{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T23:31:09Z","timestamp":1783121469726,"version":"3.54.6"},"reference-count":42,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2022,4,19]],"date-time":"2022-04-19T00:00:00Z","timestamp":1650326400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell. Infect. Microbiol."],"abstract":"<jats:p>In recent years, the role of gastric and duodenal microbiota has acquired increasing importance in the homeostasis of the host, although, to date, most evidence concern the faecal microbiota. Indeed, the gastric, and duodenal microbiota are challenging to study, due to gastric acid, bile, digestive enzymes, and rapid transit time. Specifically, the gastric acid environment may influence their bacterial composition since the acid barrier protects against orally ingested microorganisms and leads to their inactivation before reaching the intestine. The aim of this study was to assess a correlation between intragastric pH and gastric as well as intestinal microbiota of patients with histologic gastric alterations. pH was measured in the gastric juice and the bacterial composition in gastric and duodenal biopsies and faecal samples, was investigated <jats:italic>via<\/jats:italic> 16s rRNA gene sequencing. The main result is the direct correlation of duodenal microbiota biodiversity, <jats:italic>via<\/jats:italic> alpha diversity measures, with intragastric pH values. In particular, patients with hypochlorhydria showed increased duodenal microbiota biodiversity, higher intragastric pH values being prevalent in patients with chronic atrophic gastritis. Lastly, the latter was also strongly associated to the presence of oral bacteria, like <jats:italic>Rothia mucilaginosa, Streptococcus salivarius<\/jats:italic> and <jats:italic>Granulicatella adiacens<\/jats:italic>, in the duodenal microbiota. In conclusions, our results suggest a low-acid gastric environment as a contributive factor for duodenal dysbiosis, potentially leading to the development of pathological conditions of the gastrointestinal tract.<\/jats:p>","DOI":"10.3389\/fcimb.2022.854904","type":"journal-article","created":{"date-parts":[[2022,4,19]],"date-time":"2022-04-19T05:42:00Z","timestamp":1650346920000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":24,"title":["The Potential Role of Hypochlorhydria in the Development of Duodenal Dysbiosis: A Preliminary Report"],"prefix":"10.3389","volume":"12","author":[{"given":"Simone","family":"Filardo","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giulia","family":"Scalese","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Camilla","family":"Virili","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefano","family":"Pontone","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marisa","family":"Di Pietro","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonio","family":"Covelli","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giorgio","family":"Bedetti","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paride","family":"Marinelli","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giovanni","family":"Bruno","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ilaria","family":"Stramazzo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marco","family":"Centanni","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rosa","family":"Sessa","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carola","family":"Severi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2022,4,19]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0002836","article-title":"Comparative Analysis of Human Gut Microbiota by Barcoded Pyrosequencing","volume":"3","author":"Andersson","year":"2008","journal-title":"PloS One"},{"key":"B2","doi-asserted-by":"publisher","first-page":"90","DOI":"10.1186\/s40168-018-0470-z","article-title":"Optimizing Taxonomic Classification of Marker-Gene Amplicon Sequences With QIIME 2\u2019s Q2-Feature-Classifier Plugin","volume":"6","author":"Bokulich","year":"2018","journal-title":"Microbiome"},{"key":"B3","doi-asserted-by":"publisher","first-page":"852","DOI":"10.1038\/s41587-019-0209-9","article-title":"Reproducible, Interactive, Scalable and Extensible Microbiome Data Science Using QIIME 2","volume":"37","author":"Bolyen","year":"2019","journal-title":"Nat. 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