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

Preparation and evaluation of oral enteric sustained-release liquid formulations of aspirin

AIM

To develop an enteric sustained-release nanoparticle formulations of aspirin for applicability to a broader population.

METHODS

Aspirin-loaded nanoparticles were prepared using poly(lactic-co-glycolic acid) (PLGA) and the enteric polymer Eudragit L100-55 through an optimized oil-in-water emulsification solvent evaporation method. The nanoparticles were subjected to comprehensive physicochemical characterization, including particle size, zeta potential, and morphological analysis. Additionally, their stability, in vitro drug release profile, cytotoxicity, intestinal absorption, and in vivo pharmacokinetics were systematically evaluated.

RESULTS

The nanoparticles exhibited well-defined spherical morphology, uniform particle size, and favorable surface charge, demonstrating excellent biocompatibility. In the in vitro drug release study, AS-PLGA@NPs exhibited pronounced enterolysis effect. The morphology of the nanoparticles was confirmed by scanning electron microscopy (SEM) at different release stages. In vivo intestinal absorption and pharmacokinetic studies in rats demonstrated that AS-PLGA-EL@NPs enhanced drug absorption, prolonged drug release, and showed higher bioavailability compared to conventional enteric-coated tablets.

CONCLUSION

The development and preparation of an oral enteric sustained-release nanoparticle delivery system for aspirin has the potential to serve a broader population, with promising applications in various therapeutic contexts.

Pediatric antiphospholipid syndrome: expanding our understanding of antiphospholipid syndrome in children

PURPOSE OF REVIEW

Antiphospholipid syndrome (APS) is an autoimmune, thromboinflammatory disease, which affects children and adults. There are particular features of the disease and nuances to diagnosis and management in a pediatric population, which must be appreciated to improve clinical care.

RECENT FINDINGS

Pediatric-specific epidemiological studies highlight that pediatric APS is quite rare with incidence in some populations of 0.2 per 100 000. There are new classification criteria in APS, which include a wider range of clinical features increasingly identified in registry data and case series of pediatric APS, though validation in pediatric APS is still needed. There is a particularly high proportion of pediatric APS patients with noncriteria antiphospholipid antibodies (aPL). Recurrent thrombosis is especially common in pediatric APS, highlighting the difficulty of management of this disease with high morbidity in children.

SUMMARY

Recent research has enhanced understanding of pediatric-specific APS epidemiology, laboratory findings, the wide variety of clinical features, and challenges in successful treatment. Future directions could include evaluation of potentially unique features in pediatric pathophysiology, an evaluation of the new APS classification criteria in children, broader prospective data on clinical and laboratory features, and a continued search for treatment beyond committing young patients to lifelong anticoagulation.

Mechanical thrombectomy in a pediatric patient with antiphospholipid syndrome-a case report

Stroke ranks among the top 10 most common causes of death in children. Recently, there has been a significant increase in the number of strokes in the pediatric population. Mechanical thrombectomy is an uncommon method for treating acute ischemic stroke (AIS) in children. This case report discusses a 13-year-old girl with a history of ischemic stroke for the past 3 months, obesity, hypertension, and antiphospholipid syndrome (APS, treated with rivaroxaban), who suffered another ischemic stroke and underwent mechanical thrombectomy with favorable clinical outcomes. Additionally, the patient was diagnosed with antithrombin III deficiency. It is necessary to identify risk factors for AIS in the pediatric population, such as thrombophilia or autoimmune diseases, such as antiphospholipid syndrome, and to develop guidelines for the use of thrombectomy in children. This method could reduce mortality, improve quality of life, prevent disability, and lower future medical costs.

Antiphospholipid syndrome presenting as isolated renal vein thrombosis: a case report and review of the literature

BACKGROUND

Pediatric antiphospholipid syndrome is a rare systemic autoimmune disorder characterized by recurrent thrombotic events in the presence of antiphospholipid antibodies. Isolated right renal vein thrombosis resulting in a nonfunctional kidney is an uncommon manifestation of antiphospholipid syndrome. Here, we present our experience with antiphospholipid syndrome secondary to systemic lupus erythematosus.

CASE PRESENTATION

A 10 year-old girl from a Hindu family in Sindh, Pakistan, who had previously been healthy, presented in 2020 with a 1-week history of abdominal pain, gross hematuria, vomiting, and fever. On examination, she was anxious, febrile, hypertensive, and had an enlarged, tender right kidney. Other systemic examinations, including skin, locomotor, respiratory, cardiovascular, and nervous systems, were unremarkable. Initial investigations for ureteric colic and acute pyelonephritis were negative, but revealed thrombocytopenia on complete blood count, mild proteinuria, hematuria on urinalysis, and normal kidney and liver function tests, along with normal prothrombin and activated partial thromboplastin times. An abdominal ultrasound showed a diffusely enlarged, echogenic right kidney with a loss of corticomedullary distinction and cortical hypoechoic areas, while the left kidney appeared normal. Color Doppler ultrasound identified a large thrombus in the right renal vein, completely obstructing its lumen and showing no blood flow. The thrombus extended into the inferior vena cava. Computed tomography angiography confirmed an organized thrombus completely blocking the right renal vein and extending into the infrahepatic portion of the inferior vena cava. No prothrombotic risk factors were identified during clinical evaluation, and thrombophilia screening was negative. However, lupus serology and antiphospholipid antibodies were positive, confirming a diagnosis of secondary antiphospholipid syndrome.

MANAGEMENT AND OUTCOME

The patient was treated with enoxaparin anticoagulation, later transitioned to warfarin sodium, and her hypertension was managed with captopril and amlodipine. She showed gradual improvement over 10-12 days and was discharged on anticoagulants, antihypertensive medications, antiplatelet agents, and hydroxychloroquine. A follow-up Doppler ultrasound revealed persistent blockage of the right renal vein by the thrombus, with no thrombus in the inferior vena cava. A dimercaptosuccinic acid scan indicated a nonfunctioning right kidney. While nephrectomy was recommended, her parents declined the procedure. Anticoagulation therapy was switched to rivaroxaban to avoid frequent international normalized ratio monitoring. Her captopril was replaced after control of blood pressure with losartan. Over the next 4 years, her follow-up was uneventful. She demonstrated normal growth, stable blood pressure (off antihypertensive), and normal kidney function without proteinuria. There were no lupus flares or thrombotic recurrences. Her most recent urinalysis was normal, with a serum creatinine level of 0.6 mg/dL and an estimated glomerular filtration rate > 170 mL/min/1.73 m2.

CONCLUSION

Isolated renal vein thrombosis is a rare presentation of antiphospholipid syndrome and poses a diagnostic challenge in the absence of preexisting prothrombotic risk factors. Early diagnosis and timely management are crucial to prevent organ damage. In this case, the patient retained a solitary functioning kidney. Long-term follow-up is essential to monitor for lupus flares, thrombus recurrence, hypertension, proteinuria, and progression to chronic kidney disease, as well as to ensure continued thromboprophylaxis.

Bilateral medial medullary and spinal cord infarctions presenting as locked-in syndrome in an adolescent with primary antiphospholipid syndrome

Bilateral medial medullary infarction (BMMI) is a rare stroke subtype in the paediatric population characterised by quadriplegia, cranial nerve dysfunction and respiratory failure. MRI typically reveals a 'heart-shaped' sign in the medial medulla on diffusion-weighted imaging (DWI). Paediatric stroke aetiologies, including vasculopathy, thrombophilia and cardioembolic disease, differ from those in adults. Antiphospholipid syndrome (APS) is a rare but important cause of paediatric stroke.We report an adolescent male presenting with acute quadriplegia, bulbar dysfunction and respiratory failure with intact cognition, consistent with locked-in syndrome. MRI confirmed BMMI with concurrent spinal cord infarction, and APS was diagnosed based on persistently elevated anticardiolipin antibodies. Anticoagulation therapy and rehabilitation were initiated. However, minimal neurological improvement was observed at 1-year follow-up. This case highlights the rarity of BMMI in children and underscores the importance of early diagnosis and management as well as the recognition of uncommon causes such as APS.

Thrombotic Disorders in the Newborn

The coagulation and thrombotic systems of an infant are fundamentally different from those of adults and older children. Hemostatic factors have inherently lower circulation levels in infants and are also affected prenatally by conditions of pregnancy. The unique physiology of neonates can contribute to a procoagulant state, which can result in a high level of morbidity and mortality. This review outlines the epidemiology, clinical characteristics, diagnosis and management, and etiologies of congenital and acquired forms of thrombotic disorders, with a discussion of the evaluation for hypercoagulation.

Updates in diagnosis and treatment of pediatric antiphospholipid syndrome

PURPOSE OF REVIEW

This review offers an overview of the most important recent articles on pediatric APS.

RECENT FINDINGS

Non-thrombotic extra criteria manifestations were prevalent in pediatric APS. Pregnancy morbidity has been described as the first manifestation of APS at youth age, impairing gestational outcomes. The 2023 APS criteria were developed for adult APS patients, and there is still a lack of pediatric-specific APS criteria. Catastrophic APS was more commonly reported as the initial manifestation of pediatric APS than in adults. Regarding treatment, direct oral anticoagulants have been recently approval for pediatric patients with venous thrombosis. New approaches have been proposed for severe cases, for arterial thrombosis, and rituximab for refractory cases. Recurrences typically occurred early and were associated with older age at diagnosis. Current studies highlighted the multifaceted nature of pediatric APS. Further large prospective multicenter studies evaluating new medications capable of reducing recurrence risk and improving prognosis in this population will be required.

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

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

Primary catastrophic antiphospholipid syndrome in children with midbrain infarction: a case report

Background

Catastrophic antiphospholipid syndrome (CAPS) is a multi-system autoimmune disease characterized by extensive thrombosis. Pediatric CAPS is extremely rare and associated with a high mortality rate, especially when midbrain infarction is involved. Hence, early diagnosis and prompt initiation of appropriate treatment for CAPS complicated by midbrain infarction are of utmost importance in achieving favorable outcomes.

Case presentation

In this report, we present the case of a 14-year-old girl who presented with neurological symptoms and digestive system infection and was initially diagnosed with an "intracranial infection". After a series of rigorous diagnostic procedures, the patient was ultimately diagnosed with primary CAPS and was immediately transferred to the intensive care unit where she was treated with anticoagulation, glucocorticoids, intravenous immunoglobulin (IVIG) therapy, and multiple plasma infusions. Twenty-seven days after admission, the patient's condition improved with standardized treatment, and she was discharged and followed up regularly.

Conclusion

This case report provides a description of the clinical features observed in a pediatric patient with CAPS and concurrent midbrain infarction, highlighting the crucial role of early diagnosis and timely treatment in influencing patient prognosis.

Epidemiology of thromboembolic events in children and adolescents with antiphospholipid syndrome: A systematic review with meta-analysis

BACKGROUND AND AIM

This was a systematic review and meta-analysis of the prevalence of thromboembolic events in children and adolescents with antiphospholipid syndrome (APS).

METHODS

We searched PubMed, EMBASE and Web of Science to select relevant articles published between 1 January 2000 and 27 February 2022. We used the random-effects meta-analysis to estimate pooled point prevalence rates of thromboembolic events in studies with a minimum sample size of 30.

RESULTS

We included five studies reporting data of 336 children and adolescents with primary APS and secondary APS (SAPS). Pooled point prevalence rates of initial general thrombosis, arterial thrombosis, venous thrombosis and stroke in individuals with seropositive APS were 98.2% (95% confidence interval [CI] 87.5-100), 27.6% (95% CI 21.4-34.2), 51.1% (95% CI 38.2-63.9) and 13.4% 95% CI (6.3-22.7), respectively. Pooled point prevalence rates of initial arterial and venous thromboses in children and adolescents with SAPS were 45.7% (95% CI 21.1-71.6) and 29.2% (95% CI 14.8-46), respectively.

CONCLUSION

Arterio-venous thromboembolism is highly frequent in children and adolescents with SAPS. More studies using thrombotic and non-thrombotic APS classification criteria are warranted to better assess the frequency and predictors of thromboembolism in age- and ancestry-diverse pediatric populations affected by different types of APS.

Case Report: In situ pulmonary artery thrombosis in a 12-year-old girl classified as systemic lupus erythematosus

In situ pulmonary artery thrombosis (ISPAT) is a relatively rare but potentially life-threatening complication of systemic lupus erythematosus (SLE) in children. We report the case of a 12-year-old girl who presented with fever, chest pain, and dyspnea. Immune thrombocytopenia was identified due to purpura and menorrhagia 3 months before presentation with a lowest platelet count of 12 × 109/L. The sudden onset of fever, chest pain, and dyspnea were misdiagnosed as hyperinflammatory responses caused by pneumonia; these symptoms ameliorated with glucocorticoid and antibiotic treatment. The reappearance of symptoms after dose reduction of glucocorticoids and the observation of bloody bronchoalveolar lavage fluid necessitated further evaluation. Pulmonary artery thrombosis/embolism was identified using computed tomography pulmonary angiography and high D-dimer quantitative level of 4,118 μg/L (normal <252 μg/L). Ultrasonography of the deep and superficial veins of both lower limbs and renal veins revealed no thrombosis, suggesting the diagnosis of ISPAT. Further etiological evaluation revealed positive antinuclear antibodies, lupus anticoagulant, and anti-SSA antibodies, confirming SLE. Repeated normal urine analysis indicated that lupus nephritis was unlikely. Further, the negative anticardiolipin and anti-β2 glycoprotein antibodies and temporary positive lupus anticoagulant suggested that antiphospholipid syndrome was unlikely. The patient received anticoagulants, glucocorticoids, hydroxychloroquine, and mycophenolate therapy. Her symptoms gradually improved, and she was discharged. At the 1-month follow-up, the thrombosis had resolved. During the 1-year follow-up, her condition remained well without SLE relapse. Our experience with this case emphasizes searching for SLE in the case of ISPAT and pulmonary hemorrhages. ISPAT can occur in children with SLE and may be caused by hyperinflammatory response during SLE flare.

Pediatric Antiphospholipid Syndrome Presenting as a Massive Stroke: A Case Report

Pediatric strokes are infrequent yet impactful occurrences with distinct challenges due to their unique pathophysiology and diagnostic complexities. Antiphospholipid syndrome, an autoimmune disorder characterized by antiphospholipid antibodies, can lead to prothrombotic states causing vascular occlusions. Here, we present the case of a previously healthy two-year-old girl who presented with sudden right-sided hemiparesis and altered consciousness. Comprehensive assessments and evaluations revealed a diagnosis of a massive left middle cerebral artery ischemic stroke secondary to antiphospholipid syndrome. The patient received intensive care, antiplatelet therapy, and supportive measures. Gradual improvement in neurological status and motor skills was observed during hospitalization, and the patient underwent comprehensive rehabilitation. This case emphasizes the importance of vigilance, thorough diagnostic evaluation, and tailored treatment strategies. Anticoagulation therapy plays a pivotal role, necessitating a delicate balance between thrombosis prevention and bleeding risk. The significance of multidisciplinary approaches and specialized care for pediatric stroke cases is underscored.