No conclusive evidence of an epidemiological relation between Klebsiella and ankylosing spondylitis.

Fifty-six patients with ankylosing spondylitis and 87 healthy controls were screened for Klebsiella strains in their stools using a new highly sensitive culture medium. The presence of Klebsiella strains in the patient group was compared with activity of the disease. In a dynamic study changes in Klebsiella quantity over a period of 3 months were compared with changes in disease activity over the same period. The patient and control group showed similar percentages of Klebsiella carriage. In the patient group no temporal relation could be found between activity of the disease and the presence of Klebsiella in the intestinal tract.