If a child presents with matching symptoms suggestive of IBD (so-called “red flag” symptoms) and has additionally one or more abnormal blood tests (anaemia, raised platelets/CRP/ESR/liver enzymes, low albumin), the priority should be to have the child referred promptly to a paediatric gastroenterologist, who will use the FCP result to make a decision about specialist investigations. The gene discussed is CRP; the disease is inflammatory bowel disease.