Fecal Calprotectin and Lactoferrin as Noninvasive Markers of Pediatric Inflammatory Bowel Disease

OBJECTIVE: To evaluate whether fecal calprotectin (FC) and fecal lactoferrin (FL) can be used as noninvasive markers in children and young people (4-17 years) with active inflammatory bowel disease (IBD). PATIENTS AND METHODS: Stool samples were collected from 3 groups of children: those with active IBD, control individuals with other gastrointestinal (GI) diseases (GI control) and control individuals with no GI disease (non-GI control). The number of patients for the FC assay was as follows: IBD = 26, GI control = 30, non-GI control = 25. The number of patients for the FL assay was as follows: IBD = 24, GI control = 26, non-GI = 24. FC and FL were measured by use of enzyme-linked immunoassays. RESULTS: The median concentrations of FC and FL in isolation, and their interaction, were significantly higher in the IBD group than in the GI and non-GI control groups (P < 0.001). Although the area under the curve, sensitivity, and specificity for FC, FL, and FC x FL interaction were significantly better than chance, FL consistently had the lowest area under the curve, and FC x FL consistently had the highest area under the curve. CONCLUSIONS: FC and FL are both significantly elevated in children with IBD, and the interaction of these 2 biomarkers may produce a better initial diagnostic test compared with their use in isolation.