The intra-individual variability of faecal calprotectin: A prospective study in patients with active ulcerative colitis

作者：Anders Lasson, Per‐Ove Stotzer, Lena Öhman, Stefan Isaksson, Maria Sapnara, Hans Strid · 发表于：Journal of Crohn s and Colitis · 年份：2014 · DOI：10.1016/j.crohns.2014.06.002 · 被引用次数：217 · 研究领域：Inflammatory Bowel Disease、S100 Proteins and Annexins、Infant Nutrition and Health

BACKGROUND AND AIMS: Leukocyte-derived proteins in faeces, especially calprotectin, are increasingly used to assess disease activity in ulcerative colitis. The objectives of the present study were to assess the importance of factors related to the stool sampling procedure. METHODS: For 2 days, patients with active ulcerative colitis collected two stool samples at each bowel movement. The time of defecation, consistency and presence of blood were self-recorded in a diary. The variability in the concentrations of calprotectin during the day and between two consecutive days was assessed, as was the stability of calprotectin concentrations in samples stored at room temperature. RESULTS: Altogether, 18 patients collected 287 stool samples. The intraclass correlation coefficient in pairs of samples from 132 bowel movements was 0.79 (95% CI 0.48-0.90). The median individual coefficient of variation in samples collected during the same day was 52% (4-178). There was a correlation between the level of calprotectin and the time between bowel movements (r = 0.5; p = 0.013). After 3 days at room temperature the calprotectin concentrations in stool samples were unchanged, but after 7 days a significant (p < 0.01) decrease was found (mean 28%; 95% CI 0.10-0.47). CONCLUSION: The present data reveal a great variability in the concentrations of calprotectin in stool samples collected during a single day. Since the levels of calprotectin increased with longer time between the bowel movements, ...