Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Pharmacol Ther. Feb 6, 2016; 7(1): 126-132
Published online Feb 6, 2016. doi: 10.4292/wjgpt.v7.i1.126
Helicobacter pylori and its reservoirs: A correlation with the gastric infection
Spencer Luiz Marques Payão, Lucas Trevizani Rasmussen
Spencer Luiz Marques Payão, Laboratório de Genética, Hemocentro, Marília Medical School, FAMEMA, São Paulo, CEP 17519-050, Brazil
Spencer Luiz Marques Payão, Lucas Trevizani Rasmussen, Department of Graduate-Level Research Sacred Heart University, Universidade do Sagrado Coração, Bauru, SP 17011-160, Brazil
Author contributions: Payão SLM and Rasmussen LT contributed equally to this work.
Supported by São Paulo Research Foundation (FAPESP), Sacred Heart University of Bauru Marília School of Medicine, No. 2012/18333-3.
Conflict-of-interest statement: The authors declare no conflict of interest.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Correspondence to: Spencer Luiz Marques Payão, Professor, Laboratório de Genética, Hemocentro, Marília Medical School, FAMEMA, Rua Lourival Freire, 240, Bairro Fragata, Marília, São Paulo, CEP 17519-050, Brazil.
Telephone: +55-14-34021856 Fax: +55-14-34330148
Received: April 29, 2015
Peer-review started: April 30, 2015
First decision: July 25, 2015
Revised: October 16, 2015
Accepted: November 10, 2015
Article in press: November 11, 2015
Published online: February 6, 2016

Helicobacter pylori (H. pylori) has long been found to cause gastric diseases such as gastritis, gastric ulcers and gastric cancer. The transmission medium of this bacterium has yet to be determined, though several studies have speculated that the oral cavity is a reservoir for H. pylori. Others have also reported that the oral cavity may be a source of both transmission and gastric reinfection; however, such results are controversial. We reviewed the literature and selected studies that report an association among H. pylori detections in the oral cavity (dental plaque, saliva, tongue, tonsil tissue, root canals, oral mucosa) in humans and in animals, as well as in the human stomach. The oral cavity may be considered the main reservoir for H. pylori. There are a correlations between H. pylori infection in the oral cavity and periodontal disease, oral tissue inflammation, H. pylori transmission, and gastric reinfection. We believe that the mouth is a reservoir and that it plays a crucial role in both H. pylori transmission and gastric infection.

Keywords: Helicobacter pylori, Reservoirs, Oral cavity, Infection, Gastric disease

Core tip: This review focuses on some aspects of infection and reinfection by Helicobacter pylori (H. pylori), particularly in the possible reservoirs of this bacterium. It also explores the association between gastric infection and these reservoirs. In addition, this review highlights possible reservoirs in animals and some routes of infection, and it considers the techniques used to diagnose this bacterium in different environments. The difficulty in accessing bacteria in reservoirs is a problem for H. pylori eradication in particular, and new discoveries in this field will contribute to the understanding of H. pylori infection mechanisms.