Antinuclear Autoantibodies in Patients with Inflammatory Bowel Disease (High Prevalence in First-Degree Relatives)

Crohn's disease and ulcerative colitis show afamilial aggregation. The role of antinuclearautoantibodies, which occur in both diseases, remains tobe defined. In 76 patients with Crohn's disease, 61patients with ulcerative colitis, 105 first-degreerelatives of patients with Crohn's disease, 101first-degree relatives of patients with ulcerativecolitis, and 40 healthy unrelated controls antinuclearautoantibodies were detected by indirect immunofluorescence.Existence of autoantibodies was correlated with clinicalfeatures. Eighteen percent of patients with Crohn'sdisease (14/76), 43% of patients with ulcerative colitis (26/61), 13% of relatives of patientswith Crohn's disease (14/105), 24% of relatives ofulcerative colitis patients (24/101), and 2% of thehealthy controls (1/40) were positive for antinuclear autoantibodies. The difference between controlsand patients and the first-degree relatives of patientswith ulcerative colitis, respectively, was statisticallysignificant (P ≤ 0.0144). In ulcerative colitis, the existence of antinuclear autoantibodies wasnegatively correlated with immunosuppressive therapy orextraintestinal manifestations (P = 0.0004 and 0.0273,respectively). Antinuclear autoantibodies may represent a factor disposing to the developmentof ulcerative colitis.