title: Anti-beta2-glycoprotein I antibodies in pediatric systemic lupus erythematosus and antiphospholipid syndrome.
abstract: OBJECTIVE
  To determine whether serum beta2-glycoprotein I antibody (anti-beta2GPI) 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-beta2GPI level and isotype were determined by beta2GPI 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-beta2GPI were detected in 48% of SLE subjects and did not improve aPL detection over standard tests. Anti-beta2GPI 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-beta(2)GPI distinguished subjects with SLE from those with primary APS.
  
  
  CONCLUSIONS
  With the exception of stroke, anti-beta2GPI detection does not improve identification of pediatric APS over that of traditional aPL assays. Anti-beta2GPI are rare in pediatric primary APS, but may predict evolution of chronic thrombocytopenia to SLE.
authors.affiliation: Pediatric Rheumatology, University of California at San Francisco, 94143, USA. scheven@itsa.ucsf.edu
authors.forename: Emily
authors.initials: E
authors.lastname: von Scheven
authors.forename: David V
authors.initials: DV
authors.lastname: Glidden
authors.forename: Melissa E
authors.initials: ME
authors.lastname: Elder
mesh_terms: D000293:Adolescent; D000328:Adult; D017153:Antibodies, Anticardiolipin / Q000276:immunology; D016736:Antiphospholipid Syndrome / Q000150:complications / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006023:Glycoproteins / Q000276:immunology*; D006801:Humans; D007223:Infant; D008180:Lupus Erythematosus, Systemic / Q000150:complications / Q000276:immunology*; D008297:Male; D008403:Mass Screening / Q000379:methods; D011655:Pulmonary Embolism / Q000209:etiology / Q000276:immunology; D020246:Venous Thrombosis / Q000209:etiology / Q000276:immunology; D053482:beta 2-Glycoprotein I
chemical_list: D017153:Antibodies, Anticardiolipin; D006023:Glycoproteins; D053482:beta 2-Glycoprotein I