Original ArticleAge-dependent variation of fecal calprotectin in cystic fibrosis and healthy children

BackgroundFecal calprotectin may be used as a non-invasive method to assess the effect of novel therapies on the gut in cystic fibrosis (CF).MethodStools from CF patients and healthy controls (HC) (0-10 years old) were prospectively collected for evaluation of temporal trends.Results130 CF samples (64 subjects) and 114 HC samples (101 subjects) were collected. Overall, fecal calprotectin levels were different in CF patients and HC from 0 to 10 years (P = 0.0002). Fecal calprotectin in CF was significantly lower than HC from 0 to 1 years (P = 0.03) and demonstrated an upward trajectory until 4 years. From > 4 to 10 years calprotectin was consistently higher in CF patients compared with HC (P = 0.007).ConclusionsFecal calprotectin levels in children with CF and HC were age-dependent and had distinct trajectories. Careful interpretation of calprotectin is required if used in drug trials for CF, particularly in children less than 4 years old.