title: Identification of pathologic features associated with "ulcerative colitis-like" Crohn's disease.
abstract: OBJECTIVE
  To identify pathologic features associated with this "ulcerative colitis (UC)-like" subgroup of Crohn's disease (CD).
  
  
  METHODS
  Seventeen subjects diagnosed as having UC who underwent proctocolectomy (RPC) from 2003-2007 and subsequently developed CD of the ileal pouch were identified. UC was diagnosed based on pre-operative clinical, endoscopic, and pathologic studies. Eighteen patients who underwent RPC for UC within the same time period without subsequently developing CD were randomly selected and used as controls. Pathology reports and histological slides were reviewed for a wide range of gross and microscopic pathological features, as well as extent of disease. The demographics, gross description and histopathology of the resection specimens were reviewed and compared between the two groups.
  
  
  RESULTS
  Patients with "UC-like" CD were on average 13 years younger than those with "true" UC (P < 0.01). More severe disease in the proximal involved region and active ileitis with/without architectural distortion were observed in 6 of 17 (35%) and 7 of 17 (41%) "UC-like" CD cases, respectively, but in none of the "true" UC cases (P < 0.05). Active appendicitis occurred in 8 of 16 (50%) "UC-like" CD cases but in only two (11%) "true" UC cases (P < 0.05). Conspicuous lamina propria neutrophils were more specific for "UC-like" CD (76% vs 22%, P < 0.05). In addition, prominent lymphoid aggregates tended to be more common in "UC-like" CD (P = 0.07). The "true" UC group contained a greater number of cases with severe activity (78% vs 47%). Therefore, the features more commonly seen in "UC-like" CD were not due to a more severe disease process. Crohn's granulomas and transmural inflammation in non-ulcerated areas were absent in both groups.
  
  
  CONCLUSIONS
  More severe disease in the proximal involved region, terminal ileum involvement, active appendicitis, and prominent lamina propria neutrophils may be morphological factors associated with "UC-like" CD.
authors.affiliation: Samuel D James, M Kay Washington, Chanjuan Shi, Departments of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, United States.
authors.forename: Samuel D
authors.initials: SD
authors.lastname: James
authors.affiliation: Samuel D James, M Kay Washington, Chanjuan Shi, Departments of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, United States.
authors.forename: Paul E
authors.initials: PE
authors.lastname: Wise
authors.affiliation: Samuel D James, M Kay Washington, Chanjuan Shi, Departments of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, United States.
authors.forename: Tania
authors.initials: T
authors.lastname: Zuluaga-Toro
authors.affiliation: Samuel D James, M Kay Washington, Chanjuan Shi, Departments of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, United States.
authors.forename: David A
authors.initials: DA
authors.lastname: Schwartz
authors.affiliation: Samuel D James, M Kay Washington, Chanjuan Shi, Departments of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, United States.
authors.forename: M Kay
authors.initials: MK
authors.lastname: Washington
authors.affiliation: Samuel D James, M Kay Washington, Chanjuan Shi, Departments of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, United States.
authors.forename: Chanjuan
authors.initials: C
authors.lastname: Shi
mesh_terms: D000328:Adult; D003093:Colitis, Ulcerative / Q000145:classification / Q000473:pathology* / Q000601:surgery; D003106:Colon / Q000473:pathology* / Q000601:surgery; D039021:Colonic Pouches / Q000473:pathology*; D003424:Crohn Disease / Q000145:classification / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D007082:Ileum / Q000473:pathology* / Q000601:surgery; D007413:Intestinal Mucosa / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000473:pathology; D011237:Predictive Value of Tests; D016737:Proctocolectomy, Restorative; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D016896:Treatment Outcome; D055815:Young Adult
keywords: Crohn’s colitis; Inflammatory bowel disease; Ulcerative colitis; Ulcerative colitis-like Crohn’s disease