Childhood stroke and lupus anticoagulant

What is known about pediatric antiphospholipid syndrome?

INTRODUCTION

Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by vascular thrombosis and/or pregnancy morbidity associated with the persistent presence of antiphospholipid antibodies (aPL) including lupus anticoagulant (LA), anticardiolipin antibodies (aCL), and anti-β2 glycoprotein I antibodies (aβ2GPI).

AREAS COVERED

APS is considered as the most common acquired hypercoagulation state of autoimmune origin in children. Unfortunately, data about incidence, prevalence, thrombosis risk and effective treatment in paediatric APS are limited and unmethodical. Expert commentary: This review summarizes recent clinical, laboratory and therapy characterization of paediatric APS and emphasizes the differences between paediatric and adult populations.

Pediatric cerebellar stroke associated with elevated titer of antibodies to β2-glycoprotein

Antibodies to 2-glycoprotein I (anti-2GPI) have been associated with recurrent thrombosis and pregnancy morbidity. However, the prevalence of anti-2GPI in children suffering from cerebral and cerebellar infarction is unknown. We report on a 10-month-old boy who had an ischemic cerebellar stroke, secondary to antiphospholipid syndrome with high titers of immunoglobulin G anti-2GPI (first titer: 132U) anticardiolipin antibodies and lupus anticoagulant tests were negative. All other causes of infarction were excluded. To our knowledge, this is the first reported case of childhood cerebellar ischemic stroke with only anti-2GPI but no antibodies detectable in standard antiphospholipid assays.

Pediatric antiphospholipid syndrome

APS is rare in the pediatric age, but it represents an interesting phenomenon because most of the known "second hit" risk factors such as atherosclerosis, smoking, hypertension, contraceptive hormonal treatment, and pregnancy are not present in childhood. This could also be the reason for the prevalence of some clinical manifestations rather than others in PAPS. On the other hand, the increased frequency of infectious processes in the childhood age is likely responsible for the relatively high prevalence of non-pathogenic and transient aPL. Such points raise the problem of a different diagnosis or monitoring approach in pediatric APS. Of particular interest is the special entity of neonatal APS, which represents an in vivo model of acquired autoimmune disease, in which transplacentally acquired aPL cause thrombosis in the newborn. International registries for pediatric and neonatal APS are currently in place; epidemiologic, clinical, and laboratory re-search will help to shed light on all the still obscure aspects of this fascinating but rare disorder in the very young. Finally, treatment is less aggressive overall in pediatric APS, given the reluctance to anticoagulate children over the long term. Studies on the outcome of pediatric APS and the relative risks of prolonged anticoagulation in children are necessary to determine the type and duration of anticoagulation therapy.

Prothrombotic risk factors in ischemic stroke and migraine in children

OBJECTIVE

To evaluate the contribution of antiphospholipid antibodies (aPL) and thrombomodulin (Thm) in the pathogenesis of stroke and migraine in children.

MATERIALS AND METHODS

Ninety children were included in the study: 30 children (4-15 years) after an ischemic stroke of an unknown etiology; 30 migrainous patients (8-15 years), who were hospitalized in the Department of Developmental Neurology, Medical University of Gdansk, Poland, and 30 healthy children of the same age.

RESULTS

The statistical analysis showed an increase in the values of anticardiolipin antibodies (aCL), anti beta2-glycoprotein 1 (beta2-GP1) and Thm in children with stroke and migraine than in the control group. The resultant values were higher, but stayed at standard.

CONCLUSION

The possible role of prothrombotic factors in individual cases of pediatric stroke and migraine cannot be excluded.

Antiphospholipid syndrome in a child: an insight into the pathology, identification, and means of cure

Antiphospholipid syndrome (APS) has been well defined in adults; however, primary nontraumatic arterial thrombosis owing to this entity is unusual in the pediatric population. The authors report a case of APS with lower extremity arterial thrombosis who had discolored feet since delivery.

Neuronal-binding antibodies from patients with antiphospholipid syndrome induce cognitive deficits following intrathecal passive transfer

Antiphospholipid antibodies (aPL) have been suggested to play a role in causing cognitive and behavioral impairments. In the present study we investigated the pathogenic potential of aPL by intracerebro-ventricular (ICV) administration of immunoglobulins (IgG) from patients with antiphospholipid syndrome (APS). IgG, purified from the sera of four APS patients, was tested for binding to normal mouse brain by immunohistological staining. These IgG (7.5 microg) were injected ICV unilaterally to male C3H mice. Mice injected with IgG purified from pooled sera derived from healthy subjects served as controls. The mice were examined neurologically for motor function and coordination, and cognitively in a Morris water maze. The cognitive tests were performed with the experimenter blinded to the treatment. The performance of the mice in four separate experiments was compared by analysis of variance with repeated measures. IgG from one APS patient was found to bind best to neuronal structures in the hippocampus and cerebral cortex. Mice (n = 43) injected with this IgG performed worse in the water maze compared to the controls (n = 45) with significant effects of the aPL IgG on the overall performance of the mice (treatment, P < 0.03), on learning throughout the experiment (treatment x day, P < 0.02) and on short term memory (treatment x day xtrial, P < 0.002). IgG injected from two of the three other patients also bound specifically to mouse brain neurons and produced an impairment in performance of the water maze. These results support the hypothesis that aPL that gain access to the central nervous system may play a direct role in the pathogenesis of neurological manifestations of APS.

Anti-beta2-glycoprotein I antibodies and ischemic stroke in a 20-month-old boy

Antibodies to beta2-glycoprotein I (anti-beta2GPI) have been associated with recurrent thrombosis and pregnancy morbidity. However, the prevalence of anti-beta2GPI in children suffering from cerebral infarction is unknown. We report on a 20-month-old boy who had an ischemic stroke, secondary to antiphospholipid syndrome with high titers of immunoglobulin G anti-beta2GPI (first titer: 132 U; second titer 6 weeks later: 350 U; normal range: 0-100 U). Anticardiolipin antibodies and lupus anticoagulant tests were negative. All other causes of infarction were excluded. Laboratory studies showed anti-beta2GPI IgG levels of 164 U and 216 U at 6 months and 2 years, respectively, after the onset. The patient received treatment with low-dose aspirin. To our knowledge, this is the first reported case of childhood ischemic stroke with only anti-beta2GPI but no antibodies detectable in standard antiphospholipid assays. This case supports the recommendation of others to search for these antibodies in the presence of strong clinical suspicion of antiphospholipid syndrome, when anticardiolipin antibodies and lupus anticoagulant tests are negative.

Optic neuropathy in primary antiphospholipid syndrome in childhood

Neurologic symptoms associated with antiphospholipid antibodies in children include thrombotic events, unilateral movement disorders, or migraine. We present a 7-year-old girl with bilateral optic neuropathy, cerebral white-matter lesions, and antiphospholipid IgM that responded to prednisone and tended to relapse when it was stopped. Remission was obtained under maintenance corticosteroid therapy, and the antiphospholipid antibodies disappeared. This case suggests a role for antiphospholipid antibodies in the pathogenesis of optic neuropathy in childhood.

Antiphospholipid antibody syndrome in pediatric patients

The antiphospholipid antibody syndrome is characterized by the association between recurrent arterial or venous thrombosis and the presence of circulating antiphospholipid antibodies. Antiphospholipid antibody-related thrombosis seems to constitute a significant proportion of childhood thromboses. About one third of children suffering a thrombotic event have circulating antiphospholipid antibodies, and more than two thirds of children with idiopathic cerebral ischemia meet the criteria for the diagnosis of antiphospholipid antibody syndrome. Because the other risk factors for thrombosis commonly found in adults have no impact on the pediatric patient, the risk for thrombosis and thrombotic recurrences and the optimal anticoagulation therapy may differ from adults.

Clinical characteristics of antiphospholipid antibody syndrome in children

OBJECTIVE

To evaluate the clinical features and outcome of antiphospholipid syndrome (APS) in children.

STUDY DESIGN

Retrospective chart review of patients seen at the Children's Hospital of Philadelphia and Children's Seashore House Pediatric Rheumatology Center between 1988 and 1993.

RESULTS

Nine patients with ages ranging from 8 months to 17 years are presented. Clinical features of five patients with primary APS, described in detail, were digital ischemia, stroke, chorea, Addison disease, and pulmonary vaso-occlusive disease. The four children with secondary APS had systemic lupus erythematosus. Clinical features of these patients include livedo reticularis, deep venous thrombosis, and pulmonary hypertension. Antiphospholipid titers, results of coagulation studies, and serologic findings did not predict outcome.

CONCLUSION

APS in children has diverse clinical features similar to those in adults and should be considered in cases of unexplained vaso-occlusive disease.

Antiphospholipid antibody syndrome in childhood strokes

The significance of antiphospholipid antibodies was examined in patients with childhood strokes. Eight patients, aged 2-13 years, who presented with acute hemiplegia were studied. On the basis of magnetic resonance imaging, magnetic resonance angiography, single photon emission computed tomography, and cerebral angiographic findings, 3 children were diagnosed as having infarctions due to moyamoya disease, and the others as having idiopathic infarctions. Serologic studies revealed elevated anticardiolipin antibody (ACA) IgG in 3 of the 5 patients with idiopathic infarction; no such elevation was revealed in patients with moyamoya disease. Values for all other tests, including ACA IgM and lupus anticoagulant, were within normal limits or negative in all patients. ACA IgG, therefore, may be a more important causative agent of childhood strokes than was previously considered.