Isolation of Chlamydia trachomatis from the lower digestive tract.

Chlamydia trachomatis was isolated from ten of 188 biopsies (5.3%) obtained from different parts of the lower digestive tract. Patients (mean age 37.0 years) presented with ulcerative proctitis, Crohn's disease, mild colitis or ulcerative colitis. Seven rectal biopsies, two biopsies from the sigmoid flexure and one caecal biopsy were positive for chlamydial isolation whereas all biopsies taken from the colon ascendens, transversum or descendens and from the terminal ileum were negative. We conclude that isolation of C. trachomatis is most effective from rectal and sigmoidal biopsies and is a rare event from other sites of the lower digestive tract.