Anti-nucleosome antibodies as a disease activity marker in patients with systematic lupus erythematosus
Year: 2006
Type: dissertation
Study design: Observational Study
Abstract: The clinical aspect of measuring the level of anti-nucleosome antibodies in patients with \nsystemic lupus erythematosus (SLE) has been well established and it is claimed that their \npresence is associated with the disease activity. The overall aim of this study was to \nmeasure the level of anti-nucleosome· antibodies in the SLE patients, to determine the \nsensitivity as well as the specificity of these antibodies in the diagnosis of the disease. The \nevaluation of the relationship between the levels of anti-nucleosome antibodies, the disease \nactivity as well as and other markers (anti-dsDNA antibodies, C3, C4 and CRP) were also \ncompared and assessed. \nIn this cross sectional study, all patients were selected from Hospital Universiti Sains \nMalaysia (HUSM), who were either attending the medical specialist's clinic or have been \nadmitted to the medical wards. Ninety SLE patients, forty-five other connective tissue \ndiseases (e.g., rheumatoid arthritis, mixed connective tissue disease, scleroderma, \nRaynaud's syndrome and Sjogren's s~drome) and ninety normal controls were tested for \nanti-nucleosome antibodies by enzyme linked immunosorbent assay (ELISA), anti-dsDNA \nand ANA by Immunofluorescence (IF), C3, C4 and CRP by immunoturbidometry \ntechniques. SLE diseases activity was evaluated by using SLE-Disease Activity Index \n(SLEDAI) score. A patient is defined as having active SLE when SLEDAI score is more \nthan 5.0 \nOut of 90 SLE patients, anti-nucleosome antibodies were positive in 52% of patients, \nwhereas these antibodies were positive in 7% of patients with other connective tissue \ndiseases. The median concentration of anti-nucleosome antibodies was significantly \ndifferent between SLE patients and other connective tissue diseases. None of the normal \ncontrols was found to be positive for these antibodies. Anti-dsDNA antibodies were \npositive in 3 7% SLE patients, whereas these antibodies were positive in 8% of patients with \nother connective tissue diseases. None of the normal controls was found to be positive for \nthese antibodies. ANA was found to be positive in 81% SLE patients, in 61% of patients \nwith other connective tissue diseases and 7% in normal controls. Anti-nucleosome \nantibodies had a sensitivity of 52%, whereas anti-dsDNA antibodies had a sensitivity of \n37%. The specificity of anti-nucleosome and anti-dsDNA antibodies was 98% and 97% \nrespectively. ANA had sensitivity and specificity of 81% and 75% respectively. Antinucleosome \nantibodies were positive in 98% of patients with active SLE, whereas these \nantibodies were positive in 14% of patients with inactive SLE. The median concentration of \nanti-nucleosome antibodies was significantly different between active and inactive SLE \npatients. Anti-dsDNA antibodies were found to be positive in 61% of patients with active \nSLE and in 16% of patients with inactive SLE. Anti-nucleosome antibodies had a stronger \ncorrelation than anti-dsDNA antibodies with SLEDAI score. The median concentration of \nC3 and C4 was significantly different between active and inactive SLE patients, and \nshowed an inverse and significant correlation with SLEDAI score, whereas the median \nconcentration of CRP was not significantly different between active and inactive SLE. \nIn conclusion, anti-nucleosome antibodies test is a recently developed test that may help in \ndiagnosis of SLE patients. Anti-nucleosome antibodies are highly sensitive and specific for \nthe diagnosis of SLE, especially when the anti-dsDNA antibodies are absent. Thus antinucleosome \nantibodies test can be a better tool for the diagnosis of SLE. Anti-nucleosome \nantibodies have a stronger and significant correlation with SLEDAI score than other \ntraditional disease activity markers. Therefore, it can be a useful and additional disease \nactivity marker to other laboratory tests that can help in the assessment SLE disease \nactivity.
Author: Ha, Suliman Tayseer
Language: English
Subfield: Rheumatology
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W7094612524