title: Nonbloody Diarrhea but Not Significant Weight Loss at Diagnosis Is Associated with the Development of Denovo Crohn's Disease After Ileal Pouch-anal Anastomosis for Ulcerative Colitis.
abstract: BACKGROUND
  Denovo Crohn's disease (CD) develops in 5% to 10% of patients after ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC) leading to increased morbidity and rates of pouch failure. Initial nonbloody diarrhea and weight loss at diagnosis are independent risk factors for a change in diagnosis from UC to CD in nonsurgical patients. We investigated whether these features were risk factors for denovo CD in a longitudinal cohort of patients with UC undergoing IPAA.
  
  
  METHODS
  Prospective profiles of patients with UC undergoing IPAA followed over a 22-year period by 1 surgeon were analyzed. Denovo CD was diagnosed when mucosal inflammation (5 or more ulcers) involved the small bowel mucosa proximal to the ileal pouch any time after surgery and/or when a pouch fistula or other perianal complication developed more than 3 months after ileostomy closure. Patients with inflammatory bowel disease unclassified, acute pouchitis, chronic pouchitis, and those lost to follow-up were excluded from analysis. Cox regression analysis was performed for statistical significance.
  
  
  RESULTS
  Of the 199 study patients included in the analysis, denovo CD developed in 42 patients (21%). Patients who developed denovo CD had an increased incidence of nonbloody diarrhea (n = 12; 29%) compared with patients who had no evidence of pouch inflammation (n = 25; 16%) (P = 0.03). In contrast, the incidence of weight loss was not significantly increased in patients with denovo CD (n = 7; 17%) compared with patients who never had pouch inflammation (n = 16; 10%) (P = 0.12).
  
  
  CONCLUSIONS
  Initial nonbloody diarrhea is associated with denovo CD after IPAA. This association warrants close consideration before surgery.
authors.affiliation: *Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California; †Division of Gastroenterology, Inflammatory Bowel Disease Center, Cedars-Sinai Medical Center, Los Angeles, California; ‡Department of Pediatrics, Inflammatory Bowel Disease Center, Cedars-Sinai Medical Center, Los Angeles, California; and §Division of Colon and Rectal Surgery, Inflammatory Bowel Disease Center, Cedars-Sinai Medical Center, Los Angeles, California.
authors.forename: Shahzad
authors.initials: S
authors.lastname: Ahmed
authors.forename: Gil
authors.initials: G
authors.lastname: Melmed
authors.forename: Dermot
authors.initials: D
authors.lastname: McGovern
authors.forename: Lori A
authors.initials: LA
authors.lastname: Robbins
authors.forename: David
authors.initials: D
authors.lastname: Shih
authors.forename: Eric
authors.initials: E
authors.lastname: Vasiliauskas
authors.forename: Namita
authors.initials: N
authors.lastname: Singh
authors.forename: Shervin
authors.initials: S
authors.lastname: Rabidzadeh
authors.forename: Andrew
authors.initials: A
authors.lastname: Ippoliti
authors.forename: Stephan
authors.initials: S
authors.lastname: Targan
authors.forename: Phillip
authors.initials: P
authors.lastname: Fleshner
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001003:Anal Canal / Q000601:surgery*; D000714:Anastomosis, Surgical / Q000009:adverse effects*; D002140:California / Q000453:epidemiology; D002648:Child; D003093:Colitis, Ulcerative / Q000601:surgery*; D039021:Colonic Pouches / Q000009:adverse effects*; D003424:Crohn Disease / Q000175:diagnosis / Q000209:etiology*; D003967:Diarrhea / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D015431:Weight Loss; D055815:Young Adult