The combination of fecal calprotectin with ESR, CRP and albumin discriminates more accurately children with Crohn's disease.

Purpose: Increased fecal calprotectin is a sensitive marker of various types of intestinal inflammation. We investigated correlations between high fecal calprotectin concentration and serum inflammatory markers in children with different intestinal diseases with diarrhea with/without blood and/or abdominal pain, to test whether the combination of these markers can differentiate potential patients with inflammatory bowel disease.

Materials/methods: The study included 128 children with high fecal calprotectin concentration (>150ug/g) and symptoms suggesting bowel disorders, hospitalized in the years 2013- 2015. Twenty-six (20%) patients were diagnosed with Crohn's disease, 55 (43%) with ulcerative colitis, 32 (25%) with intestinal infection and 15 (12%) with food protein induced proctocolitis.

Results: Significantly increased inflammatory markers were detected in children with inflammatory bowel disease, with a correlation between calprotectin and erythrocyte sedimentation rate - ESR (R = 0.53), mean corpuscular volume - MCV (R=-0.64), red blood cell distribution width (R = 0.56), albumin (R = -0.52), hemoglobin (R = -0.53) only in Crohn's disease patients. To discriminate Crohn's disease patients from patients with intestinal infection and patients with food protein induced proctocolitis, AUC analysis was performed. It revealed that considering ESR, CRP and albumin as additional markers to fecal calprotectin significantly improved diagnostic performance (AUC 0.917, p = 0.038).

Conclusions: In children with abdominal pain and/or diarrhea, increased ESR, CRP and decreased albumin combined with a high fecal calprotectin level yields additional diagnostic value in screening potential patients with Crohn's disease. As far as differentiation of ulcerative colitis is concerned, low additional diagnostic value was found when high fecal calprotectin was combined with albumin.