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P167 Changes of diagnosis after colectomy: a single-center experience


 
 
 Total proctocolectomy (TPC) is relatively common in inflammatory bowel diseases (IBD), occurring more in ulcerative colitis (UC) as compared with Crohn’s disease (CD) (20.3% vs. 10.5% of patients). Among IBD patients undergoing colectomy, a major complication affecting the clinical outcome is the change of diagnosis. In clinical practice, approximately 5% to 20.9% of UC patients develop CD of the pouch or of the neo-small intestine. The incidence of UC diagnosis after colectomy for complicated colonic CD is less clear. Drugs and progression of the disease can dramatically change the histological findings in this patients; endoscopy after baseline can be atypical and doesn’t provide cross-sectional informations about bowel wall. Aim of the study is to assess the rate of diagnosis change after colectomy in our center.
 
 
 
 All the IBD patients who consecutively underwent TPC with ileal pouch–anal anastomosis (IPAA) or permanent ileostomy from January 2015 to December 2018 in our IBD Unit were included in this observational, retrospective study.
 
 
 
 Thirty-one patients (22 UC; 22 Males) were included in the study. Among UC patients 14 had pancolitis and 8 a left-sided colitis. Seven were steroid-resistant, 8 were steroid-dependant, 14 experienced failure to medical treatment (one or more biologics) and 8 patients had dysplasia. Mayo endoscopic score was 3 in all patients, but 3. In 5 out of 22 UC patients (22%), diagnosis changed in colonic CD after evaluation of the surgical specime by the pathologist. Four of these patients were referred to our institution by peripheral hospitals with a severe disease, requiring urgent/emergent colectomy and was therefore performed only a proctosigmoidoscopy. Permanent ileostomy was performed in all 5 patients. Among the 8 colonic CD patients 2 were steroid-resistant, 2 were steroid-dependant, 7 failed to one or more biologics, 1 showed mucosal dysplasia and two had bowel stenosis. Two patients (20%) were diagnosed as UC after TPC and IPAA could therefore be performed.
 
 
 
 The change of diagnosis leads to a different surgical outcome, resulting in a worsening in former UC patients and in an improvement in former CD patients. An accurate clinical, endoscopic and histological re-evaluation of the patients is therefore mandatory before TPC. Providing an elevated number of specimens to dedicated pathologists is advisable to avoid potential complications especially in UC patients.
