Do different H pylori strains – CagA, VacA and BabA – influence degree of gut damage in infected people?
Most people don’t realize that there are many different strains of H pylori and that these strains affect people in different ways. Certain H pylori strains such as Cag-A are more strongly associated with the development of serious diseases. In fact, it is believed that the Cag-A strains may lead to cancer and heart disease, as I explain in my book H pylori – From Heartburn to Heart Attacks.
A Costa Rican study examined the extent to which different H pylori strains damage the stomach. According to the researchers, Costa Rica is one of the countries with the highest incidence and death rates from stomach cancer.
The aim of this particular study was to determine if different H pylori strains were linked with atrophic gastritis in people with dyspepsia.
In the study, which involved 264 people, H pylori infection was determined by PCR and serology. The presence of three H pylori strains was determined. These were:
73% of the study group was infected with H pylori. 6% presented normal stomach mucosa, 68% presented inflammation but not atrophic gastritis and 26% presented with atrophic gastritis.
The researchers found that people who were infected with the CagA and VacA strains tended to have a greater degree of atrophic gastritis than people who were diagnosed with the BabA strain.
Atrophic gastritis is a known risk factor for stomach cancer. It is a condition in which the stomach lining is severely worn away through chronic inflammation and damage caused by H pylori. The fact that CagA strains in particular, were associated with an increase in atrophic gastritis in this study, is interesting because CagA H pylori strains are associated with increased stomach cancer risk.
In my research I have also found that CagA H pylori bacteria are also associated with the development of heart disease, as well as many of its risk factors.
J. Garita-Cambronero. Association of H. pylori virulence factors with atrophic gastritis in dyspeptic patients from a population at high risk of gastric cancer in Costa Rica. European Helicobacter Study Group. XXIII International Workshop on Helicobacter and Related Bacteria in Chronic Digestive Inflammation and Gastric Cancer. Rotterdam, September 16–18, 2010. P. 370.
Dave Hompes’ Comments
There is no doubt that different H pylori strains have the ability to cause different levels of damage in the body. My biggest concern around this topic is the medical system does not acknowledge the severity of possible outcomes from having H pylori.
H pylori infection causes stomach cancer.
H pylori infection causes – or at least contributes to – heart disease
In other words, H pylori is not just some stupid bacterium that causes a few digestive symptoms and the occasional ulcer. It poses a serious threat to human health.
Unfortunately, different H pylori strains tend not to be identified outside the research setting. A blanket diagnosis of H pylori is given to patients without any knowledge of the possible impact of these different strains.
Because H pylori treatments are only around 70% effective, failure to eradicate certain strains of the bacterium may lead to serious consequences.