Els van de Vijver

72 DISCUSSION In this international prospective, multicentre cohort study, we demonstrate that a decision strategy based on symptoms, c-reactive protein, haemoglobin and faecal calprotectin offers physicians an opportunity to reliably screen children and teenagers with abdominal pain and non-bloody diarrhoea for IBD before referring them for endoscopy. This strategy indicates with high reliability which patients are at negligible risk for IBD and therefore should not undergo endoscopy. Prompt and accurate prediction of IBD enables paediatricians to efficiently allocate resources in endoscopy units, by reassuring those with a low risk for IBD, and at the same time prioritize those with a high risk for IBD. The time saved by refraining from unnecessary endoscopies may be better used elsewhere in the health care system, such as for offering gut-directed hypnotherapy to those with functional abdominal pain.(15, 16) Comparison with other studies The outcome – IBD – identified by strategy 4 was assessed in a large group of previously undiagnosed children and teenagers presenting with persistent or recurrent non-bloody diarrhoea and abdominal pain. They represented a spectrum of patients that is commonly seen in general paediatric practice. Previous studies on calprotectin included patients with perianal symptoms or overt rectal bleeding.(3,4,17) These red flag symptoms give sufficient reasons for immediate endoscopic evaluation. Inclusion of these patients causes overestimation of the discriminating power relative to the practical situation, where a test or diagnostic strategy is necessary to distinguish those with functional abdominal pain from those with IBD who lack the red flag symptoms. Study limitations Although the estimated sensitivity of strategy 4 to predict IBD was 100%, the 95% confidence interval suggests that IBD may occasionally be missed. Performing careful physical and laboratory examinations and arranging for follow-up will protect the patient from the sequelae of missing a case. For children and teenagers who are categorized as “low-risk” patients, but whose abdominal pain and non-bloody diarrhoea have not improved after one month, we recommend to repeat the faecal calprotectin test. We did not demonstrate yet that following diagnostic strategy 4 has an impact on actual clinical practice. A randomised controlled trial is necessary to measure the impact of Chapter 4 72