Fecal calprotectin: a quantitative marker of colonic inflammation in children with inflammatory bowel disease.

OBJECTIVES: The protein calprotectin (S100 A8/A9) is present in neutrophils, monocytes, and macrophages. Colorectal inflammation can be detected by increased excretion of fecal calprotectin (FC). The aim of this study was to evaluate FC as a quantitative marker of inflammatory activity in children with inflammatory bowel disease (IBD). PATIENTS AND METHODS: Thirty-nine children with IBD delivered a fecal spot sample and underwent colonoscopy. The samples were examined with an enzyme-linked immunosorbent assay for FC (Calprest, Eurospital, Trieste, Italy). The concentrations were correlated to macroscopic and microscopic assessments of extent and severity of inflammation in 8 colonic segments for each patient. RESULTS: FC correlated significantly to the macroscopic extent (Spearman rho = 0.61) and the severity (Spearman rho = 0.52) of colonic inflammation and to a macroscopic, combined extent and severity score (Spearman rho = 0.65). Significant correlations also were found to the microscopic extent (Spearman rho = 0.71) and severity (Spearman rho = 0.72) of colonic inflammation and to a microscopic, combined extent and severity score (Spearman rho = 0.75). The median FC was 392 mug/g (95% confidence interval [CI], 278-440) in children with clinical IBD symptoms (n = 23) and 32.9 mug/g (95% CI, 9.4-237) in asymptomatic IBD patients (n = 16). Of the asymptomatic children, 56% had a complete microscopic mucosal healing, and their median FC was 9.9 mug/g (95% CI, 5.9-41.9). CONCLUSIONS: FC can be used as a surrogate marker for estimation of colonic inflammation in pediatric IBD. Normalized FC concentration seems to indicate complete mucosal healing. FC is simple to obtain and analyze; this should facilitate objective assessment and monitoring of IBD activity.

Colorectal inflammation is well predicted by fecal calprotectin in children with gastrointestinal symptoms.

OBJECTIVES: The protein calprotectin is mainly derived from neutrophils. Increased fecal excretion of calprotectin has been reported in inflammatory bowel disease. The recommended cut-off level in adults (<50 microg/g feces) seems to be applicable in children aged 4 to 17 years. The aim of this study was to evaluate the use of fecal calprotectin to detect colorectal inflammation in children with gastrointestinal symptoms. METHODS: We obtained stool samples on thirty-six children with gastrointestinal symptoms and suspected inflammation of the colon before they underwent colonoscopy. The samples were examined with an improved fecal calprotectin enzyme-linked immunosorbent assay method (Calprest, Eurospital). The results were correlated with the histopathologic findings in the colon. RESULTS: In children with colorectal inflammation (n = 22) the median fecal calprotectin concentration was 349 microg/g (range, 15.4-1860 microg/g). The most common diagnosis in this group was inflammatory bowel disease. Median fecal calprotectin was 16.5 microg/g (range, 5.0-65 microg/g) in children with no inflammation (n = 14). When <50 microg/g was used as upper reference limit the fecal calprotectin test had a sensitivity of 95%, specificity 93%, positive predictive value 95% and negative predictive value 93% to detect colorectal inflammation. CONCLUSIONS: The improved fecal calprotectin enzyme-linked immunosorbent assay is a simple test with potential use in children. Increased fecal calprotectin strongly predicted the presence of colorectal inflammation in children with gastrointestinal symptoms. Fecal calprotectin can be used to select patients who should undergo diagnostic colonoscopy for investigation of colorectal inflammation, including inflammatory bowel disease.

Fecal calprotectin levels in healthy children studied with an improved assay.

BACKGROUND: Calprotectin is a protein abundant in neutrophils. Fecal calprotectin can be used as a marker of gastrointestinal inflammation, and an improved assay has recently been developed. The aim of this study was to establish reference values for fecal calprotectin in healthy children aged between 4 and 17 years. METHODS: Fecal samples were obtained from 117 healthy children classified into four age groups: 4 to 6 years, 7 to 10 years, 11 to 14 years, and 15 to 17 years. A health questionnaire was used to ensure that these children fulfilled the inclusion criterion and did not have intercurrent disease, nasal or menstrual bleeding, or nonsteroidal anti-inflammatory drug medication before the sampling period. Calprotectin was analyzed using a quantitative enzyme-linked immunosorbent assay (Calprest, Eurospital SpA, Trieste, Italy). Children with fecal calprotectin values >50 microg/g were asked to deliver an additional sample. RESULTS: The overall median fecal calprotectin concentration was 13.6 microg/g (95% confidence interval, 9.9-19.5 microg/g) in the 117 children. In the different age groups, 4 to 6 years, 7 to 10 years, 11 to 14 years, and 15 to 17 years, the median calprotectin concentrations were 28.2, 13.5, 9.9, and 14.6 microg/g, respectively. Of these children, 104 (89%) had a concentration <50 microg/g. The remaining 13 children with a calprotectin concentration >50 microg/g delivered one additional fecal sample. All showed a lower concentration in the second sample except for one teenager who later proved to have proctitis. CONCLUSIONS: The suggested cutoff level for adults (<50 microg/g) can be used for children aged from 4 to 17 years regardless of sex. A fecal calprotectin concentration >50 microg/g warrants follow-up.