The frequency of autoantibodies in Turkish patients with lupus nephritis

We analysed the frequency of autoantibodies in 44 patients with lupus nephritis. Antinuclear antibody (ANA) was found in 91% of patients by an indirect immunofluorescence technique on HEp-2 cells at the time of study. Anti-dsDNA antibodies were found at high levels in most of the patients using the SynELISA test, which reveals both high and low avidity antibodies, but only in 64% of patients using the DAKO assay, which reveals high avidity antibodies. Anti-histone antibodies were found in 52% of the patients. Anti-SSA/Ro antibodies were positive in 27% of all patients; these patients also had prominent cutaneous involvement and photosensitivity. The frequency of anti-SSB/La and Anti-Sm antibodies was 7%. Immunoblotting experiments confirmed the findings shown by the techniques described above, and anti-ribosomal antibodies were found to be positive in more cases by the latter assay. IgA rheumatoid factor (RF) was more frequent (20.4%) than IgM RF (9.9%). In conclusion, Turkish patients suffering from lupus nephritis seem to express a total autoantibody profile similar to that reported for systemic lupus erythematosus from other parts of Europe.