Helicobacter pylori Eradication Causes Perturbation of the Human Gut Microbiome in Young Adults

Theresa Wan-Chen Yap, Han-Ming Gan, Yin-Peng Lee, Alex Hwong-Ruey Leow, Ahmad Najib Azmi, Fritz Francois, Guillermo I Perez-Perez, Mun-Fai Loke, Khean-Lee Goh, Jamuna Vadivelu, Theresa Wan-Chen Yap, Han-Ming Gan, Yin-Peng Lee, Alex Hwong-Ruey Leow, Ahmad Najib Azmi, Fritz Francois, Guillermo I Perez-Perez, Mun-Fai Loke, Khean-Lee Goh, Jamuna Vadivelu

Abstract

Background: Accumulating evidence shows that Helicobacter pylori protects against some metabolic and immunological diseases in which the development of these diseases coincide with temporal or permanent dysbiosis. The aim of this study was to assess the effect of H. pylori eradication on the human gut microbiome.

Methods: As part of the currently on-going ESSAY (Eradication Study in Stable Adults/Youths) study, we collected stool samples from 17 H. pylori-positive young adult (18-30 years-old) volunteers. The same cohort was followed up 6, 12 and 18 months-post H. pylori eradication. The impact of H. pylori on the human gut microbiome pre- and post-eradication was investigated using high throughput 16S rRNA gene (V3-V4 region) sequencing using the Illumina Miseq followed by data analysis using Qiime pipeline.

Results: We compared the composition and diversity of bacterial communities in the fecal microbiome of the H. pylori-positive volunteers, before and after H. pylori eradication therapy. The 16S rRNA gene was sequenced at an average of 150,000-170,000 reads/sample. The microbial diversity were similar pre- and post-H. pylori eradication with no significant differences in richness and evenness of bacterial species. Despite that the general profile of the gut microbiome was similar pre- and post-eradication, some changes in the bacterial communities at the phylum and genus levels were notable, particularly the decrease in relative abundance of Bacterioidetes and corresponding increase in Firmicutes after H. pylori eradication. The significant increase of short-chain fatty acids (SCFA)-producing bacteria genera could also be associated with increased risk of metabolic disorders.

Conclusions: Our preliminary stool metagenomics study shows that eradication of H. pylori caused perturbation of the gut microbiome and may indirectly affect the health of human. Clinicians should be aware of the effect of broad spectrum antibiotics used in H. pylori eradication regimen and be cautious in the clinical management of H. pylori infection, particularly in immunocompromised patients.

Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Fig 1. Alpha diversity analysis comparing between…
Fig 1. Alpha diversity analysis comparing between baseline and 6-months post-H.
pylori eradication. Rarefraction curve for A. chao1, B. observed species, C. PD whole tree, and D. the Shannon index generated from alpha diversity analysis.
Fig 2. Alpha diversity analysis comparing between…
Fig 2. Alpha diversity analysis comparing between baseline and 12-months post-H. pylori eradication.
Rarefraction curve for A. chao1, B. observed species, C. PD whole tree, and D. the Shannon index generated from alpha diversity analysis.
Fig 3. Alpha diversity analysis comparing between…
Fig 3. Alpha diversity analysis comparing between baseline and 18-months post-H. pylori eradication.
Rarefraction curve for A. chao1, B. observed species, C. PD whole tree, and D. the Shannon index generated from alpha diversity analysis.
Fig 4. Relative abundance of phyla.
Fig 4. Relative abundance of phyla.
Relative abundance of phyla at A. Baseline, B. 6 months-post eradication, C. 12 months-post eradication, and D. 18 months-post eradication.
Fig 5. Relative abundance of genera.
Fig 5. Relative abundance of genera.
Comparison of the relative abundance of genera between A. Baseline vs. 6 months-post eradication, B. Baseline vs. 12 months-post eradication, and C. Baseline vs. 18 months-post eradication.

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