PPIs are the first-line therapy in functional dyspepsia (FD) but frequently (over-)prescribed with potential adverse events, especially in the long term. As C. difficile and CAP are important causes of morbidity, mortality and healthcare costs, it is important to study the underlying mechanisms of PPI-induced dysbiosis.~In this prospective interventional study, study procedures will be performed at inclusion (1), after a baseline period of 4 weeks (2) and after treatment with Pantoprazole (Pantomed®) 40mg once daily during 4 weeks (3) in healthy volunteers and FD patients. In addition, study procedures will be performed at inclusion (1) and after PPI-withdrawal for 8 weeks in refractory FD patients.~The investigators aim to assess alterations of the duodenal (mucosa-associated and luminal) microbiome with PPI therapy and to correlate changes in the duodenal microbiota with oral and fecal microbiota, bile acids, intestinal permeability and histology and biochemical variables.~The results from this study will help to unravel the onset and extent of dysbiosis and provide additional arguments not to prescribe or continue PPI without clear clinical indications, especially in cases where alternative regimens may be available or the benefits of PPI are uncertain.
Prospective interventional study of the effect of PPI on the duodenal microbiome in healthy volunteers and functional dyspepsia patients