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Specific immunoglobulins: role in the diagnosis of allergies and infectious diseases
What are specific immunoglobulins?
Immunoglobulins are proteins produced by B lymphocytes and play a key role in protecting the body against viruses, bacteria, fungi, and allergens. They act like antibodies, recognizing foreign agents and neutralizing them.
Specific immunoglobulins are special antibodies that the body produces in response to a specific pathogen or substance. Their determination in the blood helps to diagnose infectious diseases, assess the immune response after vaccination, and detect allergic reactions.
“Immunoglobulins are not just markers of diseases, but powerful diagnostic tools that help doctors determine what the human immune system is reacting to,” explains immunologist Andriy Hrytsenko.
Classes of specific immunoglobulins and their significance
Different classes of immunoglobulins perform distinct functions in the immune response.
| Immunoglobulin type | Functions | What determines |
|---|---|---|
| IgA | Protects mucous membranes (respiratory tract, gastrointestinal tract) from viruses and bacteria | Infectious diseases, chronic inflammatory processes |
| IgG | Responsible for long-lasting immunity after infections or vaccinations | Diagnosis of viral and bacterial infections, vaccination effectiveness |
| IgM | First line of defense against acute infections | Acute phases of infectious diseases |
| IgE | Responsible for allergic reactions, activates histamine | Detection of allergic diseases, bronchial asthma |
| IgD | Little studied, participates in triggering the immune response | Immunodeficiency research |
“If a patient has an elevated level of IgE, this almost always indicates the presence of an allergic reaction, especially if the symptoms are chronic,” notes allergist Olena Savchuk.
The role of specific immunoglobulins in the diagnosis of allergies
Immunoglobulin E (IgE) is the main indicator of allergic reactions. Its increase indicates hypersensitivity to certain substances.
The process of an allergic reaction includes several stages:
- Upon first contact with an allergen, the body produces specific IgE, which binds to immune system cells.
- Upon re-exposure, the allergen binds to these antibodies, causing the release of histamine.
- This causes allergy symptoms: rash, itching, swelling, shortness of breath, or even anaphylaxis.
“Diagnosis of allergies based on the level of specific IgE allows not only to confirm the body's reaction, but also to determine which allergens it occurs to,” says allergist Viktoriya Romanenko.
Specific immunoglobulin tests for infectious diseases
Specific IgG and IgM tests are used to identify the stage of the infectious process.
- IgM appear first during acute infection.
- IgG indicate the formation of immunity after a previous disease or vaccination.
“For example, if a patient has a high level of IgG to the measles virus, this means that he has either had the disease or has immunity after vaccination,” explains infectious disease specialist Maksym Litovchenko.
When is a test for specific immunoglobulins prescribed?
The study of specific immunoglobulins is indicated in the following cases:
- suspected allergy (food, pollen, medication)
- diagnostics of infectious diseases (viral and bacterial)
- checking the effectiveness of vaccination
- assessment of immune system function
- diagnostics of autoimmune processes
“Immunoglobulin testing is especially useful in complex or chronic diseases, when it is important to determine how active the immune response is,” adds immunologist Maryna Kovalchuk.
How to prepare for an analysis for specific immunoglobulins
To obtain accurate results, it is important to follow certain rules when preparing for the test:
- the analysis is given on an empty stomach
- avoid physical exertion and stress for 24 hours
- Do not consume fatty foods or alcohol for 12 hours.
- Before testing for IgE, you should refrain from taking antihistamines.
“Violation of the preparation regimen can lead to errors in the analysis results, which can affect the accuracy of the diagnosis,” notes laboratory assistant Oleksandr Demchenko.
Specific immunoglobulins are an important indicator of the immune response, helping not only to diagnose diseases, but also to determine the degree of immune protection. Determining their level allows doctors to timely detect allergic reactions, viral and bacterial infections, as well as assess the effectiveness of vaccination.
