In clinical paediatric practice faecal calprotectin, a protein derived from white blood cells, is a reliable, non-invasive and easy-to-perform marker, with a high positive predictive power to identify intestinal inflammation. It is very useful for the follow-up of IBD and its main indications are the differential diagnosis between functional bowel disorders and inflammatory diseases. Intestinal bleeding lesions (determining chronic occult bleeding and/or intermittent bleeding) may be due to a high calprotectin level in asymptomatic patients, and among them the intestinal polyps are the most frequent cause. The article reports the case of an 8-year-old male with occasional increase in faecal calprotectin and the feedback to the colonoscopy of a pedunculated single polyp.