Fecal calprotectin as a marker of the severity of mucosal inflammation in children with inflammatory bowel disease.

Objectives: Inflammatory bowel disease (IBD) in children has a remitting and relapsing course. The aim of our study was to evaluate the value of fecal calprotectin (FC), C-reactive protein (CRP), and clinical scores in predicting endoscopic and histological lesions in children with IBD.

Methods: A total of 68 children with IBD (29 with ulcerative colitis (UC), 39 with Crohn's disease (CD), mean age 14.2 years) were included in the study. We retrospectively reviewed clinical scores (PUCAI, PCDAI), CRP values, endoscopic, and histological data as well as FC values in all included children.

Results: In children with UC, the correlation between the histological lesions and FC (r = 0.609, p < 0.01), CRP (r = 0.390, n.s.), or PUCAI (r = 0.535, p < 0.05) was higher than for children with CD (FC r =  0.490, n.s.; CRP r =  0.269, n.s.; PCDAI r = 0.257, n.s.). The correlation between endoscopy scores and the same parameters yielded similar findings (UC: FC r = 0.628, p < 0.01; CRP r = 0.387, n.s.; PUCAI r = 0.256, n.s.; CD: FC r = 0.516, p < 0.05; CRP r = 0.238, n.s.; PCDAI r = 0.267, n.s.). The correlation between FC and PUCAI (r = 0.532, p < 0.01) was higher than that between CRP and PUCAI (r = 0.424, p < 0.01). However, the correlation between FC and PCDAI (0.384, p < 0.01) is lower than that between CRP and PCDAI (r = 0.447, p < 0.01).

Conclusion: FC is a better predictor of the severity of endoscopic and histological lesions than CRP or disease activity scores, especially for UC. FC, as a noninvasive marker, could possibly be used to reduce the number of endoscopic procedures in children with a confirmed diagnosis of IBD.