Histopathological evaluation and risk factors related to the development of pouchitis in patients with ileal pouches for ulcerative colitis

Abstract

OBJECTIVE:Many changes in mucosal morphology are observed following ileal pouch construction, including colonic metaplasia and dysplasia. Additionally, one rare but potential complication is the development of adenocarcinoma of the reservoir. The aim of this study was to evaluate the most frequently observed histopathological changes in ileal pouches and to correlate these changes with potential risk factors for complications.METHODS:A total of 41 patients were enrolled in the study and divided into the following three groups: a non-pouchitis group (group 1) (n = 20; 8 males; mean age: 47.5 years) demonstrating optimal outcome; a pouchitis without antibiotics group (group 2) (n = 14; 4 males; mean age: 47 years), containing individuals with pouchitis who did not receive treatment with antibiotics; and a pouchitis plus antibiotics group (group 3) (n = 7; 3 males; mean age: 41 years), containing those patients with pouchitis who were administered antibiotics. Ileal pouch endoscopy was performed, and tissue biopsy samples were collected for histopathological analysis.RESULTS:Colonic metaplasia was found in 15 (36.6%) of the 41 patients evaluated; of these, five (25%) were from group 1, eight (57.1%) were from group 2, and two (28.6%) were from group 3. However, no correlation was established between the presence of metaplasia and pouchitis (p = 0.17). and no differences in mucosal atrophy or the degree of chronic or acute inflammation were observed between groups 1, 2, and 3 (p>0.45). Moreover, no dysplasia or neoplastic changes were detected. However, the degree of mucosal atrophy correlated well with the time of postoperative follow-up (p = 0.05).CONCLUSIONS:The degree of mucosal atrophy, the presence of colonic metaplasia, and the degree of acute or chronic inflammation do not appear to constitute risk factors for the development of pouchitis. Moreover, we observed that longer postoperative follow-up times were associated with greater degrees of mucosal atrophy.

Development of a total colectomy and ileorectal anastomosis rat model to evaluate colonic metaplasia

“…5, 27 Similar to other studies, 18, 19 some villous blunting was seen in areas near the anastomosis at the study endpoint. Contrary to a previous report, 17 we identified colonic metaplasia (both villous blunting and presence of sulfomucin) in 70% of rats at the study endpoint.…”

Review article: the pathogenesis of pouchitis

“…Villus atrophy and crypt hyperplasia (termed 'colonic metaplasia') are two of the most common histological changes that occur in most, if not all, ileal pouches. [7][8][9][10][11][12][13][14][15][16] In fact, some studies have shown that the degree of colonic metaplasia correlates with pouchitis. [17][18][19] Pouchitis is the most common complication of IPAA, but its pathogenesis is still largely unknown.…”