with anticoagulation. Damage Index in Patients with Thrombotic APS (DIAPS) scores indicated a chronic burden of disease in both primary and secondary APS patients. CONCLUSION: This case series of pediatric APS provides important context regarding disease phenotypes displayed by children with APS. High prevalence of non-criteria clinical manifestations highlights the need to consider these characteristics when developing pediatric-specific classification criteria and when considering this relatively rare diagnosis in pediatric practice.

The assessment of patients with the antiphospholipid antibody syndrome: where are we now?

The antiphospholipid antibody syndrome (APS), a chronic autoimmune thrombophilia with an increased mortality and morbidity, has been recognized for more than three decades. Unlike other autoimmune rheumatic conditions such as systemic lupus erythematosus, myositis and Sjögren's syndrome, relatively few attempts have been made to develop activity, damage or disease-specific quality of life indices for APS. In this review of the literature, we consider those attempts that have been made to develop assessment tools for patients with APS, but also reflect upon the nature of the condition, to discuss, in particular, whether an activity index is appropriate for this disease.

New insights into antiphospholipid-related endothelial dysfunction by assessment of vascular glycocalyx layer: results from a preliminary cross-sectional study.

INTRODUCTION: Antiphospholipid syndrome (APS) is associated with greater atherothrombotic risk and endothelial dysfunction, suggesting that endothelial glycocalyx is impaired in this disease. OBJECTIVES: The aim was to investigate the endothelial glycocalyx and the relationship between glycocalyx markers, endothelial dysfunction parameters and atherosclerotic markers in APS. METHODS: A total of 15 primary arterial APS patients and healthy controls were included in the study. Glycocalyx was assessed in both groups by sublingual sidestream dark field imaging and syndecan-1 plasma level. Endothelial function was evaluated by brachial artery flow-mediated dilatation (FMD) and early atherosclerosis by carotid intima media thickness (IMT). Thrombotic profile was also performed by measuring the plasma level of the tissue factor (TF). RESULTS: APS patients had significantly increased syndecan-1 plasma level 38.6 ± 5.0 pg/ml vs. 19.1 ± 3.5 pg/ml; p < 0.01 and a reduced glycocalyx thickness 0.26 ± 0.03 µm vs. 0.75 ± 0.07 µm; p < 0.01 compared with control. FMD was impaired in APS patients compared with control, 5.68% ± 0.42 vs. 8.29 ± 0.30, p < 0.01, respectively. IMT was significantly increased in APS patients compared with control, 0.52 ± 0.13 mm vs. 0.40 ± 0.06 mm, p < 0.01, respectively. Soluble TF, thiobarbituric acid-reactive substances levels were increased in the sera from APS patients compared with control. CONCLUSIONS: This preliminary study supports, for the first time, that in APS patients endothelial glycocalyx is impaired, which could lead to thrombosis, endothelial dysfunction and early atherosclerosis.

[Assessment of endothelial function in autoimmune diseases]. / Évaluation de la fonction endothéliale au cours des maladies auto-immunes.

Numerous autoimmune-inflammatory rheumatic diseases have been associated with accelerated atherosclerosis or other types of vasculopathy leading to an increase in cardiovascular disease incidence. In addition to traditional cardiovascular risk factors, endothelial dysfunction is an important early event in the pathogenesis of atherosclerosis, contributing to plaque initiation and progression. Endothelial dysfunction is characterized by a shift of the actions of the endothelium toward reduced vasodilation, a proinflammatory and a proadhesive state, and prothrombic properties. Therefore, assessment of endothelial dysfunction targets this vascular phenotype using several biological markers as indicators of endothelial dysfunction. Measurements of soluble adhesion molecules (ICAM-1, VCAM-1, E-selectin), pro-thrombotic factors (thrombomodulin, von Willebrand factor, plasminogen activator inhibitor-1) and inflammatory cytokines are most often performed. Regarding the functional assessment of the endothelium, the flow-mediated dilatation of conduit arteries is a non-invasive method widely used in pathophysiological and interventional studies. In this review, we will briefly review the most relevant information upon endothelial dysfunction mechanisms and explorations. We will summarize the similarities and differences in the biological and functional assessments of the endothelium in different autoimmune diseases.

Assessment of cardiac structure and left atrial appendage functions in primary antiphospholipid syndrome: a transesophageal echocardiographic study.

BACKGROUND AND PURPOSE: Although thromboembolic events are the major complication of primary antiphospholipid syndrome (PAPS), cardiac involvement is commonly present. Left atrial appendage (LAA) is recognized as an important source for thrombus formation and thromboembolism. The purpose of the study was to assess the structure and function of LAA with transesophageal echocardiography (TEE) in PAPS patients. METHODS: Thirty-one PAPS patients (22 women, mean age 36+/-9 years) in sinus rhythm and 31 (17 women, mean age 37+/-7 years) controls with normal TEE examination were investigated. RESULTS: Eighty-four percent of the PAPS patients had functional and structural valvular defect predominantly in the mitral valve. Valvular lesions were especially frequent in PAPS patients with a history of cerebrovascular events, patients with history of arterial thrombosis (91.6%), and patients with high titers of IgG anticardiolipin antibodies (100%). Intracardiac thrombus was present in 5 patients and in 1 of them it was located in LAA. The structure of LAA was similar between groups. Left atrial appendix ejection fraction (51.8+/-4 versus 48.6+/-5.5%; P<0.05) and LAA peak outflow velocity (87+/-10.9 versus 80.6+/-10.3 cm/s; P=0.02) was significantly higher in PAPS group compared with controls. In PAPS patients with mitral regurgitation (MR), LAA outflow peak velocity (84.3+/-10 versus 98.6+/-6.5 cm/s; P=0.002) and LAA inflow peak velocity (67.8+/-10.5 versus 80.8+/-8.6 cm/s; P=0.009) were significantly lower compared with PAPS patients without MR. CONCLUSIONS: It was concluded that disease process in PAPS frequently involved cardiac valves especially mitral valve but spared LAA function. LAA function was normal, but intracardiac thrombus was present in 5 patients and 1 of them was located in LAA. MR in PAPS patients seems to impair LAA function.

Hypercoagulability: clinical assessment and treatment.

This review emphasizes pathophysiology, clinical features, assessment, and therapy for hypercoagulability. Risk factors that further increase clotting include obesity, recent surgery, pregnancy, and cancer. Clinical examples of coagulation abnormalities may occur from single or multiple abnormalities and include both inherited and acquired defects. Laboratory testing undertaken at the time of acute thrombosis is often inaccurate or difficult to interpret. Individuals are best tested when they are not taking anticoagulants. Treatment of patients with either inherited or acquired abnormalities usually requires heparin compounds followed by warfarin, but the length of therapy has not yet been settled. Asymptomatic individuals with underlying hypercoagulability may not require treatment except in clot-promoting situations such as trauma, pregnancy, recent surgery, or use of venous access devices. The detection of one abnormality may no longer suffice because multiple defects can be found frequently. In patients with clotting and underlying risk factors, such as malignancy, pregnancy, estrogens, or surgery, an assessment for hypercoagulability should be considered.

M mode and Doppler echocardiographic assessment of left ventricular diastolic function in primary antiphospholipid syndrome.

BACKGROUND: High titres of serum antiphospholipid antibodies are a possible pathogenic factor for cardiac lesions in patients with systemic lupus erythematosus. OBJECTIVE: To test the hypothesis of a causal link between high titres of antiphospholipid antibodies in the serum and myocardial involvement in patients without systemic lupus erythematosus. PATIENTS AND DESIGN: 18 patients with primary antiphospholipid syndrome (recurrent fetal loss, arterial and/or venous thrombosis, high titres of antiphospholipid antibodies, and no criteria for systemic lupus erythematosus) were prospectively studied by cross sectional, M mode, and pulsed Doppler echocardiography, and compared with 18 healthy controls. The pulsed Doppler indices of left ventricular diastolic function included isovolumic relaxation time and four mitral outflow indices: peak velocity of early flow, peak velocity of late flow, early to late peak flow velocity ratio, and rate of deceleration of early flow. Four computerised M mode indices were also measured: peak rate of left ventricular enlargement in diastole, peak rate of posterior wall thinning, peak velocity of lengthening of the posterior wall, and velocity of circumferential chamber lengthening. RESULTS: Compared with controls, patients with primary antiphospholipid syndrome had higher values for isovolumic relaxation time and peak velocity of late mitral outflow and lower values for early to late mitral peak outflow velocity ratio, rate of deceleration of early mitral outflow, peak rate of left ventricular enlargement in diastole, peak rate of posterior wall thinning, peak velocity of lengthening of the posterior wall and velocity of circumferential chamber lengthening. CONCLUSION: This abnormal pattern reflects an impairment of myocardial relaxation and filling dynamics of the left ventricle in patients with primary antiphospholipid syndrome who were free of any clinically detectable heart disease. These data suggest that high serum titres of antiphospholipid antibodies may be associated with subclinical myocardial damage.