Trends in clinical practice in common pediatric gastro-intestinal disorders

This thesis discusses diagnostic- and therapeutic dilemma’s in daily clinical practice in children with chronic abdominal pain (CAP), with a main focus on celiac disease (CD) and Dientamoeba fragilis (D. fragilis) as potential causes of CAP. CAP is one of the most common clinical conditions amongst children and adolescents globally with a high prevalence in the Western pediatric population. Despite its high prevalence, only a small proportion of CAP is caused by organic disease and approximately 90% of children with CAP fulfill the diagnostic criteria of the functional abdominal pain disorders (FAPD). Identifying this small proportion of children with an organic cause of CAP is of great importance because of the significant implications on both growth and development of these organic causes of CAP. However, it can be puzzling for clinicians and most often leads to the execution of additional diagnostic tests to differentiate between functional and organic causes of CAP. The absence of clear-cut clinical guidelines, and the necessity to exclude organic causes to diagnose FAPD which is incorporated in its diagnostic criteria, potentially often leads to the execution of unnecessary diagnostic tests, potential false- positive or false-negative results, generation of extra financial costs and generation of results of which the clinical relevance can be unclear. Such as, for instance, the role of the flagellate anaerobic parasite D. fragilis in causing gastro-intestinal symptoms in children. What is clear, however, is, that testing for CD in children with CAP is essential because of the relatively high prevalence of the disease in the Western population and its significant consequences regarding treatment. However, over the past decades incidence rates and the clinical spectrum of presenting symptoms of children with CD changed significantly. This has led to shifting paradigms in diagnostic- and therapeutic management of children with CD and D. fragilis.
The aims of this thesis were to evaluate guideline adherence amongst clinicians treating children with CAP and CD, to investigate the current clinical spectrum of pediatric CD, to investigate the clinical relevance of the suggested routine biochemical tests during follow-up suggested by the guidelines, and to evaluate the role of D. fragilis in causing CAP in children.