Antinuclear antibodies measured by enzyme immunoassay in patients with systemic lupus erythematosus: relation to disease activity

Rheumatol Int. 2007 Aug;27(10):941-5. doi: 10.1007/s00296-007-0324-7. Epub 2007 Feb 16.


To evaluate the correlation between measurements of antinuclear antibodies serum levels by enzyme immunoassay (ANA-EIA), and the degree of systemic lupus erythematosus disease activity. To retest the performance of the test compared to measurement of antinuclear antibodies by immunofluorescence (ANA-IIF). Eighty-five sera from 71 patients with SLE were tested. Demographic, clinical, laboratory, and SLEDAI status were collected. The sera were tested for ANA-EIA and by ANA-IIF at 1:40 and 1:160 dilutions. Serum levels of ANA-EIA were compared to the overall SLEDAI score and to each of its components. A SLEDAI score of > or =6 was considered clinically significant. The sera of fifty-one healthy volunteers served as controls. Serum levels of ANA-EIA were significantly higher in patients with a SLEDAI score of > or =6 compared to the group of patients with a SLEDAI score of <6 (P = 0.004). High serum levels of ANA-EIA correlated significantly with elevated anti DS-DNA antibodies (P < 0.001), low C(3) or C(4) levels (P < 0.001), pyuria (P < 0.011), arthritis (P = 0.019), and new rash (P = 0.019). Levels of ANA-EIA were significantly higher in patients tested positive by IIF compared to those who tested negative. Higher serum levels of ANA-EIA correlated with clinically significant disease activity in patients with SLE. Higher serum levels of ANA-EIA also correlated with some single items of the SLEDAI. The results also reiterated the validity of ANA-EIA testing in patients with SLE. Further longitudinal studies are needed in order to test the hypothesis that serum ANA-EIA levels might reflect fluctuations in disease activity.

Publication types

  • Validation Study

MeSH terms

  • Adult
  • Antibodies, Antinuclear / blood*
  • Biomarkers / blood
  • Case-Control Studies
  • Cohort Studies
  • Female
  • Humans
  • Immunoenzyme Techniques / methods*
  • Lupus Erythematosus, Systemic / blood
  • Lupus Erythematosus, Systemic / immunology
  • Lupus Erythematosus, Systemic / physiopathology*
  • Male
  • Middle Aged
  • Predictive Value of Tests
  • Severity of Illness Index


  • Antibodies, Antinuclear
  • Biomarkers