Pathogenesis and clinical management of Helicobacter pylori gastric infection

World J Gastroenterol. 2019 Oct 7;25(37):5578-5589. doi: 10.3748/wjg.v25.i37.5578.


Helicobacter pylori (H. pylori) is a gram-negative bacterium that infects approximately 4.4 billion individuals worldwide. However, its prevalence varies among different geographic areas, and is influenced by several factors. The infection can be acquired by means of oral-oral or fecal-oral transmission, and the pathogen possesses various mechanisms that improve its capacity of mobility, adherence and manipulation of the gastric microenvironment, making possible the colonization of an organ with a highly acidic lumen. In addition, H. pylori presents a large variety of virulence factors that improve its pathogenicity, of which we highlight cytotoxin associated antigen A, vacuolating cytotoxin, duodenal ulcer promoting gene A protein, outer inflammatory protein and gamma-glutamyl transpeptidase. The host immune system, mainly by means of a Th1-polarized response, also plays a crucial role in the infection course. Although most H. pylori-positive individuals remain asymptomatic, the infection predisposes the development of various clinical conditions as peptic ulcers, gastric adenocarcinomas and mucosa-associated lymphoid tissue lymphomas. Invasive and non-invasive diagnostic methods, each of them with their related advantages and limitations, have been applied in H. pylori detection. Moreover, bacterial resistance to antimicrobial therapy is a major challenge in the treatment of this infection, and new therapy alternatives are being tested to improve H. pylori eradication. Last but not least, the development of effective vaccines against H. pylori infection have been the aim of several research studies.

Keywords: Antibiotics; Helicobacter pylori; Immune response; Vaccines; Virulence factors.

Publication types

  • Review

MeSH terms

  • Antacids / therapeutic use
  • Anti-Bacterial Agents / pharmacology
  • Anti-Bacterial Agents / therapeutic use
  • Bacterial Vaccines / therapeutic use
  • Drug Resistance, Bacterial
  • Drug Therapy, Combination
  • Gastric Mucosa / drug effects
  • Gastric Mucosa / microbiology*
  • Gastric Mucosa / pathology
  • Helicobacter Infections / diagnosis
  • Helicobacter Infections / microbiology
  • Helicobacter Infections / therapy*
  • Helicobacter Infections / transmission
  • Helicobacter pylori / drug effects
  • Helicobacter pylori / immunology
  • Helicobacter pylori / pathogenicity*
  • Humans
  • Hydrogen-Ion Concentration / drug effects
  • Probiotics / administration & dosage
  • Proton Pump Inhibitors / therapeutic use
  • Stomach Diseases / diagnosis
  • Stomach Diseases / microbiology
  • Stomach Diseases / therapy*
  • Treatment Outcome
  • Virulence Factors / metabolism


  • Antacids
  • Anti-Bacterial Agents
  • Bacterial Vaccines
  • Proton Pump Inhibitors
  • Virulence Factors