title: Usefulness of C-reactive protein as a disease activity marker in Crohn's disease according to the location of disease.
abstract: OBJECTIVE
  C-reactive protein (CRP) is a serologic activity marker in Crohn's disease (CD), but it may be less useful in evaluating CD activity in ileal CD patients. We aimed to investigate the usefulness of CRP as a disease activity marker in CD according to disease location.
  
  
  METHODS
  Korean CD patients in a single hospital were evaluated. Factors associated with elevated CRP concentration at the time of diagnosis of CD and the association between the physician's prediction regarding upcoming surgery and the sites of the lesions directly related to surgery were analyzed.
  
  
  RESULTS
  Of 435 CD patients, 25.7%, 6.9%, and 67.4% had ileal, colonic, and ileocolonic CD, respectively. Multivariate analysis revealed that an elevated erythrocyte sedimentation rate, reduced serum albumin, CD activity index (CDAI) >220, and ileocolonic/colonic location were associated with an elevated CRP level and that the CRP level was significantly correlated with the CDAI in all CD patients (γ=0.466, p<0.01). However, the correlation coefficient was dependent on the location, with values of 0.395, 0.456, and 0.527 in patients with an ileal, ileocolonic, and colonic disease location, respectively. Surgery for ileal lesions was less predictable than surgery for ileocolonic or colonic lesions during follow-up.
  
  
  CONCLUSIONS
  CRP is less useful as a disease activity marker in patients with ileal CD than those with ileocolonic or colonic CD.
authors.affiliation: Inflammatory Bowel Disease Center, Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Dong Hoon
authors.initials: DH
authors.lastname: Yang
authors.affiliation: Inflammatory Bowel Disease Center, Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Suk Kyun
authors.initials: SK
authors.lastname: Yang
authors.affiliation: Inflammatory Bowel Disease Center, Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Sang Hyoung
authors.initials: SH
authors.lastname: Park
authors.affiliation: Inflammatory Bowel Disease Center, Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Ho Su
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Inflammatory Bowel Disease Center, Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Sun Jin
authors.initials: SJ
authors.lastname: Boo
authors.affiliation: Inflammatory Bowel Disease Center, Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Jae Ho
authors.initials: JH
authors.lastname: Park
authors.affiliation: Inflammatory Bowel Disease Center, Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Soo Young
authors.initials: SY
authors.lastname: Na
authors.affiliation: Inflammatory Bowel Disease Center, Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Kee Wook
authors.initials: KW
authors.lastname: Jung
authors.affiliation: Inflammatory Bowel Disease Center, Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Kyung Jo
authors.initials: KJ
authors.lastname: Kim
authors.affiliation: Inflammatory Bowel Disease Center, Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Byong Duk
authors.initials: BD
authors.lastname: Ye
authors.affiliation: Inflammatory Bowel Disease Center, Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Jeong Sik
authors.initials: JS
authors.lastname: Byeon
authors.affiliation: Inflammatory Bowel Disease Center, Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Seung Jae
authors.initials: SJ
authors.lastname: Myung
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001799:Blood Sedimentation; D002097:C-Reactive Protein / Q000032:analysis*; D002648:Child; D003106:Colon / Q000473:pathology; D003424:Crohn Disease / Q000097:blood / Q000175:diagnosis* / Q000473:pathology; D005260:Female; D006801:Humans; D007082:Ileum / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012709:Serum Albumin / Q000032:analysis; D012720:Severity of Illness Index; D055815:Young Adult
chemical_list: D015415:Biomarkers; D012709:Serum Albumin; D002097:C-Reactive Protein
keywords: C-reactive protein; Crohn disease; Inflammation