Article Text

Download PDFPDF

PS2:23 Anti-c1q antibodies in turkish systemic lupus erythematosus patients
  1. S Tekeoglu,
  2. D Temiz Karadag,
  3. O Ozdemir Isik,
  4. A Yazici and
  5. A Cefle
  1. Kocaeli University, Internal Medicine, Rheumatology Department, Kocaeli, Turkey


Purpose Anti-C1q has been shown to be associated with systemic lupus erythematosus (SLE) and disease activity of lupus nephritis in previous studies. We studied anti-C1q specificity for SLE versus rheumatic disease controls and healthy controls and the association with SLE manifestations in a single centre cross-sectional study.

Methods Demographics, disease information and blood samples were obtained during routine follow-up visits of patients attending Kocaeli University rheumatology outpatient clinic. There were 150 SLE patients (92% female, mean: 46 years). Control group had 85 rheumatoid arthritis patients, 16 patients with other diseases (Sjogrens’s syndrome, systemic sclerosis, adult onset Still disease, psoriatic arthritis) and 49 healthy persons (88% female, mean: 45 years). Anti-C1q was measured by ELISA according to manufacturer’s instructions.

Results In SLE group 72 patients had renal, 10 patients had neurologic disease, 25 patients had antiphospholipid syndrome (APS). Anti-dsDNA was positive in 92 patients, anti-Sm was positive in 18 patients, 83 patients had low complement levels. Prevalence of anti-C1q was 5% (8/150) in patients with SLE and 1% (2/150) in controls (p=0.88). There was no correlation between clinics (renal, neurologic, hematologic, mucocutanous disease, arthritis, serositis, APS) or laboratory findings (Anti-dsDNA, anti-Sm, low complement levels, direct Cooms’ test). Within anti-C1q positive group 6 patients had renal disease, 4 had SLEDAI scores 4 or more. None of them had nervous system disease. Six patients had leukopenia, 2 had thrombocytopenia, 5 had mucocutanous disease. Laboratory findings were as follows; 6 patients had anti-dsDNA, 1 had anti-Sm antibody, 6 had low complement levels.

Conclusions Even though there were studies showing the relationship between anti-C1q antibodies and renal disease, it was shown that most of the patients with antibody positivity were Asian ethnicity and younger than 30 years of age. Furthermore anti-C1q antibody was related to disease activation and eliminated within 3 months of treatment. There were also different commercial products available with different cut-off levels. Meta-analysis have shown although anti-C1q antibodies are associated with lupus nephritis, the post-test probabilities are not sufficient to provide certainty of the presence or absence of history of disease.

Abstract PS2:23 Table 1

Association between clinics, serology and Anti-C1Q in SLE

  • SLE
  • Anti-C1Q
  • Lupus nephritis

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.