Factors associated with disease activity of pouchitis after surgery for ulcerative colitis

Pouchitis occurs in 20% to 59% of patients operated on for ulcerative colitis. Several risk factors have been identified for the development of pouchitis. This study was undertaken to assess the incidence of pouchitis at least 5 years after ileal pouch-anal anastomosis for ulcerative colitis, and to evaluate possible predictive factors for inflammation activity.

A total of 107 subjects were enrolled (54 M, 53 F, mean age 45 years, range 23-69) with a J-pouch created between 1985 and 1994. Preoperative medical history was determined, an endoscopy performed, and biopsies taken from the pouch and neoterminal ileum above the pouch. Sera from all patients were tested for perinuclear antineutrophil cytoplasmic antibodies (pANCAs).

After a mean 7.5-years' follow-up time, the cumulative incidence of pouchitis was 58%. Risk for development of active inflammation (PDAI > or = 7) was significantly higher in patients with preoperative extraintestinal manifestations (OR 2.7, 95% CI 1.1-6.4, P=0.03). Patients who had had ankylosing spondylitis (AS) (OR 11.7, P=0.006) or iritis (OR 9.8, P=0.013) were especially at risk. Positive titres of pANCAs were associated with inflammation in the neoterminal ileum; 80% of patients with high pANCA levels (>100) had pouchitis. Current smokers tended to have a more benign disease course.

A correlation existed between the prevalence and titre of pANCAs and extent and disease activity of pouchitis. Chronic pouchitis may continuously stimulate the immunological process, keeping pANCAs at detectable levels. A strong correlation between AS, iritis and pouchitis suggests a common link in their pathogenesis.