Background: Calprotectin is an abundant neutrophil protein, which is extremely stable in feces. This study aimed to validate fecal calprotectin as a marker of bowel inflammation against invasive measures in children with inflammatory bowel disease (IBD), including colitis and small bowel Crohn disease.
Methods: Fecal calprotectin was measured using a simple enzyme-linked immunosorbent assay in 36 spot stool samples from 22 children before colonoscopy and from 14 children before technetium-99 ( 99 Tc) scanning. Using standard scoring systems, the severity of inflammation was assessed macroscopically and histologically at six standard sites in those who underwent colonoscopy and also at six standard sites in those who underwent 99 Tc scanning. The subscores from each site were summated to give combined severity and extent scores for macroscopic and for histologic inflammation in the group undergoing colonoscopy and total inflammation in the group undergoing 99 Tc scanning.
Results: In the 22 children who underwent colonoscopy, median fecal calprotectin was 4.9 mg/L (0.1–272.5 mg/L) (range). Disease groups included six normal cases, nine ulcerative colitis cases, two isolated Crohn colitis cases, two indeterminate colitis cases, and three allergic colitis cases. Fecal calprotectin correlated closely with colonic macroscopic inflammation (r = 0.75, P < 0.001) and histologic inflammation (r = 0.85, P < 0.001). Of the 14 children undergoing 99 Tc scanning, 10 had Crohn disease, 3 had ulcerative colitis, and 1 had allergic colitis. Median fecal calprotectin was 9.1 mg/L (0.3–141.7 mg/L), and this correlated closely with the 99 Tc scanning score (r = 0.80, P = 0.001).
Conclusion: Fecal calprotectin correlates closely with the best invasive measures of colonic and small bowel inflammation in childhood inflammatory bowel disease. As a sensitive objective measure of bowel inflammation that is risk-free and noninvasive, fecal calprotectin lends itself particularly to the monitoring of and assessment of therapeutic interventions in children with inflammatory bowel disease.
*Department of Child Health, University of Aberdeen, Foresterhill, †Royal Aberdeen Children's Hospital, Cornhill Road; ‡Department of Pathology, University of Aberdeen, Foresterhill; and §Department of Radiology, Aberdeen Royal Infirmary, Foresterhill, Aberdeen, United Kingdom
Received April 10, 2000; accepted January 25, 2001.
Financial support was provided by the Sanofi Winthrop Foundation, Surrey, UK.
Address correspondence and reprint requests to Dr. Barbara Golden, Senior Lecturer, Department of Child Health, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, U.K. (e-mail: b.e.golden@abdn. ac.uk).
This article accompanies an editorial. Please see Bjarnason I, Sherwood R. Fecal calprotectin: a significant step in the noninvasive assessment of intestinal inflammation. J Pediatr Gastroenterol Nutr 2001;33:11–3.