Chronic abdominal pain, fatigue and inflammatory bowel disease in children
This dissertation of Els van de Vijver addresses two particular knowledge gaps out of the many that exist in paediatric inflammatory bowel disease (IBD). Van de Vijver: "First, we evaluated diagnostic strategies to assess whether gastrointestinal complaints are due to IBD, for appropriate triage for endoscopic evaluation. We initially evaluated faecal calprotectin (FC) as an isolated triage test. Even though adding FC results to the decision strategy improved the diagnostic yield compared to the standard diagnostic strategy of that time, still 22% of the patients would have been subjected to an IBD-negative ileocolonoscopy. Subsequently, we evaluated whether another faecal biomarker for mucosal inflammation, calgranulin-C is better than FC in predicting IBD in children and teenagers. We concluded that the diagnostic accuracy of the calgranulin-C test was not superior to the FC test. Evaluating the diagnostic accuracy when patients with red flag symptoms are included may have exaggerated the diagnostic accuracy of FC to diagnose IBD. We therefore set out to determine the optimal test strategy in patients without red flag symptoms and found that triaging with positive symptoms and FC>250 µg/g revealed an AUC of 0.930.Secondly, we quantified and characterized fatigue in IBD. Study of the literature learned that fatigue should be regarded as a multidimensional phenomenon, distinguished by biological, psychobehavioral and functional factors. In a cross sectional cohort study, we found no differences between fatigued or non-fatigued groups in terms of FC, haemoglobin and ferritin concentrations. The quality-of-life score was inversely related to fatigue: the more fatigued, the lower the quality-of-life score."