Abstract
A study of 59 patients with definite ankylosing spondylitis and 41 comparable hospital outpatients with fractures has been undertaken to determine if the presence of faecal Klebsiella aerogenes is related to clinical activity of the spinal disease and its extraspinal features. The frequencies of fecal K. aerogenes were similar in both patients and controls and were not significantly related to spinal disease activity. Careful inquiry about antibiotic treatment, dietary habits, and hospitalisation did not significantly influence the results. A significant association was found between the presence of faecal K. aerogenes and both acute non-granulomatous anterior uveitis (P less than 0.01) and peripheral synovitis in HLA B27 positive patients (P less than 0.05). These results suggest that K. aerogenes may have an aetiological role in the development of non-granulomatous anterior uveitis and peripheral arthritis in patients with ankylosing spondylitis but do not lend support to this organism having such a role in the spinal disease itself.