What is Helicobacter pylori?

The bacterium Helicobacter pylori is perhaps one of the most important discoveries in the modern history of medicine.
This bacterium (Figs 2 and 3) is a motile pathogen, 2.5-3 µm long and 0.5-1 µm in diameter, slightly curved or spirally twisted in the arch, with 1-7 whips on the head.

Electron micrographs of Helicobacter pylori Electron micrographs of Helicobacter pylori

Electron micrographs of Helicobacter pylori

Helicobacter pylori can only multiply on the mucous membrane of the human stomach, but in its inactive form it can survive for years in stagnant water, on the ground, and in some animals (e.g. monkeys, cats, and more recently dogs and pigs).

Its importance is due to its pathogenic role in the development of gastric ulcers, duodenal ulcers, gastric cancer and MALT lymphoma (a mucosa-associated lymphoid tissue tumour), and its eradication in these diseases is therefore absolutely justified.

One of the most widespread infections: it is present in 50% of humanity. Infection occurs in infancy and childhood. In Hungary, 40-50% of 20-30 year olds and 65-70% of 50-60 year olds carry the bacterium.

The pathogen has several virulence factors (factors that promote survival and reproduction). It adheres to the mucosa by means of adhesion factors. Its whiskers help it to move. Its production of protease and urease helps it to pass through the mucosa, and the latter also has a cell-damaging effect. By producing phospholipase A and C, it makes the mucosa hydrophilic, which also helps it to survive, and this also has a cell-damaging effect. The function of the vacA and cagA genes is also cytotoxic (cell damaging), important in mediating the pathogenic role of the bacterium. Inflammation-promoting substances (cytokines), hormone production-enhancing (gastrin level-enhancing) effects also help bacterial survival, as does the promotion of nitric oxide production, which affects mucosal circulation. These show that as a pathogen, it can cause damage to the human body through very complex systems.

In our article above we quoted our medical director, Dr.Alajos Takáts: Patient education book on ulcer disease (Springer Publishers, 1998)