Gastric and Duodenal Microbiota in Dyspeptic Subjects

Composition of Gastric and Duodenal Microbiota in Dyspeptic Subjects

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.

Study Overview

• Status: Completed
• Conditions: Gastritis; Microbial Colonization
• Intervention / Treatment: Genetic: 16S rRNA pyrosequencing analysis

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 Type: Observational
• Enrollment (Actual): 98

Contacts and Locations

Study Locations

• Korea, Republic of
  • Seoul, Korea, Republic of, 05030
    • Konkuk University Medical Center
  • Seoul, Korea, Republic of, 143729
    • Konkuk University Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Dyspeptic subjects for analysis

Description

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 Plan

How is the study designed?

Design Details

• Observational Models: Case-Only
• Time Perspectives: Prospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Subjects for pyrosequencing analysis; Dyspeptic subjects who visited for evaluation and agreed on 16S rRNA pyrosequencing analysis	Genetic: 16S rRNA pyrosequencing analysis; Next generation sequencing analysis will be done for 16S rRNA V1,2 hypervariable regions at Biocore (Seoul, Korea).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Next generation sequencing analysis for microbiota	16S rRNA pyrosequencing analysis findings of the gastric and duodenal biopsies	up to 6 months

Secondary Outcome Measures

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

Collaborators and Investigators

• Sponsor: Konkuk University Medical Center
• Investigators: Principal Investigator: Sun-Young Lee, M.D., Ph.D., Konkuk University

Publications and helpful links

General Publications

• Lee SY, Moon HW, Hur M, Yun YM. Validation of western Helicobacter pylori IgG antibody assays in Korean adults. J Med Microbiol. 2015 May;64(Pt 5):513-518. doi: 10.1099/jmm.0.000050. Epub 2015 Mar 9.
• Lee SP, Lee SY, Kim JH, Sung IK, Park HS, Shim CS, Moon HW. Correlation between Helicobacter pylori infection, IgE hypersensitivity, and allergic disease in Korean adults. Helicobacter. 2015 Feb;20(1):49-55. doi: 10.1111/hel.12173. Epub 2014 Sep 25.
• Lee SY. Future candidates for indications of Helicobacter pylori eradication: do the indications need to be revised? J Gastroenterol Hepatol. 2012 Feb;27(2):200-11. doi: 10.1111/j.1440-1746.2011.06961.x.

Study record dates

Study Major Dates

• Study Start (Actual): June 1, 2016
• Primary Completion (Actual): March 1, 2018
• Study Completion (Actual): August 1, 2018

Study Registration Dates

• First Submitted: August 23, 2015
• First Submitted That Met QC Criteria: September 3, 2015
• First Posted (Estimate): September 7, 2015

Study Record Updates

• Last Update Posted (Actual): August 7, 2018
• Last Update Submitted That Met QC Criteria: August 5, 2018
• Last Verified: August 1, 2018

More Information

Terms related to this study

• Keywords: Helicobacter pylori; Dyspepsia
• Additional Relevant MeSH Terms: Digestive System Diseases; Pathologic Processes; Disease Attributes; Gastrointestinal Diseases; Stomach Diseases; Gastroenteritis; Gastritis; Infections; Communicable Diseases
• Other Study ID Numbers: KUH1010691

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No