Implications of eosinophilia in the normal duodenal biopsy - an association with allergy and functional dyspepsia.

BACKGROUND Allergy and functional gastrointestinal disorders have been associated with eosinophilia in duodenal mucosa. AIM To assess the prevalence of eosinophilia in duodenal biopsies of patients attending for oesophogastroduodenoscopy and delineate associated clinical conditions. METHODS A total of 155 patients (mean age 55 years, 59% women) with normal duodenal biopsies were randomly selected for audit from histopathology files. Eosinophil counts in five high power fields (HPFs) were assessed. Records were analysed for symptoms, diagnosis and medications; patients were divided into five groups based on upper gastrointestinal (UGI) symptom profiles, including a control group of those without predominant UGI symptoms. The prevalence of duodenal eosinophilia (defined as >22/5HPFs a priori) was calculated. RESULTS In the control group, the mean duodenal eosinophil count was 15/5HPFs; prevalence of duodenal eosinophilia was 22.5%. In postprandial distress syndrome (PDS), both mean eosinophil counts (20.2/5HPF, P < 0.04) and prevalence of duodenal eosinophilia (47.3%, P < 0.04) were significantly higher. Duodenal eosinophilia was significantly associated with allergy (OR 5.04, 95% CI 2.12-11.95, P < 0.001). There was no association with irritable bowel syndrome or medications. CONCLUSIONS Subtle duodenal eosinophilia is relatively common in routine oesophogastroduodenoscopy and previously overlooked; it is associated with allergy and may indicate a hypersensitivity mechanism in some patients with PDS including early satiety.