title: Is faecal calprotectin equally useful in all Crohn's disease locations? A prospective, comparative study.
abstract: BACKGROUND
  There are data suggesting that the diagnostic usefulness of faecal calprotectin (FC) may vary depending on the Crohn's disease (CD) location. The aim of the study was to compare the diagnostic usefulness of FC in CD patients with different disease locations.
  
  
  METHODS
  We prospectively enrolled 120 CD patients in the study. Disease activity was assessed by using Crohn's Disease Activity Index (CDAI), biochemical markers, and endoscopic and radiographic methods. Faecal calprotectin concentration was assessed in single stool samples by using the ELISA method.
  
  
  RESULTS
  Among all patients, 54 (45%) had ileocolonic CD location, 44 (36.5%) had isolated small bowel location, and 22 (18.5%) had colonic CD location. FC correlated significantly with C-reactive protein concentration and endoscopic and radiographic activity among patients with isolated small bowel CD (p = 0.03, r = 0.32; p < 0.0001, r = 0.78; p = 0.03, r = 0.35; respectively) and with C-reactive protein and endoscopic activity in isolated colonic CD (p = 0.0009, r = 0.7; p = 0.0002, r = 0.78; respectively). CDAI and inflammatory biochemical markers did not correlate with endoscopic and radiographic assessment in small bowel CD. In patients with ileocolonic CD, FC correlated significantly with endoscopy (p = 0.006, r = 0.5), radiographic assessment (p = 0.04, r = 0.3), CDAI (p = 0.0006, r = 0.5) and the majority of biochemical markers.
  
  
  CONCLUSIONS
  Faecal calprotectin is a useful diagnostic marker in all CD patients. Although its usefulness in small bowel CD seems to be the lowest, it should be utilized particularly in this disease location because of the lack of other reliable, non-invasive diagnostic methods.
authors.affiliation: Department of Gastroenterology, Human Nutrition and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Kamila
authors.initials: K
authors.lastname: Stawczyk-Eder
authors.affiliation: Department of Gastroenterology, Human Nutrition and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Eder
authors.affiliation: Department of Gastroenterology, Human Nutrition and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Liliana
authors.initials: L
authors.lastname: Lykowska-Szuber
authors.affiliation: Department of Gastroenterology, Human Nutrition and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Krela-Kazmierczak
authors.affiliation: Department of Gastroenterology, Human Nutrition and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Klimczak
authors.affiliation: Department of Gastroenterology, Human Nutrition and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Szymczak
authors.affiliation: Institute of Microecology, Poznan, Poland.
authors.forename: Patrycja
authors.initials: P
authors.lastname: Szachta
authors.affiliation: Department of General Radiology, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Katulska
authors.affiliation: Department of Gastroenterology, Human Nutrition and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Linke
keywords: disease activity; endoscopy; inflammatory bowel diseases; magnetic resonance enterography