Spectrum of clinical manifestations of antiphospholipid antibodies in childhood and adolescence

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.

Primary antiphospholipid syndrome presenting with a branch retinal artery occlusion in a 15-year-old boy

Acute vascular events are rare in the pediatric population, but there is an association with the presence of antiphospholipid antibodies. When there is no other underlying medical disorder, this is referred to as primary antiphospholipid syndrome. We present a case of a 15-year-old boy who developed an acute superior branch retinal artery occlusion. Complete evaluation revealed significant elevations in antiphospholipid antibodies. To our knowledge, there are no cases in children of primary antiphospholipid syndrome presenting with this clinical manifestation.

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.

Clinical significance of lupus anticoagulants in children

OBJECTIVES

To determine the spectrum of associated clinical manifestations and time course of lupus anticoagulants (LA) in children.

STUDY DESIGN

Retrospective study of 95 consecutive children (46 boys and 47 girls), with a median age of 5.3 years (range, 1.7 to 17.1 years), diagnosed with presence of LA at a hemostasis referral center; 83 were followed up over a median of 2.9 years (range, 6 weeks to 21.6 years).

RESULTS

At diagnosis, 80 of 95 (84%) children were free of symptoms, and presence of LA was found incidentally. Nine children (10%) had bleeding symptoms, 5 (5%) had thrombotic events, and 1 had systemic lupus erythematosus. Among the patients with bleeding, 5 had transient severe hypoprothrombinemia after adenovirus infections, and 3 had thrombocytopenia. None of the children who were initially free of symptoms had bleeding, thrombotic complications, or autoimmune disease subsequently. At follow-up, 48 of 83 (58%) patients had normal activated partial thromboplastin time values after 1.9 years (5 weeks to 19.1 years). Thirty-two (38%) still had activated partial thromboplastin time elevations but did not fulfill all criteria for presence of LA after 3.2 years (7.4 months to 9.3 years). Three (4%) patients, who had presented with thrombosis, had persistent positive LA, anti-cardiolipin, and antinuclear antibodies after 1.4, 2.8, and 7.5 years, respectively. One of these had recurrent thrombosis.

CONCLUSIONS

In most children the presence of LA did not lead to clinical complications and was transient. Bleeding occurred with additional hypoprothrombinemia or thrombocytopenia. Thrombosis was rare and strongly associated with persistently positive LA.

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.