Clinical trial NCT02542579: Gastric and Duodenal Microbiota in Dyspeptic Subjects
Official title: Composition of Gastric and Duodenal Microbiota in Dyspeptic Subjects
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Microbial Colonization
Gastritis
Keywords: Helicobacter pylori
Dyspepsia
Lead sponsor: Konkuk University Medical Center
Sponsor class: OTHER
First posted: 2015-09-07
Enrollment: 98
Sex: ALL
Minimum age (years): 20
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_ONLY
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Dyspeptic subjects for analysis

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.

Eligibility criteria: 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

Primary outcomes:
measure: Next generation sequencing analysis for microbiota
timeFrame: up to 6 months
Secondary outcomes:
measure: Updated Sydney classification
timeFrame: up to 6 months
measure: Gastrointestinal endoscopy finding
timeFrame: up to 6 months
measure: Gastrointestinal symptom and food intake score
timeFrame: up to 6 months
Other outcomes:
Locations:
city: Seoul
country: Korea, Republic of
facility: Konkuk University Medical Center
city: Seoul
country: Korea, Republic of
facility: Konkuk University Medical Center
Study officials:
affiliation: Konkuk University
name: Sun-Young Lee, M.D., Ph.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: 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.
citation: 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.
citation: 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.