Background: Large bowel localization of Crohn's disease occurs in more than 60% of all patients. In approximately 50% of those patients small bowel localization coexists, while in the other half, colon is the only localization. Rectum is involved in about 40% of patients. At least 30% of patients with colonic Crohn' disease will require surgery during their lifetime. For patients with extensive colonic disease the first-choice surgical therapy consist in rectum sparing colectomy and ileorectal anastomosis.
In this study we evaluated the long-term outcome of patients with ileo-rectal anastomosis relatively to the disease localization prior to surgery.
Methods: We retrospectively went through clinical records of patients followed at our referral IBD center who underwent colectomy and ileo-rectal anastomosis for Crohn's colitis to evaluate if there were differences in relapse rate among patients with or without involvement of ileum and/or rectum.
Results: Between 1996 and 2016 86 patients underwent colectomy and ileo-rectal anastomosis for Crohn's colitis. We excluded from the study patients with perianal active disease, patients with subsequent diagnosis of ulcerative colitis and patients with less than five years follow-up.
Fifteen patients had no ileum or rectum involvement prior to surgery (group A); 19 had colon and rectum involvement (group B), 23 had colon and ileum involvement, but no rectal localization (group C); and 8 patients had both localization in ileum and rectum, as well as of the colon (group D). No one patient with ileum and rectum sparing colitis (group A) had disease relapse. 15 out 19 patients (79%) of group B had disease relapse after a median time of 2.1 years (0.5–7), mostly in the rectum (73%). 91% (21/23) of patients in group C experienced disease relapse (47% ileum, 19% rectum, 9% both sides) after an average of 3.2 years (0.5–9). 7 out of 8 patients of group D had a disease relapse (42% ileum, 42% rectum, 14% both) after a median time of 2.2 years (0.5–5). For groups B and C at least two thirds of patients required immunosuppressive therapy (thiopurines or anti-TNFα) to treat disease relapse, while in group D every patient with disease relapse needed anti-TNFα therapy. 3 patients of Group B (15%) and 2 patients of group D (25%) underwent permanent ileostomy.
Conclusions: Our data show that patients with Crohn's colitis with rectum and ileum sparing who underwent colectomy with ileo-rectal anastomosis may represent a subgroup of patients in which Crohn's disease can be cured by surgery. Obviously this preliminary data should be confirmed by further studies.