Anti–β₂‐glycoprotein I antibodies in pediatric systemic lupus erythematosus and antiphospholipid syndrome

Abstract

Objective To determine whether serum ␤ 2 -glycoprotein I antibody (anti-␤ 2 GPI) detection improves identification of pediatric subjects at risk for antiphospholipid syndrome (APS). Methods. Serum antiphospholipid antibodies (aPL) were identified by anticardiolipin enzyme-linked immunosorbent assay (ELISA), lupus anticoagulant assays, and syphilis screening in children with primary APS, systemic lupus erythematosus (SLE), or SLE plus APS. Anti-␤ 2 GPI level and isotype were determined by ␤ 2 GPI ELISA and correlated with clinical manifestations and other aPL assays. Results. One hundred-ten subjects under 22 years of age and of mixed ethnicity were evaluated. Fifty-seven had SLE (including 14 with APS), 25 had primary APS, 16 had SLE-like APS, 6 were healthy children with aPL detected incidentally, 4 had other rheumatic diseases and 2 had other conditions. Anti-␤ 2 GPI were detected in 48% of SLE subjects and did not improve aPL detection over standard tests. Anti-␤ 2 GPI were associated with stroke (P ‫؍‬ 0.014), but not with other APS manifestations, and were rarely detected in primary APS. Among subjects with APS manifesting as chronic thrombocytopenia, anti-␤ 2 GPI distinguished subjects with SLE from those with primary APS. Conclusions. With the exception of stroke, anti-␤ 2 GPI detection does not improve identification of pediatric APS over that of traditional aPL assays. Anti-␤ 2 GPI are rare in pediatric primary APS, but may predict evolution of chronic thrombocytopenia to SLE.

Predictive value of persistent versus transient antiphospholipid antibody subtypes for the risk of thrombotic events in pediatric patients with systemic lupus erythematosus

“…One pediatric study assessed LAs, ACLAs, and anti-␤2-GPI in a heterogeneous cohort of patients with SLE, SLE-like syndrome, primary antiphospholipid antibody syndrome, or APLA positivity. 39 The study did not find an association of any APLA subtype with TEs either in the total cohort or in the subgroup of children with SLE.…”

Antiphospholipid Syndrome in Pediatrics

“…The reported prevalence of aCL and LA in juvenile SLE ranges from 19% to 87% and from 10% to 62%, respectively ( Table 2) (reviewed in [39][40][41][42][43][44][45][46][47][48][49]). This wide variability may reflect either the different sensitivities and specificities of the assays used for the detection of aPL or a diversity in the clinical features of the patient populations.…”

Incidence and risk factors of thromboembolism in systemic lupus erythematosus: A comparison of three ethnic groups

“…These risk factors include age at SLE diagnosis (10,14,15), disease duration (10,14), hypertension (15)(16)(17), dyslipidemia (10,15,17,18), hyperhomocysteinemia (18,19), oxidized low-density lipoprotein (LDL) (18), smoking (14,16), use of corticosteroids and their duration (10,15,18), aPL (14,18,20,21), and valvular abnormalities of the heart (22). Other factors that may be relevant to arterial or venous thromboembolism in SLE are genetic mutations (23), pregnancy, and the use of exogenous estrogens (24) for contraception, climacteric symptoms, and control of cyclic SLE activity.…”