Diagnostic value of faecal calprotectin in paediatric gastroenterology clinical practice.

BACKGROUND: Faecal calprotectin (FC) is a new marker of intestinal inflammation. Data on FC in paediatric gastroenterology clinical practice are still scarce. AIMS: To assess FC values in different paediatric gastrointestinal diseases comparing them with those obtained in healthy children. PATIENTS: Two hundred and eighty-one children (age range 13-216 months) consecutively referred for gastrointestinal symptoms. Seventy-six healthy controls (age range 13-209 months). The exclusion criteria in healthy children were the following: any known underlying chronic disease or a history of abdominal pain, diarrhoea, acute respiratory tract infection, intake of non-steroidal anti-inflammatory drugs, gastric acidity inhibitors, antibiotics, drugs influencing gut motility, and menstrual or nasal bleeding in the last 3 weeks.
METHODS: Stool samples stored, prepared and analyzed by an ELISA assay.
RESULTS: In healthy children the median FC value was 28.0 microg/g (15-57 interquartile range) with a 95th percentile value of 95.3 microg/g. An increase in FC concentration was observed in all diseases characterized by gastrointestinal mucosa inflammation, and the active inflammatory bowel disease patients showed the higher FC values. All children affected by functional bowel disorders or by non-inflammatory diseases showed normal values. We calculated an optimized FC cut off value of 102.9266 microg/g (revealed by the receiver operating characteristic curve) to distinguish patients with active organic/inflammatory disorders from healthy subjects and from patients with functional bowel disorders.
CONCLUSIONS: Calprotectin is a sensitive, but not disease specific, marker to easily detect inflammation throughout the whole gastrointestinal tract. It may help in identifying an organic disease characterized by intestinal mucosa inflammation and in the differential diagnosis of functional bowel disorders.