[Fecal calprotectin as a biomarker to distinguish between organic and functional gastrointestinal disease]. / Calprotectina fecal como marcador diferencial entre patología gastrointestinal orgánica y funcional.

INTRODUCTION: There is growing evidence showing the importance of the fecal calprotectin assay in differentiating organic from functional gastrointestinal disease. It is a simple, non-invasive biomarker that is especially useful in children, who may require general anesthesia for colonoscopy. The aim of this study was to assess the use and sensitivity of fecal calprotectin (FCP) in pediatric patients with signs and symptoms of IBD to avoid unnecessary invasive techniques and to distinguish between organic and functional gastrointestinal pathology. MATERIAL AND METHODS: A single stool sample was collected from 47 children (mean age: 10.1 years) referred for non-specific gastrointestinal symptoms suggestive of organicity. On the basis of clinical criteria 13 children had functional bowel disorders and 34 had organic gastrointestinal disease, 15 with IBD and 19 with other organic (non-IBD) gastrointestinal conditions. Thirty healthy children were included as controls. Calprotectin concentrations were measured by enzyme immunoassay. RESULTS: Children with IBD had FCP levels [median (interquartile range); 1,219 microg/g (322-2,967 microg/g)] higher than children with functional gastrointestinal disease [20 microg/g (16-25 microg/g); p < 0.0001], those with organic non-IBD disease [113 microg/g (36-193 microg/g); p = 0.002], and healthy children [25 microg/g (19.2-32.5 microg/g); p < 0.0001]. Fecal calprotectin concentration also was significantly higher in children with organic (non-IBD) disease as compared to controls (p = 0.004) and children with functional pathology (p = 0.002). FCP levels were similar in controls and children with functional gastrointestinal disease (p = 0.264). DISCUSSION: CPF is a sensitive, but not disease-specific, marker to identify patients with IBD who should undergo diagnostic colonoscopy, and to avoid unnecessary invasive procedures in patients with functional gastrointestinal disorders.