Abstract
Background: Duodenal eosinophilia is postulated to play a key role in the pathogenesis of functional dyspepsia. Our objective was to evaluate the relative strength of the associations, between duodenal eosinophil counts functional dyspepsia, symptomatic erosive gastroesophageal reflux disease (GERD), the presence of co-morbidities and a number of other variables.Methods: Eosinophil counts of archived endoscopic duodenal biopsies of 289 subjects were determined by a pathologist blinded to the clinical data. Duodenal eosinophilia was defined by a count of more than 15 per 5 high power fields. Clinical charts were reviewed by a gastroenterologist blinded to the histology review. Results: The primary diagnosis was functional dyspepsia (undifferentiated by subtypes) in 45, symptomatic erosive GERD in 29, gall stone disease in 17, irritable bowel syndrome in 23 and an alternative or undetermined diagnosis in 175 subjects respectively. On logistic regression analyses, eosinophil counts were associated with symptomatic erosive GERD (OR 1.03, 95% CI 1.00 - 1.05; p=0.035) but not functional dyspepsia. Pre-defined duodenal eosinophilia was associated with symptomatic erosive gastro-oesophageal reflux disease (OR 3.13, 95% CI 1.11 - 8.80; p=0.030), the presence of co-morbidities (OR 2.11, 95% CI 1.16 - 3.84; p=0.014), Chinese (compared to Malay and Indian) ethnicity and lower age but not with either functional dyspepsia, irritable bowel syndrome, gallstone disease, Helicobacter pylori infection or gender. Conclusion: Duodenal eosinophilia was associated with symptomatic erosive GERD, the presence of co-morbidities and Chinese ethnicity but not with undifferentiated functional dyspepsia. Taken in conjunction with other studies, these findings support the hypothesis that subsets of GERD and functional dyspepsia may be part of a disease spectrum characterised by duodenal eosinophilia.