Contents
What is Helicobacter pylori?
Helicobacter pylori (formerly Campilobacter pylori) is a gram-negative, twisted, S-shaped bacterium. One of the main characteristics of H. pylory is its ability to produce large amounts of urease.
This microorganism exists mainly under the layer of gastric mucus, where it is protected from the acidic environment created in the stomach. H.pylory plays an important role in the pathogenesis of gastritis and other diseases of the digestive system. H. pylory has been found in approximately 50% of patients undergoing gastroendoscopic examinations – and in 95-100% of cases of type B gastritis and in 90-95% of cases of duodenal ulcers.
How is Helicobacter pylori detected?
H. pylory is identified by invasive and non-invasive methods.
Invasive method – gastric biopsy; the biopsy is either tested for the presence of urease (rapid option) or used as material for culturing bacteria.
Detection of antibodies to Helicobacter pylori (Helicobacter pylori) by blood test
The newest non-invasive method for identifying H. pylory is the serological detection of specific antibodies to H. pylory. It is now recognized that there is a close relationship between the formation of H. pylory colonies on the mucous membrane and the presence of specific antibodies in the blood. A correlation has also been established between antibody concentrations and the severity of H. pylory infection.
Detection of specific antibodies to H. pylory by ELISA is a sensitive and specific test. This is the only test that can diagnose H. pylori infection associated with gastritis without gastroduodenoscopy.
In 90-95% of patients with histologically confirmed H.pylory infection who underwent gastroduodenoscopy, significantly higher levels of specific IgG were observed than in individuals with a histologically confirmed diagnosis of banal gastritis. The same results were obtained when examining children.
A non-invasive method such as a serological test for H. pylory should be preferred when conducting screening studies of patients complaining of nonspecific abdominal pain.
Levels of antibodies to H. pylory in serum are significantly reduced after therapy with drugs against this microorganism in adults and children.
Being reliable, non-invasive and easy to perform, the serological test is a valid diagnostic tool for:
- examination of patients with dyspepsia (adults and children) before endoscopy
- monitoring the effectiveness of drug therapy
- assessing possible reinfection with H. pylory
An increased content of immunoglobulins indicates the following:
- IgM – early stage of H.pylory infection, primary or repeated infection.
- IgG – infection in the active stage, the titer correlates with the severity of the inflammatory process.
- IgA is a chronic stage of infection, a recurrent form.