Incidence and Severity of Prepouch Ileitis: A Distinct Disease Entity or a Manifestation of Refractory Pouchitis?

Restorative proctocolectomy with ileal pouch-anal anastomosis is the operation of choice for patients with treatment-refractory ulcerative colitis. However, after this intervention, up to 50% of patients develop pouchitis. Moreover, a subgroup will also develop inflammation in the afferent ileum proximal to the pouch, a condition named prepouch ileitis (PI).

Data on 546 patients who underwent ileal pouch-anal anastomosis for ulcerative colitis were retrospectively collected from 3 tertiary inflammatory bowel disease referral centers in the Netherlands, Belgium, and England. PI was considered present if there was endoscopic and histological inflammation in the afferent limb proximal to the pouch. Crohn's disease was excluded by reviewing the histology of colectomy resection specimens.

PI was present in 33/546 (6%) patients and all of these had concurrent pouchitis. One hundred forty-four (26%) patients had pouchitis without PI and 369 (68%) patients did not have inflammatory pouch disease. Of the 33 patients with PI, 6 (18%) received no specific treatment, 9 (27%) responded to antibiotics, and 18 (54%) required escalation in therapy to steroids/immunomodulators or anti-tumor necrosis factor agents. Potent immunosuppressive treatment was required more frequently in patients with PI than those with pouchitis alone.

PI is less common and more treatment refractory than pouchitis alone. Once PI is diagnosed, clinicians should be aware that response to antibiotic therapy is less likely than in pouchitis alone. Immunomodulatory therapy and escalation to anti-tumor necrosis factor agents should be considered early in cases of nonresponse. The suggestion that PI represents misdiagnosed Crohn's disease could not be substantiated in our cohort.