Gastric and Duodenal Microbiota in Dyspeptic Subjects

Completed

• Conditions: Microbial Colonization; Gastritis
• Interventions: Genetic: 16S rRNA pyrosequencing analysis

• Registration Number: NCT02542579
• Lead Sponsor: Konkuk University Medical Center

Brief Summary

The composition of gastric microbiota is determined by the status of Helicobacter pylori infection. In subjects who have never been infected by H. pylori, gastric microbiota includes various bacteria, creating ideal microbial diversity. This ideal microbial diversity is destroyed by H. pylori infection at low intragastric pH. Since it is difficult for most bacteria to proliferate within an acidic stomach, relative H. pylori abundance gives rise to microbial dysbiosis. Conversely, unideal microbial diversity is often observed in infected individuals with impaired gastric secretory ability at hypochlorhydric condition. Bacteria producing carcinogenic N-nitrosamine compounds are often detected in individuals with past or chronic H. pylori infection at high intragastric pH. Nonetheless, microbial imbalance that occurs in the earlier phase before gastric carcinognenesis is uncertain.

Detailed Description

Dominant colonization of a specific microbiota leading to dysbiosis may lead to inflammation of the mucosa. We hypothesized that the degree of inflammation depend on the composition of microbiota. This study was aimed to define gastric and duodenal microbiota leading to abnormal histopathology. We further tried to elucidate whether the composition of duodenal microbiota is altered by gastric microbiota.

Among the dyspeptic subjects who visited for upper gastrointestinal (UGI) endoscopy, subjects with drug intake (antibiotics, PPIs, laxatives, antidepressants, statins, metformin) within 3 months will be excluded. Three biopsies will performed at the greater curvature side of the mid-antrum, greater curvature side of the mid-body, and at the duodenum, respectively. Next generation sequencing analysis will be performed for 16S rRNA variable regions using the biopsied samples.

Primary study endpoint is 16S rRNA sequencing findings of gastric and duodenal microbiota.

Secondary endpoints are microbiota linked with higher degrees of inflammation, activity, atrophy and intestinal metaplasia based on the updated Sydney classification. Furthermore, correlation between the microbiota and endoscopy finding will be analyzed.

Study Timeline

• Study First Submitted: 2015-08-23
• Study First Submitted QC: 2015-09-03
• Study First Posted: 2015-09-07
• Study Start: 2016-06
• Primary Completion: 2018-03
• Status Verified: 2018-08
• Study Completion: 2018-08
• Last Update Submitted: 2018-08-05
• Last Update Posted: 2018-08-07

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 98

Inclusion Criteria

• Dyspeptic subjects who visited for evaluation including upper gastrointestinal endoscopy and biopsies
• Age >20 years old

Exclusion Criteria

• Underlying disease(s) that requires managements
• Recent intake of drug(s)
• History of gastrectomy

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Subjects for pyrosequencing analysis	16S rRNA pyrosequencing analysis	Dyspeptic subjects who visited for evaluation and agreed on 16S rRNA pyrosequencing analysis

Primary Outcome Measures

Name	Time	Method
Next generation sequencing analysis for microbiota	up to 6 months	16S rRNA pyrosequencing analysis findings of the gastric and duodenal biopsies

Secondary Outcome Measures

Name	Time	Method
Updated Sydney classification	up to 6 months	0=none, 1=mild, 2= moderate, 3=marked infiltration
Gastrointestinal symptom and food intake score	up to 6 months	Scoring system published in Neurogastroenterol Motil 2016;28:1401-1408
Gastrointestinal endoscopy finding	up to 6 months	Upper gastrointestinal endoscopy findings

Trial Locations

Locations (1)

Konkuk University Medical Center; 🇰🇷 Seoul, Korea, Republic of