Helicobacter Pylori: description of infection, methods of diagnosis and therapy, consequences of infection

Almost four decades have passed since the Australian doctors R. Warren and B. Marshall isolated curved microorganisms from biopsies of the gastric mucosa of a patient with gastritis. They were originally classified as Gram-negative bacteria of the genus Campylobacter and named Campylobacter pylori.

But further research has demonstrated its differences in the amino acid sequence, the structure of the outer membrane proteins, and antibiotic sensitivity. As a result, the microorganism was assigned to a new genus Helicobacter (helix - a spiral, bacter - a stick), and the bacterium under study was named Helicobacter pylori.

These are small gram-negative non-spore-forming microbes that have a spiral shape or bend like the Latin letter S. Towards the end of the life cycle, Helicobacter transforms into cocci of the first type. The same process occurs under unfavorable environmental conditions (fluctuations in temperature or acidity). As a result, cocci of the second type are formed.

They represent a kind of frozen form of Helicobacter.

Their metabolism stops, their reproductive and enzymatic ability disappears. However, such cocci can enter the environment, and from there - into the body of another person. In addition, cocci of the second type again acquire pathological activity (turn into a spiral and populate the mucous membrane) under favorable conditions for development in the intestine.

The size of Helicobacter ranges from 0.5 - 1.0 microns, length - 2.5 - 3.5 microns. Outside, the cell of the microorganism is covered with a smooth membrane, on one side there are flagella (from 1 to 6 pieces). These organelles are necessary for the movement of the microorganism "in search of" the optimal vital activity of the pH level and grouping for the early "settlement" of the mucous membrane digestive tract.

For the vital activity of a microorganism, the optimum temperature is + 37 ° C, the pH level is 4.0 - 6.0, although according to the available data the microbe survives even at a much lower pH. In the course of evolution, Helicobacter "learned" to adapt and maintain functional activity even under unfavorable conditions for them. Thus, bacteria produce many enzymes (protease, phospholipase, hemolysin, alkaline phosphatase, etc.) and cytotoxins. In addition, Helicobacters produce a specific protein that reduces the production of hydrochloric acid.

In the end 1980s years, the European group for the study of infection caused by Helicobacter Pylori was formed. Scientists are especially concerned about the possible connection of this bacterium with stomach cancer. Since then, conferences have been constantly held, conciliatory groups have been working to develop a unified tactics for treating the disease. This significantly reduces the risk of microorganism resistance formation.

The infection develops very slowly, the pathogen can remain in the mucous membrane of the digestive tract throughout a person's life. As a rule, Helicobacter fully adapts to the immune system, but in some cases it is possible the release of a variety of cytotoxins that provoke cell dysfunction and inflammatory process.

Helicobacter infection is possible in several ways. For subsequent development, it is necessary that the bacterium does not enter the bloodstream, but on the surface of the mucous membrane of the digestive tract. Infection is likely when:

• carrying out medical or diagnostic manipulations with insufficiently sterilized instruments;
• the consumption of food or water containing cocci Helicobacter of the second type;
• the use of common toothbrushes, dental floss, toothpicks, dishes, since, according to experts, Helicobacter is also present on the oral mucosa.

The symptomatology of a Helicobacter infection depends on many factors. These are the features of the functioning of the human immune system, the principles of diet, hereditary predisposition. In some cases, the disease is not accompanied by clinical manifestations, but colonization of the gastric mucosa causes the formation of antigen-antibody complexes, which can lead to the development of serious and dangerous complications.

But in most patients, Helicobacter proceeds with certain symptoms. This is:

• nausea;
• vomit;
• heartburn;
• pain in the epigastric region;
• flatulence;
• heartburn;
• bloating;
• belching;
• bad taste and bad breath;
• loss of appetite;
• stool disorders;
• sleep disturbance.

In some cases, the clinical picture of Helicobacter infection is not limited to symptoms from the digestive tract. Dermatoses of various localization are noted, sometimes there is an allergic or pustular rash. The appearance of foci of eczema and psoriasis is also associated with Helicobacter. Often, the immune defense against a variety of viruses, fungi and other bacteria is weakened.

Helicobacter pylori: diagnostic methods, complications after infection

Since the discovery of bacteria, more and more new diagnostic methods have appeared, but none of them can be considered universal. The possibilities of research methods are limited by the age of the patient, the stages of infection, and the intake of certain medications.

All diagnostic methods are divided into direct and indirect. The first group includes:

• bacteriological;
• histological;
• molecular biological (PCR - research feces and blood);
• contrast microscopy;
• immunohistochemical.

Indirect methods are:

• urease test;
• serological diagnostics.

Also, the examinations used to make a diagnosis are invasive and non-invasive. The first ones require the collection of biopsy material for fabrogastroduodenoscopy (FGDS), blood. This is:

• bacteriological and morphological (histological or cytological) methods;
• urease test;
• PCR of biopsies;
• ELISA;
• microscopy.

Non-invasive techniques for detecting Helicobacter are becoming more and more popular, especially for preventive examinations and diagnostics at an early age. These include:

• determination of antibodies to Helicobacter in feces, saliva and urine;
• study by the method of polymerase chain reaction of feces, saliva, dental plaque.

Invasive diagnostic techniques

One of the most informative is bacteriological (cultural) research. Its specificity reaches 100%. The advantage of this technique is the ability to determine and antibiotic resistance of Helicobacter. However, this method also has a number of disadvantages. The results are obtained only after 7-10 days; there are also certain difficulties with the transportation of the biological material under study. In addition, bacteriological diagnostics does not distinguish coccal forms. However, many doctors consider such a test necessary before starting treatment due to the growing resistance of bacteria to antibiotics.

The specificity of the histological technique is up to 97%. A biopsy is taken from the gastric mucosa with the most pronounced hyperemia and inflammatory edema. This method allows you to determine the contamination of the mucous membrane and signs of changes in its structure.

Cytological examination is carried out in the study of biopsy prints obtained as a result of endoscopic examination of the stomach and duodenum. The sensitivity of this technique is low (about 20%), but it allows you to identify the first signs of changes in the structure of cells (metaplasia, neoplasia, etc.).

The rapid urease test is considered the standard for diagnosing Helicobacter infection. It is based on the characteristics of the vital activity of the bacteria. Helicobacter, using urease, breaks down the urea contained in the stomach, with the release of ammonia and carbon dioxide, as a result the pH becomes alkaline, which is fixed using a special indicator. The rate of change in shade indicates the degree of infection. The sensitivity of the urease test is up to 98 - 99%; it is often used for the primary diagnosis of Helicobacter.

Phase contrast microscopy is convenient for high speed, but informative only with a large number of pathogenic microorganisms. Immunohistochemical analysis involves the processing of biopsy material with antibodies that selectively stain Helicobacter. The polymerase chain reaction (PCR) technique allows you to determine Helicobacter not only in a smear or biopsy specimen, but also in non-invasive studies. In addition, such an analysis allows you to accurately identify the bacterial strain.

Non-invasive diagnostic methods

The urease breath test is performed using 13C labeled urea. It is offered to the patient during breakfast. Helicobacter decomposes urea, however, carbon markers 13C are retained in the emitted carbon dioxide. The patient exhales into a special test tube, and its contents are further examined using spectrometers, infrared or laser devices.

However, this technique is not performed in patients with bleeding ulcers, atrophic gastritis, and stomach cancer. The widespread use of this diagnostic method is hindered by its high cost.

The specificity of the determination of Helicobacter pylori in feces by PCR reaches 100%. However, the results of such an analysis are distorted against the background of the therapy, in addition, false negative data are possible in elderly patients.

The ELISA method is considered the most suitable for the diagnosis of Helicobacter. A few weeks after infection in the patient's body, specific antibodies to Helicobacter are produced, which are determined during an enzyme-linked immunosorbent assay. Detection of immunoglobulins is possible in saliva or gastric juice. But they persist for many years, so this technique is not suitable for assessing the effectiveness of therapy.

Particular attention is paid to the early identification of patients with an increased risk of developing stomach cancer. For this, screening is carried out to determine the specific markers of atrophy (pepsinogen of the first and second types, gastrin - 17). However, effective therapy aimed at eradicating bacteria significantly reduces the likelihood of malignant cell degeneration.

Diseases and syndromes associated with Helicobacter

Currently, doctors are confident that infection with Helicobacter pylori is a determining factor for the development of:

• chronic gastritis type B;
• gastroduodenitis;
• stomach ulcer and duodenum;
• stomach cancer;
• gastroesophageal reflux disease.

In addition, experts associate Helicobacter infection with:

• iron deficiency anemia (occurs in 40% of patients);
• platelet purpura (in half of patients);
• lack of cyanocobalamin;
• atopic dermatitis.

In recent years, data have appeared on the connection of Helicobacter pylori with stroke, Parkinson's disease, Alzheimer's disease, and coronary heart disease. However, this information has not been clinically confirmed. In addition, the bacterium affects the bioavailability of a number of drugs, which requires a correction of their dosage.

Helicobacter Pylori bacteria in the stomach: features of therapy and drugs used

Clinical studies have demonstrated the resistance of the bacteria to:

• Vancomycin and other glycopeptidas;
• sulfonamides;
• polymyxins.

Doctors associate the development of Helicobacter resistance with a fairly short residence time of the antibiotic in the stomach. It is not enough to completely eradicate the bacteria, but it increases the risk of resistance to conventional therapies. Therefore, a combination treatment is indicated to eliminate Helicobacter.

Currently, there is evidence of high resistance of Helicobacter to:

• nitroimidazole;
• macrolides;
• fluoroquinnolones;
• rifampicin and its derivatives;
• β-lactam antibiotics;
• tetracyclines;
• nitrofurans.

Doctors are concerned about the constantly progressing resistance of Helicobacter to Metronidazole and macrolides, which are widely used to treat bacterial-induced diseases. However, the mechanism of such resistance is not fully understood, although it is associated with gene mutations. It is believed that this is due to the widespread use of these drugs in gynecology, surgery and therapy of pathologies of the bronchopulmonary system.

Doctors additionally use bismuth salts and proton pump blockers. The use of drugs of this group increases the effectiveness of antibiotic therapy up to 100%.

Basic treatment regimens for Helicobacter pylori

The choice of tactics for treating Helicobacter infection depends on the results of bacteriological research.

If the microorganism "responds" to the use of macrolides, a classic three-component regimen is prescribed with an individual selection of dosage:

• proton pump inhibitors;
• Clarithromycin;
• Amoxicillin or Metronidazole.

With resistance to macrolides, quadrotherapy is recommended using:

• proton pump inhibitors;
• Metronidazole;
• Tetracycline;
• bismuth preparations.

In some European countries, stepwise therapy, which includes the appointment of proton pump inhibitors, shows good results. (PPI) and Amoxicillin for 5 to 7 days, and the use of PPI, Clarithromycin and Tinidazole (can be replaced with Metronidazole) for the same term. In some cases, a combination of PPIs, Clarithromycin, Amoxicillin and Metronidazole is prescribed at the same time.

Brief characteristics of antibiotics

Antibacterial drugs cause irreversible death of Helicobacter. The combination of several drugs reduces the risk of developing resistance and shortens the duration of therapy. Assign:

• Amoxicillin (Ospamox, Flemoxin, Hinkocil);
• Clarithromycin (Bacticap, Clarbact, Klacid, Fromilid).

Much less often, tetracycline is prescribed in the treatment of infection. If you are allergic to penicillin antibiotics, Lomefloxacin (Lofox, Xenaquin) is indicated. An integral component of therapy is drugs from the group of nitroimidazoles. Metronidazole is usually prescribed, but the latest generation medicines Tinidazole, Ornidazole and others are considered more effective.

Bismuth based preparations

Bismuth tripotassium dicitrate is optimal if the bacteria Helicobacter Pylori is found in the gastric mucosa. This substance changes the structure and gradually destroys the cells of the pathogenic flora, weakens the influence of the enzymes secreted by Helicobacter. In addition, bismuth tripotassium dicitrate forms a protective film that protects the mucous membrane from the aggressive effects of gastric juice. It also normalizes the secretion of epithelial cells, reduces the activity of pepsin and pepsinogen. The drugs of this group accelerate the regeneration of the mucous membrane, improve the blood supply to the stomach and duodenum.

Bismuth tripotassium dicitrate is a part of such medicines:

• De-Nol;
• Vicanol Life;
• Escape;
• Ulkavis.

Proton pump inhibitors

After absorption from the small intestine and passage through the liver, the active components of drugs in this group concentrate in the secretory tubules of the gastric mucosa and prevent excessive secretion of saline acid.

Drugs of this type include:

• Omeprazole (Omez, Ultop);
• Controlok (Nolpaza, Ultera);
• Lansoprazole (Lancid, Epicur, Lanzap);
• Beret (Pariet, Ontime);
• Esomeprazole (Nexium, Emesol).

They are widely used to treat stomach ulcers and other pathologies of the digestive tract associated with high acidity. Proton pump inhibitors are also included in all treatment protocols for diseases associated with harmful Helicobacter strains.

Helicobacter infection: unconventional methods of therapy, diet, prevention

In some cases, patients prefer to get rid of the infection with folk remedies. Such recipes are especially effective:

• Pour 100 g of chopped white roots over 3 liters of vodka or moonshine, leave for 2 weeks. Take 10 ml three times a day on an empty stomach.
• Pour in a half-liter jar 50 g of marsh creeper and pour cold boiled water to the top. Insist 18 hours, strain and take a tablespoon 3 times a day.
• Mix a half-liter can of onion juice and the same volume of liquid honey. Drink a teaspoon three times a day before meals, wash down with warm water.

An infection caused by Helicobacter requires an appropriate diet. The following should be excluded from the diet:

• hot spices and sauces;
• alcohol;
• coffee, caffeinated drinks, soda;
• pickles, marinades;
• fatty, fried foods, mayonnaise and other sauces prepared with a lot of oil or animal fats;
• concentrated broths;
• confectionery, baked goods, flour products;
• snacks;
• concentrated juices.

Preference is given to steamed dishes in the oven, lean meats and fish, seasonal vegetables and fruits. From drinks advise rosehip broth, weak green or herbal tea, compotes, fruit drinks. Sugar in the diet is replaced with dried fruits and honey.

In most cases, Helicobacter infection can be avoided by following basic hygiene practices. You should always wash your hands before eating, pay attention to the cleanliness of dishes and cutlery in public areas. food, guests, etc. Helicobacter infection responds well to therapy, especially in the early stages before the onset complications. Therefore, preventive examinations are important.