Lack of evidence for an association between infection with Chlamydia trachomatis and Crohn's disease, as indicated by micro-immunofluorescence antibody tests.

A significant difference has recently been reported in the occurrence of serum antibodies to the lymphogranuloma venereum (LGV) immunotypes of Chlamydia trachomatis in patients with Crohn's disease and controls. In the present study, sera from 107 patients with Crohn's disease, 33 males and 74 females, were tested for antibodies to C. trachomatis by an indirect immunofluorescence test, using two pools of antigens. These pools contained antigens to immunotypes TRIC D-K and LGV 1-3, respectively. None of the patients had IgM antibodies to the organism. IgG antibodies occurred significantly more often in the female than in male patients. No correlation could be demonstrated between activity and duration of Crohn's disease and the results of the antibody tests. For comparison, the sera of 50 puerperal women were studied. No difference in the occurence of IgG antibodies was found between patients and controls, neither when using the two pools of antigen, thus indicating that the antibodies detected had probably been induced by TRIC rather than LGV organisms. To conclude, the study did not indicate an association between Crohn's disease and infection with C. trachomatis.