Autoantibodies predate the onset of Systemic Lupus Erythematosus in northern Sweden

• INTRODUCTION: Autoantibodies have a central role in systemic lupus erythematosus (SLE). The presence of autoantibodies preceding disease onset by years has been reported both in patients with SLE and those with rheumatoid arthritis, suggesting a gradual development of these diseases. To identify autoantibodies in a Northern European population predating the onset of symptoms of SLE and their relationship to presenting symptoms.METHODS: The register of patients fulfilling the American College of Rheumatology (ACR) criteria for SLE and with a given date for the onset of symptoms was co-analysed with the register of the Medical Biobank, Umea, Sweden. Thirty-eight patients were identified as having donated blood samples prior to symptom onset. A nested case-control study (1:4) was performed with 152 age- and sex-matched controls identified from within the Biobank register. Antibodies against anti- Sjogren's syndrome antigen A (Ro/SSA) (60 and 52 kDa), anti- Sjogren's syndrome antigen B (La/SSB), anti-Smith antibody (Sm), ribonucleoprotein (RNP), scleroderma-70 (Scl-70), anti- histidyl-tRNA synthetase antibody (Jo-1), double-stranded DNA (dsDNA); Centromere protein B and histones were analysed using the anti-nuclear antibody test II (ANA-II) Plus Test System (Athena Multi-Lyte(R)) on a Bio-Plex Array Reader (Luminex200). ANA were analysed using indirect immunofluorescence on Human Epidermal cells-2 (HEp2-cells) at a sample dilution of 1:100.RESULTS: Autoantibodies against nuclear antigens were detected 5.6 (+/- 4.7; mean +/- SD) years before the onset of symptoms and 8.7 (+/- 5.6) years before diagnosis in 63% of the individuals who subsequently developed SLE. The sensitivity (45.7%) was highest for ANA with a specificity of 95%, followed by anti-dsDNA and anti-Ro/SSA antibodies both with sensitivities of 20.0% at specificities of 98.7% and 97.4%, respectively. The odds ratio (OR) for anti-dsDNA predicting disease was 18.13 (CI 95%; 3.58-91.84), and for ANA 11.5 (CI 95%; 4.54-28.87). Anti-Ro/SSA antibodies appeared first, 6.6 (+/- 2.5) years prior to symptom onset. The mean number of autoantibodies in pre-diseased individuals was 1.4 and after disease onset 3.1 (P< 0.0005). The time predating disease was shorter, and the number of autoantibodies greater, in those individuals with serositis as a presenting symptom in comparison to those with arthritis and skin manifestations.CONCLUSIONS: Autoantibodies against nuclear antigens were detected in individuals developing SLE several years before the onset of symptoms and diagnosis. The most sensitive autoantibodies were ANA, Ro/SSA and dsDNA, with the highest predictive OR for anti-dsDNA antibodies. The first autoantibodies detected were anti-Ro/SSA.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Immunologi inom det medicinska området (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Immunology in the medical area (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Reumatologi och inflammation (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Rheumatology and Autoimmunity (hsv//eng)

Nyckelord

Clinical immunology

Klinisk immunologi

Rheumatology

Reumatologi

Clinical Immunology

klinisk immunologi

reumatologi

rheumatology

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