title: Anti-nucleosome antibodies in patients with systemic lupus erythematosus: potential utility as a diagnostic tool and disease activity marker and its comparison with anti-dsDNA antibody.
abstract: OBJECTIVE
  To compare the utility of anti-nucleosome antibodies and anti-dsDNA antibodies in diagnosis of Systemic Lupus Erythematosus (SLE) and as a marker of disease activity.
  
  
  METHODS
  This is a hospital based observational study among 40 (37 females and 3 males) selected cases of SLE (> or = 4 ACR criteria) and 80 control. 40 cases of other systemic autoimmune disease (SAD) [e g. 29 cases of Rheumatoid arthritis, 4 cases of Systemic sclerosis/scleroderma, 4 cases of Sjögren syndrome, 3 cases of MCTD and 40 Healthy blood were taken as control. From each patient venous blood samples were collected and submitted for anti-nucleosome and anti-dsDNA antibodies assay by enzyme linked immunosorbent assay (ELISA).
  
  
  RESULTS
  Anti-nucleosome antibodies were positive in 19 (47.5%) SLE, 02 (05%) other SAD and none of the healthy persons. Anti dsDNA antibodies were positive in 15 (37.5%) SLE patients, 07 (17.5%) other SAD and 01(2.5%) healthy persons. For diagnosis of SLE, sensitivity of anti-ds DNA and anti-nucleosome antibody was found to be 37.5% and 47.50% respectively. The specificity of anti-nucleosome was 100% and that of anti-dsDNA was 97.50%. So, anti-nucleosome antibody test is more specific and more sensitive for diagnosis of SLE than anti-dsDNA. When SLE cases were compared with SAD, sensitivity of anti-dsDNA and anti-nucleosome antibody, for diagnosis of SLE, found to be 37.50% and 47.50% respectively but the specificity of anti-nucleosome was 95% and that of anti-dsDNA was 82.50%. Both antibodies show positive correlation with SLEDAI score .The correlation coefficient was stronger for anti-dsDNA antibodies (r = +0.550, P = < .001) than anti-nucleosome antibodies (r = +0.332, P = < .05) CONCLUSIONS: Anti-nucleosome antibodies show higher positivity than anti-dsDNA antibodies among SLE than other SAD and healthy population. Anti-nucleosome antibodies are more sensitive and specific for the diagnosis of SLE than anti-dsDNA antibodies. Anti-nucleosome and anti-dsDNA both show positive correlation with SLEDAI. But anti-dsDNA antibodies show stronger correlation with SLEDAI than anti-nucleosome. So, anti-nucleosome antibodies can be used as an additional marker for diagnosis of SLE and SLE disease activity.
authors.forename: Renu
authors.initials: R
authors.lastname: Saigal
authors.forename: Laxmi Kant
authors.initials: LK
authors.lastname: Goyal
authors.forename: Abhishek
authors.initials: A
authors.lastname: Agrawal
authors.forename: Archna
authors.initials: A
authors.lastname: Mehta
authors.forename: Pradeep
authors.initials: P
authors.lastname: Mittal
authors.forename: R N
authors.initials: RN
authors.lastname: Yadav
authors.forename: P D
authors.initials: PD
authors.lastname: Meena
authors.forename: Dilip
authors.initials: D
authors.lastname: Wadhvani
mesh_terms: D000293:Adolescent; D000328:Adult; D000974:Antibodies, Antinuclear / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D002648:Child; D004247:DNA / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009707:Nucleosomes / Q000276:immunology; D011237:Predictive Value of Tests
chemical_list: D000974:Antibodies, Antinuclear; D015415:Biomarkers; D009707:Nucleosomes; D004247:DNA