RESUMO
BACKGROUND: This investigation was designed to determine and compare the distribution pattern of anti-neutrophil cytoplasmic antibodies (ANCA) in patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) in the presence or absence of periodontal disease. METHODS: Sera of 30 patients with SLE and 30 with RA were tested for ANCA utilizing an indirect enzyme immunosorbent assay (ELISA) directed to a neutrophil granular extract and 6 neutrophil granule proteins. A control group of 20 healthy individuals showing neither evidence of periodontal disease nor systemic compromise was also included in this study. RESULTS: For RA, the number of ANCA-positive sera was very low but was evenly distributed among patients with and without periodontitis. Conversely, a high number of ANCA-positive sera in SLE was found mostly in individuals presenting periodontal compromise. A statistically significant association between ANCA and periodontitis in SLE patients was found (P <0.005, chi square test). CONCLUSIONS: A marked difference in the number and distribution of ANCA with respect to periodontitis between RA and SLE was found. Hyperresponsiveness of B cells and polyclonal B activation to periodontopathic bacteria in SLE might be accountable for the high numbers of ANCA and the close association observed between those autoantibodies and periodontitis in SLE.