title: Change in the diagnosis of inflammatory bowel disease: a hospital-based cohort study from Korea.
abstract: OBJECTIVE
  Accurately diagnosing inflammatory bowel disease (IBD) remains a challenge, but is crucial for providing proper management for affected patients. The aim of the present study was to evaluate the frequency of change in diagnosis in Korean patients who were referred to our institution with a diagnosis of IBD.
  
  
  METHODS
  We enrolled 1,444 patients diagnosed with ulcerative colitis (UC) and 1,452 diagnosed with Crohn's disease (CD), who had been referred to the Asan Medical Center between January 2010 and December 2014. These patients were assessed and subsequently classified as having UC, CD, indeterminate colitis, possible IBD, or non-IBD.
  
  
  RESULTS
  During a median follow-up of 15.9 months, 400 of the 2,896 patients (13.8%) analyzed in this study experienced a change in diagnosis. A change in diagnosis from UC to CD, or vice-versa, was made in 24 of 1,444 patients (1.7%) and 23 of 1,452 patients (1.6%), respectively. A change to a non-IBD diagnosis was the most common modification; 7.5% (108 of 1444) and 12.7% (184 of 1452) of the patients with a referral diagnosis of UC and CD, respectively, were reclassified as having non-IBD. Among the 292 patients who were ultimately determined not to have IBD, 135 (55 UC and 80 CD cases) had received IBD-related medication.
  
  
  CONCLUSIONS
  There are diagnostic uncertainties and difficulties in relation to IBD. Therefore, precise assessment and systematic follow-up are essential in the management of this condition.
authors.affiliation: Health Screening and Promotion Center, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Ho-Su
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Health Screening and Promotion Center, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Jaewon
authors.initials: J
authors.lastname: Choe
authors.affiliation: Health Screening and Promotion Center, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Hyo Jeong
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Sung Wook
authors.initials: SW
authors.lastname: Hwang
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Sang Hyoung
authors.initials: SH
authors.lastname: Park
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Dong-Hoon
authors.initials: DH
authors.lastname: Yang
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Kyung-Jo
authors.initials: KJ
authors.lastname: Kim
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Byong Duk
authors.initials: BD
authors.lastname: Ye
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Jeong-Sik
authors.initials: JS
authors.lastname: Byeon
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Seung-Jae
authors.initials: SJ
authors.lastname: Myung
authors.affiliation: Department of Colon and Rectal Surgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Yong Sik
authors.initials: YS
authors.lastname: Yoon
authors.affiliation: Department of Colon and Rectal Surgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Chang Sik
authors.initials: CS
authors.lastname: Yu
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Jin-Ho
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Suk-Kyun
authors.initials: SK
authors.lastname: Yang
keywords: Crohn disease; Diagnosis; Inflammatory bowel diseases; Ulcerative colitis