title: Measurement of autoantibodies in pediatric-onset systemic lupus erythematosus and their relationship with disease-associated manifestations.
abstract: OBJECTIVE
  To evaluate an autoantibody profile in pediatric-onset systemic lupus erythematosus (SLE) patients to determine clinical and statistical associations with disease-associated manifestations.
  
  
  METHODS
  Sera from 53 SLE patients and 22 healthy individuals were collected. Antibodies to C1q, histone, chromatin, ribosomal P, dsDNA, and high-avidity dsDNA were measured by enzyme-linked immunosorbent assays. Patient records were evaluated for clinical and laboratory associations.
  
  
  RESULTS
  The most prevalent autoantibodies found in the SLE cohort were anti-C1q antibodies (n = 32, 60%), which correlated significantly with proteinuria and decreased complement levels (P < 0.05). Anti-C1q and antihistone antibodies were significantly elevated in patients with class III/IV nephritis compared with class I/II/V nephritis (P = 0.041). SLE patients with active nephritis at the time of sample collection demonstrated significantly elevated levels of anti-C1q antibodies compared with those without active nephritis, also exhibiting 100% sensitivity for active nephritis, proteinuria, and urinary casts. Antibodies to C1q, dsDNA, histone, and chromatin were significantly elevated in patients with active disease (P < 0.01). Chart-documented anti-dsDNA antibodies were positive in 28 SLE patients, INOVA anti-dsDNA antibodies in 25 patients, and high-avidity anti-dsDNA antibodies in 8 patients. Antihistone correlated significantly with leukopenia and hemolytic anemia (P < 0.05).
  
  
  CONCLUSIONS
  This study indicates the importance of measuring anti-C1q antibodies in pediatric-onset SLE patients because elevated anti-C1q antibodies may be more indicative of renal disease activity, showing significant correlation with proteinuria, urinary casts, and active nephritis. Antibodies to C1q, histone, chromatin, and dsDNA exhibited the strongest association with clinical features, indicating the importance of measuring all of these antibodies in pediatric-onset SLE patients.
authors.affiliation: Division of Adult and Pediatric Rheumatology, St. Louis University School of Medicine, St. Louis, MO 63104, USA.
authors.forename: Brooke E
authors.initials: BE
authors.lastname: Gilliam
authors.forename: Amanda K
authors.initials: AK
authors.lastname: Ombrello
authors.forename: Rufus W
authors.initials: RW
authors.lastname: Burlingame
authors.forename: Peri H
authors.initials: PH
authors.lastname: Pepmueller
authors.forename: Terry L
authors.initials: TL
authors.lastname: Moore
mesh_terms: D000293:Adolescent; D000328:Adult; D001323:Autoantibodies / Q000097:blood*; D002648:Child; D015922:Complement C1q / Q000276:immunology*; D005260:Female; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology*; D008297:Male; D012720:Severity of Illness Index
chemical_list: D001323:Autoantibodies; D015922:Complement C1q