Consecutive fecal calprotectin measurements for predicting relapse in pediatric Crohn's disease patients

BACKGROUND Asymptomatic children with Crohn's disease (CD) require ongoing monitoring to ensure early recognition of a disease exacerbation. AIM In a cohort of pediatric CD patients, we aimed to assess the utility of serial fecal calprotectin measurements to detect intestinal inflammatory activity and predict disease relapse. METHODS In this prospective longitudinal cohort study, children with CD on infliximab therapy in clinical remission were included. Fecal calprotectin levels were assessed at baseline and at subsequent 2-5 visits. Clinical and biochemical disease activity were assessed using the Pediatric Crohn's Disease Activity Index, Creactive protein and erythrocyte sedimentation rate at baseline and at visits over the following 18 mo. RESULTS 53 children were included and eighteen patients (34%) had a clinical disease relapse during the study. Baseline fecal calprotectin levels were higher in patients that developed symptomatic relapse [median (interquartile range), relapse 723 mu g/g (283-1758) vs 244 mu g/g (61-627), P = 0.02]. Fecal calprotectin levels > 250 mu g/g demonstrated good predictive accuracy of a clinical flare within 3 mo (area under the receiver operator curve was 0.86, 95% confidence limits 0.781 to 0.937). CONCLUSION Routine fecal calprotectin testing in children with CD in clinical remission is useful to predict relapse. Levels > 250 mu g/g are a good predictor of relapse in the following 3 mo. This information is important to guide monitoring standards used in this population.