618 STUDY ON THE RELATIONSHIP BETWEEN GASTROESOPHAGEAL REFLUX SYMPTOMS AND ESOPHAGEAL MICROBIOTA

Abstract

Abstract The occurrence of gastroesophageal reflux symptoms is related to the changes of esophageal mucosal sensitivity and esophageal motility. Studies have found that changes in gut microbiota can cause lower digestive tract symptoms by changing intestinal sensitivity and intestinal motility. The current study aimed to explore whether changes of esophageal microbiota can cause gastroesophageal reflux symptoms by altering esophageal sensitivity and esophageal motility. Methods Patients who were admitted to our hospital due to heartburn and reflux symptoms were prospectively included. Ten healthy volunteers and 10 patients with duodenal ulcer were included as controls. Both patients’ and healthy volunteers’ distal esophagus mucosal tissues and gastric fluid were collected under endoscopy for extraction of bacterial DNA. Patients and volunteers were divided into different groups according to disease situations, esophageal motility status, proton pump inhibitor (PPI) treatment efficacy. The α-diversity, β-diversity and specific composition of the microbiota among different groups were compared. Results A total of 12 patients with gastroesophageal reflux disease (G), 16 patients with functional esophageal disorder (F), 10 healthy volunteers (H), and 10 duodenal ulcer patients (D) were included. Esophageal mucosal microbiota analysis revealed that the microbiota composition was similar in patients with gastroesophageal reflux disease and functional esophageal disorders, which significantly different from that in healthy volunteers and patients with duodenal ulcers. Both gastroesophageal reflux disease patients and functional esophageal disorder patients had higher proportion of Pseudomonas than healthy controls and duodenal ulcer patients (G vs. F vs. H vs. D = 25.5% vs. 41.9% vs. 0.2% vs. 1.2%；P = 0.041). Conclusion The microbiota composition of patients with gastroesophageal reflux disease and patients with functional esophageal disorder were similar and were both significantly different from that of healthy volunteers and patients with duodenal ulcer. The increased proportion of Gram-negative bacteria such as Pseudomonas may play an important role in the occurrence of gastroesophageal reflux symptoms.