Helicobacter pylori infection and dyspepsia in primary care: studies on diagnosis and guideline implementation

In this thesis various studies on the management of patients presenting with dyspepsia in primary care are described. Of all patients presenting with dyspepsia, only a minority has organic disease. Roughly 25% of the dyspeptic patients presenting in primary care is referred for endoscopy. At endoscopy, relevant organic disease is found in 30-45% of the patients (5-15% peptic ulcer disease and 25-30% gastro-oesophageal disease). Helicobacter pylori (H pylori) infection is accepted as the most common cause of gastritis, and is aetiologically involved in gastric ulcer, duodenal ulcer and primary gastric B-cell lymphoma. For this reason, the role of H pylori diagnosis and treatment in the management of peptic ulcer disease (PUD) has been a topic of interest in research. Ideally, patients suspected of PUD should be tested for H pylori infection without undergoing endoscopy. H pylori eradication is effective PUD treatment and prevents relapses. Therefore, the diagnostic value of non-invasive H pylori tests (i.e. tests not requiring an endoscopy) in PUD diagnosis should be evaluated. In addition, the additional diagnostic value of H pylori tests in patients at risk for PUD have to be determined. Finally, a guideline based on the established diagnostic value of H pylori testing in dyspeptic patients in primary care needs to be developed and introduced effectively in medical practice. The research questions answered in this thesis are: * To what extent is H pylori diagnosis and treatment currently incorporated in dyspepsia management in primary care in the Netherlands? * What is the value of H pylori testing in addition to history taking in diagnosing peptic ulcer disease in primary care? * What is the optimal non-invasive H pylori test for diagnosis in primary care? * What is the diagnostic performance of a new immunoassay for the detection of H pylori infection in primary care? * Is compliance with a new dyspepsia guideline increased after introduction by an educational or financial stimulus for GPs?