Association between disease duration and usefulness of fecal calprotectin measurement in patients with Crohn's disease

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. The aim of the study was to assess whether disease duration affects the diagnostic utility of fecal calprotectin measurement in patients with CD. 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. 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