Els van de Vijver

31 Table 4 . Scenario analysis Referral based on: Patients subjected to ileocolonoscopy (n) IBD-negative ileocolonoscopy (n) Proportion with IBDnegative ileocolonoscopy “Clinical eye” of the paediatrician 68 26 38% Faecal calprotectin > 50 μg/g 62 20 32% Faecal calprotectin > 50 ug/g (in absence of gastrointestinal infection) 54 12 22% If the decision for referral were to be solely based on the faecal calprotectin result, 32% of the children subjected to ileocolonoscopy would have had a negative result. Basing referral on a positive faecal calprotectin result in the absence of gastrointestinal infection would have resulted in 22% negative ileocolonoscopies, and no missed IBD cases. The reduction of negative endoscopies is significant (p= 0.001). DISCUSSION Implications of key findings To our knowledge, this is the first phase III study that evaluates the usefulness of faecal calprotectin in routine paediatric practice. The analytical eye of the paediatrician selected 68 children and teenagers for endoscopy to confirm IBD, of which 26 (38%) had a negative result. A referral based on a faecal calprotectin level above 50 μg/g without excluding a gastrointestinal infection would wrongly select 20 out of 62 patients (32%). When patients with proven gastrointestinal infections are excluded beforehand the number of IBD-negative endoscopies would be significantly reduced to 22% (12 out of 54 suspected patients) without missing one case of IBD. Ruling out IBD without referral for endoscopy