title: Association between disease duration and usefulness of fecal calprotectin measurement in patients with Crohn's disease.
abstract: BACKGROUND
  Fecal calprotectin is a useful diagnostic marker in the assessment of Crohn's disease (CD) activity. However, the clinical picture of CD is diverse and its phenotypes change with disease duration: in the early phase, an inflammatory activity dominates and, with time, an increasing percentage of patients develop strictures and fistulas.
  
  
  OBJECTIVE
  The aim of the study was to assess whether disease duration affects the diagnostic utility of fecal calprotectin measurement in patients with CD.
  
  
  METHODS
  A total of 150 patients with CD were prospectively enrolled into the study. CD activity was assessed by magnetic resonance enterography by calculating the Simple Enterographic Activity Score for Crohn's Disease. Endoscopic activity was assessed using the Simple Endoscopic Score for Crohn's Disease (SES‑CD). The blood levels of inflammatory markers and the fecal calprotectin concentration were assessed using an enzyme‑linked immunosorbent assay. Patients were divided into 2 subgroups depending on CD duration: less than 10 years and 10 years or longer from the diagnosis.
  
  
  RESULTS
  Patients with longer disease duration had lower inflammatory CD activity assessed by biochemical, endoscopic, and radiographic tests. Fecal calprotectin showed a tendency for lower concentrations in this subgroup (106.5 ±93.2 mg/l vs. 135.7 ±128.8 mg/l; P >0.05). A stricturing or penetrating CD phenotype was observed significantly more often in patients with long‑lasting CD (P <0.04). Nevertheless, in both study subgroups, fecal calprotectin was significantly correlated with SES‑CD, C‑reactive protein levels, and platelet count.
  
  
  CONCLUSIONS
  Disease duration and time‑dependent changes of the CD phenotype do not affect the diagnostic utility of the fecal calprotectin measurement. Reliability of this noninvasive biochemical method in the assessment of disease activity is similar in all patients with CD; therefore, it may be used independently of the time from diagnosis.
authors.forename: Piotr
authors.initials: P
authors.lastname: Eder
authors.forename: Kamila
authors.initials: K
authors.lastname: Stawczyk-Eder
authors.forename: Liliana
authors.initials: L
authors.lastname: Łykowska-Szuber
authors.forename: Iwona
authors.initials: I
authors.lastname: Krela-Kaźmierczak
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Klimczak
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Szymczak
authors.forename: Patrycja
authors.initials: P
authors.lastname: Szachta
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Linke
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000032:analysis; D002097:C-Reactive Protein / Q000032:analysis*; D003424:Crohn Disease / Q000175:diagnosis*; D005243:Feces / Q000737:chemistry*; D005260:Female; D006801:Humans; D039841:Leukocyte L1 Antigen Complex / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D015203:Reproducibility of Results; D013997:Time Factors
chemical_list: D015415:Biomarkers; D039841:Leukocyte L1 Antigen Complex; D002097:C-Reactive Protein