Long-term follow-up after ileoanal pouch procedure: algorithm for diagnosis, classification, and management of pouchitis.

PURPOSE: Inflammation of the ileoanal pouch (pouchitis) is one of the main complications after restorative proctocolectomy, yet its cause remains poorly understood. A standardized definition and diagnostic procedures in pouchitis are lacking.

METHOD: We analyzed all cases of pouchitis occurring in a group of 308 patients (210 with ulcerative colitis, 98 with familial adenomatous polyposis) who took part in a prospective long-term follow-up program. The severity of pouchitis was measured using a pouchitis activity score (Heidelberg Pouchitis Activity Score). An algorithm for the classification and management of pouchitis was established which enables the clinician: 1) to determine the severity of pouchitis, 2) to differentiate between primary pouchitis and pouchitis caused by surgical complications (secondary pouchitis), and 3) to evaluate the course (acute vs. chronic (> 3 months)).

RESULTS: The median duration of follow-up was 48 (range, 13-119) months. At least one episode of pouchitis was diagnosed in 29 percent of patients with ulcerative colitis and in 2 percent of familial adenomatous polyposis patients. Secondary pouchitis occurred in 6 percent of ulcerative colitis patients and was cured by surgical treatment in 13 (87 percent) of 15 cases. Primary pouchitis was diagnosed in 23 percent of ulcerative colitis patients, including 6 percent of all ulcerative colitis patients with chronic primary pouchitis. The latter showed poor response to medical treatment. In one case multifocal high-grade dysplasia occurred. Histologic examination of the excised pouch identified a carcinoma originating from the ileal mucosa.

CONCLUSIONS: Ulcerative colitis patients after restorative proctocolectomy face a high risk of developing pouchitis. The algorithm used in this study was highly efficient in identifying patients with a secondary pouchitis who require surgical treatment and patients with chronic primary pouchitis. For the latter, long-term surveillance seems mandatory because of the risk of malignant transformation of the pouch mucosa.