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, C-reactive 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 μg/g (283-1758) 244 μg/g (61-627), = 0.02]. Fecal calprotectin levels > 250 μg/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 μg/g are a good predictor of relapse in the following 3 mo. This information is important to guide monitoring standards used in this population.