Helicobacter pylori is a bacterium that is found in the stomach and duodenum mucosa. It is spiral-shaped, which is why it is able to survive in strongly acid environments. After being ingested, the bacteria penetrates in the stomach mucosa and starts secreting ureases. Due to this enzyme, it is able to survive in the acid environment, producing ammonia through the hydrolysis of urea.
There are several Helicobacter pylori strains, with various degrees of virulence. Type I strains induce a gastric inflammatory response and they are more frequently associated to ulcer, gastric cancer and MALT lymphoma (lymphoid tumours associated to the mucosa). The bacteria causes a chronic inflammation of the gastric mucosa in all infected people.
Most people whose digestive tract is contaminated with Helicobacter pylori have no disease signs or symptoms. However, in certain cases, the infection may have the following manifestations:
- Abdominal pain or burn;
- Frequent eructation;
The Helicobacter pylori infection risk factors are related to the living conditions, such as:
- People living in crowded areas. The risk to contract the infection is higher if the respective person lives in a crowded area;
- The lack of a drinking water source. A water source that is not properly treated against bacteria may represent a hot spot;
- Living with an infected person. The bacteria is usually transmitted to people living together with the individual infected with the Helicobacter pylori bacteria.
The infected body produces antibodies that are unable to eradicate the infection, but that can, however, contribute to gastric atrophy.
The following tests are available to identify the presence of the bacteria in the stomach:
- Serum antibody test: it is performed in the venous blood. It is unable to detect reinfection
- Urea breath test: it is performed with radioactive carbon, but it is reserved for research purposes
- Stool antigen test: the most convenient and useful method
- Gastric biopsy: performed through endoscopy. It should be mentioned that endoscopy may induce nausea or bloating. Moreover, it may cause the irritated, sore throat sensation, light hoarseness or the slight inflammation of the pharynx; these symptoms may last for a few days;
The gastric cancer incidence is growing, especially in developed countries, the Helicobacter pylori infection being the most frequently identified risk factor in non-cardia gastric cancer ethiopathogenesis. In Romania, gastric cancer ranks second in terms of incidence amongst digestive cancers, after the colon cancer. H. Pylori eradication is efficient is performed if performed prior to the onset of precancerous lesions (gastric atrophy, intestinal metaplasia).
H. Pylori should also be eradicated in asymptomatic patients if:
- they have 1st degree relatives suffering from gastric cancer;
- they suffer from long-lasting chronic gastritis (with severe atrophy or achlorhydria);
- they have a history of exposure to factors such as: smoking, dust, cement; e.g.: quarry workers.
Cristina Maria Stroi, MD
Internal Medicine Medical Specialist – LaurusMedical