Atypical presentation of pediatric antiphospholipid syndrome

Abstract

APS: antiphospholipid syndrome DRVVT: dilute Russell viper venom time EAH: eccrine angiomatous hamartoma LR: livedo reticularis SLE: systemic lupus erythematosus INTRODUCTION Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by potentially life-threatening recurrent vascular thrombosis, miscarriage, and the presence of antiphospholipid antibodies, including anti-cardiolipin, anti-beta 2 glycoprotein, and lupus anticoagulant. It is additionally associated with false-positive rapid plasma reagin titer. APS can either be primary, presenting in the absence of another autoimmune disorder, or secondary, presenting with another autoimmune disorder. Data on the epidemiology of APS are limited, but 1 study found the annual incidence and prevalence to be 2.1 and 50 per 100,000, respectively. The epidemiology of APS is further limited in pediatric patients, as it is likely underdiagnosed due to a lack of pediatric-specific clinical criteria. Interestingly, children may have a higher rate of progression from primary to secondary APS. Cutaneous manifestations are common in APS, arising in 18% of cases, including livedo reticularis (LR), Raynaud phenomenon, atrophie blanche, anetoderma, urticaria, malignant atrophic papulosis, purpura fulminans, ulcerative skin lesions, pseudovasculitic lesions, and reactive angioendotheliomatosis. Although APS has been associated with various skin conditions, it has no established association with eccrine angiomatous hamartomas (EAHs). EAHs are rare, benign, acquired, or congenital neoplasms of eccrine and angiomatous structures, often within the middle or deep dermis, that usually present on the distal extremities with varied clinical features, including