Stool test for Helicobacter pylori

Currently, Helicobacter pylori is recognized as one of the most frequently diagnosed infections affecting humans. The name of this pathogenic microbe literally translates as "spiral-shaped bacteria living in the pyloric (lower) segment of the stomach." The microorganism is an anaerobic gram-negative motile bacteria that settle among the folds of the gastric mucosa. Among the many ways to diagnose their presence in the digestive tract is a stool test for Helicobacter Pylori. This research procedure is simple, so it is often prescribed to children, the elderly, and seriously ill patients.

Reliability of Helicobacter Pylori Stool Test Results

To determine the presence of Helicobacter pylori, several types of tests are used, including stool or blood tests.

Stool analysis for Helicobacter pylori is a qualitative study, i.e. it indicates the presence or absence of the bacterial agent in the digestive tract, without an exact count. Diagnostics are performed in laboratory and clinical conditions, using the polymerase chain reaction method. The reliability of the results is considered to be quite high – about 95%. Considering this, as well as the ease of implementation, the study is often recommended for most patients with suspected gastritis, stomach ulcers, etc. [ 1 ]

Indications for the procedure a stool test for Helicobacter pylori.

A stool test for Helicobacter pylori can be prescribed to any patient who complains of pain and discomfort in the epigastric region. More precisely, the most common reasons for prescribing the test are:

• discomfort in the upper abdomen after eating;
• regular and unpleasant belching;
• periodically bothersome heartburn;
• difficulty swallowing food;
• increased gas formation, impaired digestion of food;
• regular attacks of nausea, vomiting;
• frequent alternation of periods of diarrhea and constipation;
• loss of appetite, food intolerance, cachexia;
• blood in the stool or vomit.

These signs do not always indicate the presence of Helicobacter pylori in the stool. However, the analysis is a way to help confirm or refute the presence of infection, which will fundamentally affect the treatment of the disease.

Preparation

The accuracy of the stool test result for Helicobacter pylori depends not only on the quality of laboratory diagnostics, but also on how clearly the patient follows the stages of preparation for diagnostics.

Here's how to properly submit a stool sample for Helicobacter:

• Four weeks before the expected test, you should stop taking any antimicrobial drugs;
• three days before, you need to eliminate from your diet so-called “coloring” foods, which include beets, dark grapes, chokeberries, etc.;
• 3-4 days before the examination, you must stop taking laxatives and activated charcoal.

How to collect stool for Helicobacter?

• The stool sample for analysis is separated into a special container, which can be found in a pharmacy or requested directly from the laboratory;
• for adequate diagnostics it will be sufficient if the container is filled to 1/3 or 1/2 of its volume;
• You should not remove feces from the toilet, as it may contain traces of cleaning and detergents.

How to store stool samples for Helicobacter?

It is advisable to take the stool for analysis to the laboratory immediately after collection. If necessary, it can be stored for no more than 10-12 hours in a refrigerator, in a tightly sealed container, in a temperature range from +2 to +8°C. [ 2 ]

Technique a stool test for Helicobacter pylori.

There are several methods to determine the presence of Helicobacter pylori in the digestive tract.

A qualitative analysis helps to find out whether such a bacterium is present in the body at all. The polymerase chain reaction method – PCR of feces for Helicobacter – is performed in laboratory conditions. Specialists point out the high accuracy of diagnostics: more than 90%.

Stool for Helicobacter antigen is submitted for analysis using the immunochromatographic method with monoclonal antibodies. Antigens of the bacteria in the patient's body provoke the development of an immune response: we are talking about the production of antibodies (they are also called immunoglobulins). This study is also qualitative: it can be prescribed, in particular, to those people who have had close contact with patients suffering from gastrointestinal pathologies.

When a patient comes to the doctor, he or she may prescribe several different tests at the same time – for example, a stool test for Helicobacter, a blood test, a study of the stomach contents, etc. This is necessary in order to clearly determine the diagnosis and prescribe the correct treatment measures.

The Helicobacter pylori ELISA is performed within one working day, but in an urgent case the result can be obtained in two hours. The method is based on the principle of thin-layer chromatography and consists of the “antigen-antibody” reaction in the corresponding biomaterial. Diagnostics are carried out using specific test strips, cassettes or panels. [ 3 ]

Normal performance

Helicobacter pylori is a microbe that inhabits the mucous membranes of the stomach: the microorganisms adhere to the villous epithelium and become a provoking factor in the development of 85% of ulcerative lesions of the stomach and duodenum. It is advisable to examine fecal samples in case of relapse of the disease, however, there are no special requirements for the timing of the analysis. Feces of any consistency are suitable for the study.

The analysis results can only be displayed in two variants: bacteria (+) or (-). The device for conducting a stool analysis for Helicobacter pylori is not required. [ 4 ]

Raising and lowering of values

There is nothing complicated in interpreting the results of a stool test for Helicobacter pylori, since most often only two final options are indicated on the laboratory form:

• the result is negative – Helicobacter pylori bacteria were not detected;
• the result is positive – the Helicobacter pylori bacteria is present.

Increase and decrease of values occur if the patient's venous blood is taken for the study. Stool analysis is only a qualitative diagnosis, without counting the probable number of pathogenic microorganisms.

Positive stool test for Helicobacter

There is no need to assume that a positive stool test for Helicobacter directly indicates the presence of pathologies of the stomach and duodenum. It often happens that the carrier of the infection is completely healthy, since he has genetic immunity to the bacteria: this means that the microorganisms are simply not able to linger on the mucous layer of the stomach.

Situations where the presence of Helicobacter is associated with symptoms characteristic of chronic inflammation of the duodenum or stomach ulcers are considered clinically significant.

However, regardless of the severity of the clinical picture, a positive stool test for Helicobacter pylori should be a reason for prescribing eradication (anti-Helicobacter) treatment.